Knowledge · Natural Compounds

Vitamin D

Q: Does Vitamin D help with infections and immune system? What the studies show

We evaluated 19 meta-analyses or systematic reviews, 40 controlled studies and 6 further studies; the controlled studies include 7,232 participants in total. Result of the controlled studies: mostly improved. Strength of evidence under our published rules: high. Sources: [2, 9, 11, 13]

Q: Does Vitamin D help with bones, falls and fractures? What the studies show

We evaluated 6 meta-analyses or systematic reviews, 41 controlled studies and 8 further studies; the controlled studies include 11,754 participants in total. Result of the controlled studies: mixed. Strength of evidence under our published rules: high. Sources: [4, 5, 6, 7]

Q: Does Vitamin D help with blood sugar and metabolism? What the studies show

We evaluated 14 meta-analyses or systematic reviews, 31 controlled studies and 6 further studies; the controlled studies include 46,556 participants in total. Result of the controlled studies: mixed. Strength of evidence under our published rules: high. Sources: [17, 20, 21, 23]

Q: Does Vitamin D help with heart, circulation and blood pressure? What the studies show

We evaluated 11 meta-analyses or systematic reviews, 30 controlled studies and 3 further studies; the controlled studies include 26,146 participants in total. Result of the controlled studies: mostly no difference. Strength of evidence under our published rules: high. Sources: [1, 3, 21, 32]

Q: Does Vitamin D help with mood and depression? What the studies show

We evaluated 5 meta-analyses or systematic reviews and 17 controlled studies; the controlled studies include 4,067 participants in total. Result of the controlled studies: mostly improved. Strength of evidence under our published rules: high. Sources: [12, 32, 51, 74]

Q: Does Vitamin D help with pregnancy and children? What the studies show

We evaluated 5 meta-analyses or systematic reviews, 10 controlled studies and 5 further studies; the controlled studies include 5,476 participants in total. Result of the controlled studies: mixed. Strength of evidence under our published rules: high. Sources: [17, 19, 33, 76]

Q: Which forms of vitamin D were investigated in the studies?

The studies used predominantly oral preparations with cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2), sometimes calcifediol. Some studies tested vitamin D together with calcium, vitamin K2, omega-3 fatty acids, magnesium, zinc or probiotics. The exact doses and forms are shown in the table.

Q: What do studies show about bones and falls?

Children whose mothers received cholecalciferol during pregnancy had higher bone density at primary school age than after placebo [116]. In children and young adults with HIV, a relatively high daily dose improved bone density in a meta-analysis [50]. For falls in independently living older people, one meta-analysis and two controlled studies found no difference [10, 94, 145]. Three meta-analyses, by contrast, found fewer falls, depending on dose, daily administration and baseline levels [4, 5, 6]. Fewer bone fractures appeared in one meta-analysis only when vitamin D was given together with calcium [6].

Vitamin D: What 339 human studies show, including 228 randomized controlled trials – ordered by area of application and strength of evidence.

Last updated: 2026-10-15

We evaluated 339 human studies on Vitamin D, including 228 randomised controlled trials and 88 meta-analyses or systematic reviews; the controlled studies include 142,839 participants in total. As of 3 October 2026.

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1. What Is Vitamin D? Occurrence, Origin and Forms

Vitamin D is a group of fat-soluble vitamins, the most important being vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol). The body makes vitamin D3 itself in the skin when it is exposed to the sun's UVB radiation; the liver and kidneys convert it into the storage form 25-hydroxyvitamin D and the active hormone form.

Food provides little vitamin D, mainly from oily sea fish, cod liver oil, egg yolk and mushrooms exposed to UV light. At our latitudes, sunlight in the winter half-year is hardly enough for the body's own production.

Vitamin D3 for supplements is mostly obtained from wool fat (lanolin), for vegan products from lichen; vitamin D2 is made from yeast or fungi. Studies test daily, weekly or infrequent high single doses.

Forms and Preparations Studied

Vitamin D3 (cholecalciferol) as capsule, tablet or drops
Vitamin D2 (ergocalciferol)
Calcifediol (25-hydroxyvitamin D) taken by mouth
Vitamin D combined with calcium, vitamin K2 or omega-3
Sunlight and UVB light for the body's own production

Not covered on this page:

Active vitamin D hormones and analogues as medicines (calcitriol, alfacalcidol, paricalcitol) in kidney and parathyroid disease
Topical vitamin D analogues for psoriasis (calcipotriol)

2. What Does Vitamin D Do? Results by Area

Area	Result in controlled studies	Strength of evidence	Studies	Participants
Infections and immune system	mostly improved	high	19 meta-analyses · 40 controlled · 6 other	7,232
Bones, falls and fractures	mixed	high	6 meta-analyses · 41 controlled · 8 other	11,754
Blood sugar and metabolism	mixed	high	14 meta-analyses · 31 controlled · 6 other	46,556
Heart, circulation and blood pressure	mostly no difference	high	11 meta-analyses · 30 controlled · 3 other	26,146
Mood and depression	mostly improved	high	5 meta-analyses · 17 controlled · 0 other	4,067
Pregnancy and children	mixed	high	5 meta-analyses · 10 controlled · 5 other	5,476
Autoimmune diseases	mostly improved	high	4 meta-analyses · 3 controlled · 1 other	416
Muscle strength	mostly improved	moderate	2 meta-analyses · 19 controlled · 3 other	3,004
Cancer risk and course	mixed	low	0 meta-analyses · 7 controlled · 1 other	22,796
Other outcomes	mostly improved	high	41 meta-analyses · 171 controlled · 22 other	57,783

How to read the table: counted are human studies whose results concern the area. “High” means at least one meta-analysis and two controlled studies showing improvement, or at least three controlled studies of which three quarters show improvement, with at least 300 participants in total. “Moderate” means at least two controlled studies showing improvement, as a majority, or one meta-analysis alongside controlled studies. “Low” means one controlled study showing improvement. Where an area has no controlled study, the strength of evidence is at most “low” (result “reviews only” or “observational data only”). Everything else is “unclear”. A study counts as showing improvement when at least half of its outcomes in this area improved. Reviews of combination products do not count as meta-analyses; results that only describe side effects or shares of users do not count as an effect. The same study is counted only once.

3. What the Studies Show in Detail

Vitamin D, Infections and Immune System: Human Studies

For COVID-19, mortality under vitamin D was lower in two meta-analyses and one controlled study, but not robust in one meta-analysis 31 53 225. In this meta-analysis, ICU admission and ventilation remained without a difference 53, and one review warns that small studies overestimate the benefit 84. In children with asthma, severe attacks decreased in a meta-analysis compared with placebo and in a controlled study under a higher dose 46 191. Inflammation markers such as CRP fell more strongly in meta-analyses in type 2 diabetes and in dialysis patients than under control 36 64. Overall, vitamin D did not prevent respiratory infections in children in two meta-analyses and one controlled study 13 24 134, but in schoolchildren in winter the number of days of illness fell 159. Vitamin D did not prevent tuberculosis in one meta-analysis 14. Investigated were predominantly oral vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol) preparations as well as calcifediol. The results depend on form, dose and baseline levels, and many studies were small or short.

Study	Design · participants	Preparation · dose · duration · comparison	Result
2 Chen et al. 2021	meta-analysis · 536,105 participants	Vitamin D supplements (form not specified); vs. placebo/control or higher vs. lower vitamin D levels	COVID-19 infection risk with vitamin D deficiency <20 ng/ml: no difference (OR for < 20 ng/ml: 1.61, 95% CI: 0.92-2.80); in-hospital death with vitamin D deficiency <20 ng/ml: no difference (OR for < 20 ng/ml: 2.18, 95% CI: 0.91-5.26); in-hospital death with vitamin D insufficiency <30 ng/ml: no difference (OR for < 30 ng/ml: 3.07, 95% CI: 0.64-14.78)
9 Wang et al. 2024	meta-analysis · 35,160 participants	Vitamin D supplements; vs. Placebo	Antibiotic use in the general population: no difference (OR = 0.98, p = 0.232); Antibiotic use in elderly participants: no difference (OR = 0.98, p = 0.295); Antibiotic use in participants under 70 years: improved (OR = 0.95, p = 0.015)
11 Meng et al. 2025	meta-analysis · 19,586 participants	Vitamin D supplementation; vs. Placebo or standard treatment	tuberculosis infection (prevention): unclear (RR 0·75; 95% CI 0·56 to 1·01); sputum smear conversion: no difference; sputum culture conversion: no difference
13 Wang et al. 2025	meta-analysis · 18,372 participants	Oral vitamin D supplementation; Daily low-dose ≤ 1000 IU/day vs. higher doses; vs. Placebo or no treatment	ARI incidence: no difference (RR = 0.82, 95% CI: 0.64 to 1.06); Hospitalization duration: no difference (MD = 0.03 days, 95% CI: -0.72 to 0.78); Recovery time: no difference (MD = -4.36 h, 95% CI: -11.87 to 3.15)
14 Liu et al. 2025	meta-analysis · 15,677 participants	Vitamin D supplementation; vs. Placebo	Risk of tuberculosis infection: no difference (OR: 0.95; 95% CI: 0.79-1.14; p = 0.55); Development of active tuberculosis: no difference (OR: 0.77; 95% CI: 0.56-1.05; p = 0.10)
17 Hsu et al. 2026	systematic review · 11,600 participants	Vitamin D supplements (form not reported); vs. Placebo or control in included RCTs	IL-10 in asthma: unclear (Hedges'g = 18.85, p = 0.04)
18 Patchen et al. 2025	systematic review · 10,611 participants	vitamin D (form not specified); 200 IU/day to 100,000 IU bolus quarterly; 28 days to two years; vs. placebo/no supplementation or low/standard dose (≤400 IU/day)	childhood airway infections (pregnant/breastfeeding women): no difference (RR 1.00, 95% CI 0.97 to 1.04; 3 studies, 1564 participants; moderate-certainty evidence)
21 Goswami et al. 2025	systematic review · 4,415 participants	Vitamin D for prophylaxis; 1000 IU or 5000 IU; 4 to 16 weeks; vs. Placebo or lower dose	Influenza-like illness: improved; Respiratory infections: no difference

Further studies in this area: 24 28 31 32 36 46 52 53 64 66 75 77 84 97 102 108 134 143 147 149 150 155 156 159 163 169 180 191 198 203 207 214 225 226 227 237 238 239 245 256 262 269 273 280 285 287 292 295 296 306 309 317 318 326 327 328 336

Vitamin D, Bones, Falls and Fractures: Human Studies

Children whose mothers received cholecalciferol during pregnancy had higher bone density at primary school age than after placebo 116. In children and young adults with HIV, a relatively high daily dose improved bone density in a meta-analysis 50. For falls in independently living older people, one meta-analysis and two controlled studies found no difference 10 94 145. Three meta-analyses, by contrast, found fewer falls, depending on dose, daily administration and baseline levels 4 5 6. Fewer bone fractures appeared in one meta-analysis only when vitamin D was given together with calcium 6. The strength of evidence in the table is high, but the results depend strongly on form, dose and accompanying supplementation; it remains open which groups and dosages actually benefit.

Study	Design · participants	Preparation · dose · duration · comparison	Result
4 Wei et al. 2022	meta-analysis · 61,350 participants	Vitamin D supplement, partly with calcium; high-dose ≥700 IU to 2000 IU daily vs. <700 IU; vs. placebo or no treatment	fall incidence (high-dose vitamin D): improved (RR, 0.87 (95% CI 0.79 to 0.96)); fall incidence (low-dose vitamin D): no difference
5 Tan et al. 2024	meta-analysis · 58,937 participants	Vitamin D, calcium, or combined supplementation; 800-1000 IU/day vs. >1000 IU/day; vs. Placebo, no treatment, calcium alone	Fall risk with 800-1000 IU/day vitamin D: improved (RR = 0.85, 95%CI: 0.74-0.95); Fall risk with daily 800-1000 IU/day: improved (RR = 0.78, 95%CI:0.64-0.92); Fall risk with intermittent administration: no difference
6 Thanapluetiwong et al. 2020	meta-analysis · 58,424 participants	Vitamin D supplement, partly with calcium; vs. Placebo or control in RCTs	Fall incidence: improved (RR = 0.948 (95% CI 0.914-0.984; P = .004, I = 41.52)); Fall incidence (vitamin D with calcium): improved (RR = 0.881 (95% CI 0.821-0.945; P < .001, I = 49.19)); Fractures: no difference (RR = 0.949 (95% CI 0.846-1.064; P = .37, I = 37.92))
7 Cong et al. 2025	meta-analysis · 43,869 participants	vitamin D plus calcium; vs. control/placebo	bone mineral density at the pelvis: improved (SMD = 0.20, 95% CI: 0.05–0.35, p = 0.01); BMD at lumbar spine, femoral neck, total hip: no difference; fracture risk: no difference (RR = 0.98, 95% CI: 0.89–1.07, p = 0.68)
8 Migliorini et al. 2025	systematic review · 43,397 participants	Vitamin D and/or calcium supplementation; mean 92.8 ± 228.7 IU vitamin D and 833.6 ± 224.0 mg calcium daily; mean follow-up 25.8 ± 13.3 months; vs. different doses or two or more treatments	bone mineral density (spine, hip, femur neck): no difference; serum bone turnover markers (bone-ALP, NTX, CTX): no difference; pathological vertebral and non-vertebral fractures: no difference
10 Torres-Lopez et al. 2025	meta-analysis · 23,211 participants	vitamin D supplements; ≤1000 IU/day vs. >1000 IU/day, daily or intermittent; ≤12 months vs. >12 months; vs. placebo or control	fall risk: no difference (OR = 0.99; 95%CI: 0.95-1.03); fall risk in women: no difference (OR = 0.97; 95%CI: 0.92-1.02); fall risk in men: no difference (OR = 1.08; 95%CI: 0.98-1.20)
16 Yang et al. 2021	meta-analysis · 11,890 participants	Vitamin D (DMOAD class); at least 12 months follow-up; vs. other DMOAD classes or control	Pain: improved (- 0.15 [- 0.27, -0.03]); Function: improved (- 0.18 [- 0.31, - 0.06])
50 Nguyen et al. 2023	meta-analysis · 966 participants	Vitamin D supplementation (ergocalciferol or cholecalciferol); 400 to 7000 IU/d; higher dose 1600-4000 IU/d vs. standard 400-800 IU/d; 6 to 24 months; vs. Placebo or higher vs. standard dose	Spine BMD at 12 months: no difference (SMD: -0.09; 95% CI: -0.47, 0.3; P = 0.65); Total BMD at 12 months, higher vs. standard dose: improved (SMD: 0.23; 95% CI: 0.02, 0.44; P = 0.03); Spine BMD at 12 months, higher vs. standard dose: unclear (SMD: 0.3; 95% CI: -0.02, 0.61; P = 0.07)

Further studies in this area: 56 64 77 80 83 94 95 104 112 116 117 119 121 122 143 145 148 151 152 157 160 170 179 181 185 204 216 227 235 236 243 254 266 267 268 270 273 278 279 286 289 297 302 312 315 316 332

Vitamin D, Blood Sugar and Metabolism: Human Studies

In adults with type 2 diabetes and in women with polycystic ovary syndrome, several controlled studies showed improvements in fasting glucose, HbA1c and insulin resistance under oral vitamin D3 (cholecalciferol) 36 60 261. Markers of beta cell function such as C-peptide and HOMA-β developed more favorably compared with the control in type 2 diabetes, prediabetes and newly detected type 1 diabetes in children 241 299 301. Under ergocalciferol, by contrast, stimulated C-peptide in young people with new type 1 diabetes remained without a difference 280. In contrast, the large randomized studies in adults without diabetes found no difference in newly occurring type 2 diabetes 89 90. In healthy people, HbA1c, lipoproteins and BMI remained without a difference 21. In fatty liver disease, there was no difference in insulin resistance, fasting glucose and fasting insulin 62. In adult men with type 2 diabetes, insulin resistance, fasting glucose, insulin, HbA1c and lipid profile remained without a difference 298. In several studies, supplementation raised the vitamin D level in the blood 27 215 280 299. Investigated were predominantly oral vitamin D3 preparations, sometimes vitamin D2 (ergocalciferol). In women with polycystic ovary syndrome, insulin resistance and fasting glucose improved in a meta-analysis, more strongly with metformin than under vitamin D alone 52. One study compared low and higher dosed vitamin D3 with calcium citrate and found no difference between the doses for markers of insulin resistance 154. Vitamin D3 together with whey protein and strength training resulted in no difference in HbA1c and insulin resistance 163. It remains open which patient groups and which dose or form actually benefit, since the results are inconsistent between populations and measured variables.

Study	Design · participants	Preparation · dose · duration · comparison	Result
17 Hsu et al. 2026	systematic review · 11,600 participants	Vitamin D supplements (form not reported); vs. Placebo or control in included RCTs	CRP in abnormal glucose homeostasis: improved (Hedges'g = - 0.67); TNF-α in abnormal glucose homeostasis: improved (Hedges'g = - 0.81); IL-6 in abnormal glucose homeostasis: improved (Hedges'g = - 1.93)
20 Kretschmer et al. 2025	meta-analysis · 4,478 participants	oral vitamin D supplementation; study duration 0.5 to 5 years, at least 6 months; vs. placebo	Regression to normal glucose regulation: improved (1.27 (95% CI, 1.12-1.45))
21 Goswami et al. 2025	systematic review · 4,415 participants	Vitamin D for prophylaxis; 1000 IU or 5000 IU; 4 to 16 weeks; vs. Placebo or lower dose	Hemoglobin-A1c, lipoproteins, BMI: no difference
23 Martinekova et al. 2025	meta-analysis · 4,084 participants	Vitamin D supplementation; 6 to 12 months follow-up; vs. Control group without vitamin D	HOMA-IR: improved (MD, -0.31; 95% CI, -0.62 to -0.01); Triglycerides: improved (MD, -7.59 mg/dL; 95% CI, -15.09 to -0.81); Insulin: improved (MD -0.79 μIU/L; 95% CI, -1.36 to -0.21)
27 Gong et al. 2025	meta-analysis · 3,460 participants	Vitamin D supplementation; 500 IU to 60,000 IU; 3 to 12 months; vs. Control group	Serum 25(OH)D: improved (SMD: 4.01; 95% CI: 2.43 to 5.59; p < 0.001); HbA1c: no difference (SMD: 0.08; 95% CI: -0.25 to 0.37); HOMA-IR: no difference (SMD: 5.95; 95% CI: -2.87 to 14.77)
35 Hu et al. 2023	meta-analysis · 2,362 participants	Vitamin D as nutritional supplement; vs. Placebo and other nutritional supplements	Total cholesterol (TC): improved
36 M et al. 2026	meta-analysis · 2,000 participants	Vitamin D supplementation; vs. Placebo or control in randomized trials	HbA1c: improved (MD = −0.42%, 95% CI: −0.32 to −0.16; I² = 27%); Fasting blood glucose: improved (MD = −9.5 mg/dL; I² = 16%); HOMA-IR: improved (MD = −0.98; I² = 60%)
51 Liu et al. 2026	meta-analysis · 962 participants	vitamin D supplementation; higher daily doses, particularly up to 5,000 IU/day; vs. placebo	BMI, weight, and IL-6: no difference

Further studies in this area: 52 60 62 66 71 73 77 78 89 90 128 149 150 154 157 163 175 176 180 187 205 215 216 224 236 238 241 261 263 264 265 276 278 279 280 291 298 299 301 323 330 337 339

Vitamin D, Heart, Circulation and Blood Pressure: Human Studies

For heart, circulation and blood pressure, results without a difference predominate. Several controlled studies found no change in blood pressure under vitamin D 21 90 107 157 187 228. Cardiovascular mortality also remained unchanged in several controlled studies 86 109 139. One meta-analysis showed a lower frequency of postoperative atrial fibrillation in patients after coronary bypass surgery 58. Individual blood lipid values improved in reviews in type 2 diabetes and diabetic kidney disease 36 39 77, but not in overweight children and adolescents 73. The evidence is overall high, since numerous controlled studies and meta-analyses are available. It remains open whether certain groups or dosages do benefit.

Study	Design · participants	Preparation · dose · duration · comparison	Result
1 An et al. 2022	meta-analysis · 883,627 participants	Vitamin D supplementation; vs. Control group without vitamin D	Cardiovascular or type 2 diabetes risk: no difference (no effect)
3 Fu et al. 2022	meta-analysis · 86,202 participants	Vitamin D supplements (cholecalciferol, ergocalciferol, calcifediol); various dosages, subgroup analysis; various follow-up periods; vs. placebo	risk of stroke: no difference (RR = 1.02, 95% CI: 0.93-1.13, P = 0.65)
21 Goswami et al. 2025	systematic review · 4,415 participants	Vitamin D for prophylaxis; 1000 IU or 5000 IU; 4 to 16 weeks; vs. Placebo or lower dose	Cholesterol: improved (5000 IU Vitamin D for four weeks significantly reduced cholesterol, unlike 1000 IU for 16 weeks); Blood pressures: no difference
32 Pilkey et al. 2023	systematic review · 2,489 participants	native vitamin D (D2/D3); mostly short follow-up; vs. control/placebo in randomized trials	cardiovascular disease: unclear
36 M et al. 2026	meta-analysis · 2,000 participants	Vitamin D supplementation; vs. Placebo or control in randomized trials	LDL cholesterol: improved (MD = −5.85 mg/dL; I² = 22%); Triglycerides: improved (MD = −6.51 mg/dL; I² = 0%)
39 Lu et al. 2024	meta-analysis · 1,711 participants	Vitamin D supplementation; higher doses more favorable (subgroup analysis); shorter intervention more favorable (subgroup analysis); vs. control/placebo in 20 RCTs	HDL cholesterol: improved (MD: 1.63 mg/dL, 95% CI: 0.19 to 3.08, P = 0.03); triglycerides: improved (MD: -8.56 mg/dL, 95% CI: -15.23 to -1.89, P = 0.01); LDL cholesterol: no difference
58 Nisa et al. 2026	meta-analysis · 694 participants	Vitamin D supplementation; vs. Placebo or control	Incidence of postoperative atrial fibrillation: improved (RR: 0.55; 95% CI: 0.40 to 0.76; P=0.0003)
59 Ashraf et al. 2025	meta-analysis · 694 participants	Vitamin D supplementation; vs. Control/placebo in 4 randomized trials	Incidence of postoperative atrial fibrillation: improved (RR: 0.55; 95% CI: 0.40 to 0.76; P = 0.0003)

Further studies in this area: 66 73 77 86 90 107 109 126 129 139 143 150 157 160 167 176 187 203 214 215 219 227 228 234 260 261 263 264 270 276 278 279 288 313 320 321

Vitamin D, Mood and Depression: Human Studies

In adults with diagnosed depression, vitamin D improved depressive symptoms compared with placebo in one meta-analysis and one controlled study 51 150. In women with premenstrual syndrome, vitamin D supplementation improved depression, but not anxiety 74. In adults with type 2 diabetes and depressive symptoms, cholecalciferol lowered the depression score more strongly than placebo 241. In perimenopausal women with vitamin D deficiency, cholecalciferol improved mood 208. In children with ADHD, vitamin D3 plus magnesium improved emotional problems 249 251. In the same group, vitamin D3 plus magnesium improved anxiety and shyness 250. Vitamin D3 together with zinc improved depressive symptoms in overweight adults 182. In children with autism spectrum disorder, vitamin D reduced irritability and hyperactivity compared with placebo 200. In contrast, a large randomized controlled study with vitamin D3 over several years found no difference in the frequency of newly occurring major depressive disorder 96. A randomized controlled study with cholecalciferol in addition to depression treatment found no difference in the MADRS score 140. In adolescents with vitamin D deficiency and depressive symptoms, vitamin D showed an advantage on only one of three depression scales; the inflammation marker CRP did not change this 220. In adults with chronic spinal cord injury, anxiety and depression remained without a difference under vitamin D3 273. A systematic review on native vitamin D (D2/D3) saw no difference in patient-reported well-being in adults with end-stage renal failure 32. The studies are often small and differ in dose, form and population. Vitamin D did not change the serotonin level in the blood in one meta-analysis 79.

Study	Design · participants	Preparation · dose · duration · comparison	Result
12 Park et al. 2026	systematic review · 18,628 participants	Vitamin D supplementation; 2,000 IU daily to 50,000 IU weekly; 6 months to 5.3 years; vs. Placebo or control	Depressive symptoms: improved (p < .050); Depressive symptoms (one trial): no difference; Depression incidence: no difference (hazard ratio, 0.97; 95% confidence interval, 0.87~1.09)
32 Pilkey et al. 2023	systematic review · 2,489 participants	native vitamin D (D2/D3); mostly short follow-up; vs. control/placebo in randomized trials	patient-reported well-being: no difference
51 Liu et al. 2026	meta-analysis · 962 participants	vitamin D supplementation; higher daily doses, particularly up to 5,000 IU/day; vs. placebo	change in depressive symptoms: improved (SMD: -0.98; 95% CI - 1.28 to -0.68; p < 0.001)
74 Zainab et al. 2026	meta-analysis · 436 participants	Vitamin D supplementation; vs. Placebo or standard care	Depression: improved (SMD: -0.78, 95% CI: -1.53, -0.02); Anxiety: no difference
79 Alimohammadi-Kamalabadi et al. 2024	meta-analysis · 356 participants	Vitamin D supplementation; some below 4000 IU/day; some 10 weeks or longer; vs. control group	serum serotonin levels: no difference (SMD: 0.24 ng/mL, 95% CI: -0.28, 0.75, p > 0.10)
96 Ahl et al. 2026	randomised controlled · 2,434 participants	Vitamin D3; 1600 IU/day or 3200 IU/day; 5 years supplementation, follow-up until end of 2021; vs. Placebo	Incidence of major depressive disorder during 5 years: no difference (HR, 0.78; 95 % CI 0.35-1.71; P = 0.53); Incidence of major depressive disorder during 5 years: no difference (HR, 0.57; 95 % CI 0.24-1.35; P = 0.20); Incidence of major depressive disorder during extended follow-up: no difference (HR, 0.61; 95 % CI 0.34-1.10; P = 0.10)
140 Mikola et al. 2026	randomised controlled · 281 participants	Vitamin D (cholecalciferol) as adjunct to existing depression treatment; 100 µg (4000 IU) daily versus 10 µg (400 IU) daily; six months; vs. high-dose versus low-dose vitamin D	change in MADRS score: no difference (Cohen's d = -0.09; 95% CI -0.32 to 0.14)
150 Porto et al. 2025	randomised controlled · 224 participants	vitamin D supplementation; 50,000 IU per week; six months; vs. placebo (n=112)	depressive symptoms: improved (p = 0.001); suicide risk: improved (p = 0.001)

Further studies in this area: 182 187 200 202 208 220 232 241 249 250 251 257 273 315

Vitamin D, Pregnancy and Children: Human Studies

A review with meta-analysis found less gestational diabetes and a somewhat higher birth weight 85. With cholecalciferol, spontaneous vaginal births occurred more often because instrumental delivery was less frequent 101. For preeclampsia, two meta-analyses found a lower risk 33 82. Another review and a controlled study saw no difference there 85 107. For gestational hypertension, no difference was shown 107, as was also the case for prematurity 85 101. The results depend on form, dose and baseline levels, and many studies were small.

Study	Design · participants	Preparation · dose · duration · comparison	Result
17 Hsu et al. 2026	systematic review · 11,600 participants	Vitamin D supplements (form not reported); vs. Placebo or control in included RCTs	MDA in pregnant women: improved (Hedges'g = - 0.46); TAC in pregnant women: improved (Hedges'g = 2.13); glutathione in pregnant women: improved (Hedges'g = 4.37)
19 Shi et al. 2026	meta-analysis · 10,262 participants	Combined supplement with magnesium, zinc, calcium and vitamin D; vs. Standard control	cesarean section rate: no difference (RR = 0.44, 95% CI: 0.15, 1.29)
33 Kokkinari et al. 2025	meta-analysis · 2,461 participants	Vitamin D supplementation during pregnancy; heterogeneous, not specified; not reported; vs. no supplementation (RCT control groups)	risk of pre-eclampsia: improved (RR = 0.61, 95% CI: [0.50-0.75], p < 0.001)
76 Saha et al. 2020	meta-analysis · 380 participants	Vitamin D containing supplements; vs. Placebo	Risk of cesarean section: improved (RR: 0.61, p=0.002, 95% CI: 0.44,0.83); Risk of macrosomia: improved (RR: 0.31, p=0.006, 95% CI: 0.13,0.72); Pre-eclampsia, preterm delivery, polyhydramnios: no difference
82 Wang et al. 2026	meta-analysis	Oral nutritional supplements, including vitamin D; vs. Placebo and calcium	Preeclampsia: improved (OR=0. 34, 95% CI 0.17, 0.65); Gestational hypertension: no difference
85 Yang et al. 2025	systematic review	Vitamin D supplements; Median 2000 IU/day (range 400-60 000); vs. Placebo, no intervention, or active control (≤600 IU/day)	Risk of preeclampsia: no difference (RR, 0.81 [95% CI, 0.43-1.53]); Risk of gestational diabetes mellitus: improved (RR, 0.65 [95% CI, 0.49-0.86); Infant birth weight: improved (53 g (95% CI, 16-90))
99 Subramanian et al. 2025	randomised controlled · 1,298 participants	Vitamin D3 supplement; 4200, 16,800 or 28,000 IU per week; from mid-pregnancy until birth; vs. placebo	placental VEGF-A expression: no difference; placental PlGF expression: no difference; number and surface area of terminal villi: no difference
101 Moon et al. 2023	randomised controlled · 965 participants	Cholecalciferol 1000 IU/day; 1000 IU daily; from 14 weeks' gestation until delivery; vs. placebo, double-blind randomized	preterm birth: no difference (cholecalciferol 5.7%, placebo 4.5%, P = 0.43); spontaneous vaginal delivery: improved (RR 1.13, 95% CI 1.02,1.25); instrumental delivery: improved (RR 0.68, 95%CI 0.51,0.91)

Further studies in this area: 103 106 107 133 149 175 183 198 311 323 325 331

Vitamin D and Autoimmune Diseases: Human Studies

In systemic lupus erythematosus, vitamin D reduced disease activity and improved complement values C3 and C4 in a meta-analysis 55. In rheumatoid arthritis, disease activity and pain decreased compared with the control group 211. In clinically isolated syndrome, an early form of multiple sclerosis, cholecalciferol reduced MRI activity and new lesions compared with placebo, but not relapses 132. A meta-analysis in multiple sclerosis found a lower annual relapse rate only at low to medium dose, with no overall difference 49. A systematic review of vitamin D3 and/or vitamin D2 saw protection against autoimmune reactions 21. In a large placebo-controlled study, vitamin D reduced the number of confirmed autoimmune diseases over five years, while omega-3 fatty acids alone did not significantly 305. These are contrasted by results showing no difference: The EDSS score remained unchanged in the MS meta-analysis 49. In lupus, no differences were shown in erythrocyte sedimentation rate and anti-dsDNA levels 55. Another lupus meta-analysis found no difference in either the disease activity index or anti-dsDNA positivity 70. The evidence is strong, but the studies tested different forms and doses, and the participant numbers of the individual controlled studies remain partly small 132 211.

Study	Design · participants	Preparation · dose · duration · comparison	Result
21 Goswami et al. 2025	systematic review · 4,415 participants	Vitamin D for prophylaxis; 1000 IU or 5000 IU; 4 to 16 weeks; vs. Placebo or lower dose	Protection against autoimmune reactions: improved
49 Zhang et al. 2025	meta-analysis · 1,078 participants	Vitamin D supplementation; low/medium dose vs. high dose (subgroups); vs. intervention group vs. control group	Annualized relapse rate (ARR): no difference (pooled MD = -0.07, 95%CI [-0.18,0.03], Z = -1.37, p = 0.17); Annualized relapse rate, low/medium dose: improved (pooled MD = -0.14, 95%CI [-0.26, -0.03], p = 0.01); Annualized relapse rate, high dose: no difference (pooled MD = 0.05, 95%CI [-0.08, 0.18], p = 0.42)
55 Lu et al. 2026	meta-analysis · 847 participants	Vitamin D supplementation; vs. Control group (placebo/standard care)	Disease activity in SLE: improved (SMD = -0.54, p < 0.001); Complement component C3: improved (MD = 14.49, p = 0.03); Complement component C4: improved (SMD = 2.08, p = 0.04)
70 Zheng et al. 2019	meta-analysis · 490 participants	Vitamin D supplementation; vs. Placebo	SLE disease activity index score: no difference (SMD = -0.507, 95% CI: -1.055-0.041, P = 0.070); Positivity of anti-double-stranded DNA antibodies: no difference (Risk ratio = 0.880, 95% CI: 0.734-1.054, P = 0.165)
132 Thouvenot et al. 2025	randomised controlled · 316 participants	oral cholecalciferol 100 000 IU vs placebo; 100 000 IU every 2 weeks; 24 months; vs. placebo, double-blind randomized	disease activity (relapse and/or MRI activity): improved (HR, 0.66 [95% CI, 0.50-0.87]; P = .004); MRI activity: improved (HR, 0.71 [95% CI, 0.53-0.95]; P = .02); new lesions: improved (HR, 0.61 [95% CI, 0.44-0.84]; P = .003)
211 Rexhepi et al. 2025	randomised controlled · 100 participants	Vitamin D 4000 IU/day; 4000 IU/day; 6 months; vs. RA patients without vitamin D supplementation	Disease activity (DAS28): improved (U'=2285.5; P < 0.0001)
305 Hahn et al. 2022	randomised controlled	Vitamin D (2000 IU/day) or placebo, plus omega 3 fatty acids or placebo; 2000 IU/day vitamin D; 1000 mg/day omega 3 fatty acids; median 5.3 years follow-up; vs. placebo (two-by-two factorial design)	Confirmed autoimmune disease (vitamin D arm vs placebo): improved (hazard ratio 0.78, 95% confidence interval 0.61 to 0.99, P=0.05); Confirmed autoimmune disease (omega 3 arm vs placebo): no difference (0.85, 0.67 to 1.08, P=0.19); Confirmed autoimmune disease (vitamin D plus omega 3 vs reference arm): improved (0.69, 0.49 to 0.96)
335 Basti et al. 2026	cohort study · 101 participants	Vitamin D3 supplementation; increase by 1000 IU/day, maximum 2000 IU/day; 12 months; vs. patients with low vs normal baseline 25(OH)D	12-month disease relapse: no difference (7.3% vs 10%; p=0.64); relapses in patients who corrected vitamin D deficiency: improved (no relapses)

Vitamin D and Muscle Strength: Human Studies

In adults with chronic intestinal failure and vitamin D deficiency, intramuscularly administered ergocalciferol (vitamin D2) improved handgrip strength, 6-meter walking speed and skeletal muscle mass index 300. Children of mothers who received daily cholecalciferol during pregnancy had more lean mass at primary school age than after placebo 116. Together with exercise training, knee extension strength increased compared with training alone in a meta-analysis, and handgrip strength increased in older adults 40. A review found better values on the Short Physical Performance Battery and stair climbing 42. In older people with sarcopenia, vitamin D3 in addition to thermotherapy and strength training improved muscle mass and handgrip strength 180. In contrast, several controlled studies found no difference in hand and grip strength with administration of cholecalciferol or ergocalciferol alone 178 217 273, and vitamin D3 together with omega-3 fatty acids also did not change grip strength, walking speed and functional tests 100. The evidence is moderate; the results depend strongly on the form, the combination with training or protein and the group studied; whether supplementation alone, without accompanying measures, increases muscle strength remains open.

Study	Design · participants	Preparation · dose · duration · comparison	Result
32 Pilkey et al. 2023	systematic review · 2,489 participants	native vitamin D (D2/D3); mostly short follow-up; vs. control/placebo in randomized trials	muscle strength/function: unclear
37 Serag et al. 2025	meta-analysis · 1,903 participants	Vitamin D supplements as add-on therapy; Subgroup analysis: treatment longer than 12 months; vs. Controls	Timed 25-foot walk: no difference (p = 0.54)
40 Kazeminasab et al. 2025	meta-analysis · 1,675 participants	vitamin D plus exercise; vitamin D dose in IU/wk, variable; vs. exercise alone	leg press strength: no difference (P > .05); knee extension strength: improved (WMD, 4.36 kg; P = .039); handgrip strength: improved
42 Zhang et al. 2025	systematic review · 1,483 participants	Vitamin D3 supplementation combined with exercise training; vs. Exercise intervention alone	Short Physical Performance Battery: improved; Stair climbing: improved; Skeletal muscle mass: no difference
63 Chang et al. 2023	meta-analysis · 637 participants	Whey protein, leucine, and vitamin D; vs. Control group without nutritional supplementation	Appendicular muscle mass: improved (significantly improved); Handgrip strength: no difference (no significant differences); SPPB score: no difference (no significant differences)
100 Chou et al. 2024	randomised controlled · 1,054 participants	Vitamin D3 (cholecalciferol) and/or marine omega-3 fatty acids vs placebo; 2000 IU/day vitamin D3; 1 g/day omega-3; 2 years; vs. placebo, 2x2 factorial design	grip strength: no difference; walking speed: no difference; Short Physical Performance Battery: no difference
116 Moon et al. 2024	randomised controlled · 454 participants	Cholecalciferol 1000 IU/d or placebo; 1000 IU per day; from 14-17 wk gestation until delivery; vs. Placebo	Lean mass: improved (0.09 SD, 95% CI: 0.00, 0.17)
163 Miller et al. 2021	randomised controlled · 198 participants	Whey protein plus vitamin D3, with progressive resistance training; 20 g whey protein each morning and postexercise; vitamin D3 2000 IU/day; 24 weeks; vs. Resistance training without supplementation	30-s sit-to-stand performance: improved (1.0 [95% CI, -0.05, 1.5], p = .047)

Further studies in this area: 173 176 178 180 189 201 214 217 238 248 263 264 273 295 300 312

Vitamin D, Cancer Risk and Course: Human Studies

In cancer diseases, a mixed picture emerges: A randomized controlled study in patients with advanced cervical cancer undergoing radiotherapy found a higher rate of complete remissions with cholecalciferol 190, and another randomized controlled study in women with breast cancer before neoadjuvant chemotherapy reports pathological complete remission more often 231. In curatively resected gastrointestinal tumors, cholecalciferol improved recurrence-free survival in subgroups with low parathyroid hormone levels, while no difference occurred in the group with high parathyroid hormone levels 123; in digestive tract cancer, the effect on recurrence or death depended on vitamin A levels, with benefit at medium levels and disadvantage at the lowest levels 130. In contrast, the largest randomized controlled study in older adults found no difference in cancer incidence 91, and in curatively resected cutaneous melanoma, cholecalciferol showed no advantage in either recurrence-free survival or melanoma mortality 118. The evidence is overall low: The controlled studies are mostly small, concern different tumor types and treatment situations, and the positive findings come predominantly from subgroup or single studies; cholecalciferol was mostly studied as a capsule or tablet, sometimes daily, sometimes as a single dose. It remains open whether and for which tumor types and baseline levels administration actually helps.

Study	Design · participants	Preparation · dose · duration · comparison	Result
91 Neale et al. 2025	randomised controlled · 21,308 participants	Vitamin D3 or placebo; 60,000 IU per month; up to 5 years; vs. placebo	cancer incidence (at least one cancer diagnosis): no difference (HR 1.02; 95 % CI 0.95-1.10); cancer incidence excluding cutaneous melanomas: no difference (HR 1.04; 95 % CI 0.95-1.14)
118 De et al. 2024	randomised controlled · 436 participants	Cholecalciferol (vitamin D3); 100 000 IU monthly; minimum 6, maximum 42 months; median follow-up 52 months; vs. Placebo (218 vs. 218)	Relapse-free survival at 72 months: no difference (26.51% in the vitamin D supplemented arm (95% CI 19.37-35.64) vs. 20.70% (95% CI 14.26-29.52) in the placebo arm (hazard ratio 1.27, 95% CI 0.79-2.03; P = 0.32)); Melanoma-related deaths: no difference (n = 10 and n = 11, respectively)
123 Sasaki et al. 2026	randomised controlled · 410 participants	Vitamin D3 versus placebo; 2000 IU/day; maximum follow-up 7.5 years; vs. placebo, randomized double-blind	relapse-free survival (lower PTH subgroup): improved (HR, 0.45; 95% CI, 0.24-0.81; p = 0.008); relapse-free survival (higher PTH subgroup): no difference (HR, 1.25; 95% CI, 0.64-2.44; p for interaction = 0.016); relapse-free survival (low PTH and p53-positive): improved (HR, 0.38; 95% CI, 0.18-0.78; p = 0.009)
130 Kohmura et al. 2026	randomised controlled · 363 participants	Vitamin D3 supplementation versus placebo; 5-year relapse-free survival; vs. Placebo	Relapse or death (5-year RFS) in middle vitamin A range (deciles 6-8): improved (81.4% vs. 54.9%; HR, 0.31; 95% CI, 0.14-0.69; P = 0.004); Relapse or death in lowest vitamin A decile (decile 1): worsened (HR, 2.05; 95% CI, 1.10-3.84; P = 0.03); Interaction vitamin A x vitamin D on relapse or death: unclear (Pinteraction = 0.008)
190 Suardi et al. 2025	randomised controlled · 123 participants	Cholecalciferol; 10 000 IU daily; 7 weeks during and 12 weeks after radiotherapy; vs. Placebo plus same radiotherapy protocol	complete response rate: improved (82.61% in the Treatment group and 64.8% in the Control group)
231 Omodei et al. 2025	randomised controlled · 80 participants	Cholecalciferol 2,000 IU daily vs. placebo; 2,000 IU daily; 6 months; vs. placebo	Pathological complete response (pCR): improved (43% vs. 24%, p = 0.04)
237 Tirgar et al. 2024	randomised controlled · 76 participants	Vitamin D alone, synbiotics alone, or their combination vs. placebo; four months; vs. Placebo	pathological complete response (pCR): no difference; Ki-67 index: no difference
321 Yao et al. 2026	cohort study · 3,995 participants	serum 25-hydroxyvitamin D levels (no supplementation); median follow-up 12.2 years (0.2-16.3); vs. sufficient versus deficient vitamin D levels	overall survival: improved (HR, 0.76; 95% CI, 0.62-0.93; P for trend =.005); second primary cancer-free survival: improved (HR, 0.75; 95% CI, 0.63-0.90; P for trend =.003); disease-free survival: improved (HR, 0.82; 95% CI, 0.70-0.97; P for trend =.05)

Vitamin D: Further Outcomes in Studies

In this area, numerous controlled studies and meta-analyses investigated very different outcome measures; the evidence is strong, but the results vary widely depending on the outcome. The storage form 25(OH)D in blood reliably increased, for example in meta-analyses in multiple sclerosis, lupus and fatty liver disease 49 55 62. In diabetic foot ulcer, wounds healed more often than with control in a meta-analysis 66. Calcium, phosphate and urinary calcium values remained without difference between the groups in several studies 64 119 174 204; in two studies, serum calcium increased 149 267. Cholecalciferol (vitamin D3), ergocalciferol (vitamin D2) and calcifediol were predominantly studied as a capsule, tablet, drops or injection. It remains open which dose, form and treatment duration is actually of benefit for which patient group, since the studies included very different populations and comparison groups.

Study	Design · participants	Preparation · dose · duration · comparison	Result
7 Cong et al. 2025	meta-analysis · 43,869 participants	vitamin D plus calcium; vs. control/placebo	serum 25-hydroxyvitamin D: improved (Z = 10.48, p < 0.001)
8 Migliorini et al. 2025	systematic review · 43,397 participants	Vitamin D and/or calcium supplementation; mean 92.8 ± 228.7 IU vitamin D and 833.6 ± 224.0 mg calcium daily; mean follow-up 25.8 ± 13.3 months; vs. different doses or two or more treatments	gastrointestinal adverse events (r = - 0.5; P = 0.02); mortality: improved (r = - 0.7; P = 0.03)
11 Meng et al. 2025	meta-analysis · 19,586 participants	Vitamin D supplementation; vs. Placebo or standard treatment	tuberculosis score at 8 weeks: improved (MD - 0·39; 95% CI -0·57 to -0 22); tuberculosis score at 12 weeks: improved (MD - 0·53; 95% CI - 0·84 to - 0·22); TB score at 8 weeks (daily dosing): improved
13 Wang et al. 2025	meta-analysis · 18,372 participants	Oral vitamin D supplementation; Daily low-dose ≤ 1000 IU/day vs. higher doses; vs. Placebo or no treatment	All-cause mortality: no difference (RR = 0.88, 95% CI: 0.60 to 1.28); Serious adverse events (RR = 0.83, 95% CI: 0.71 to 0.96)
14 Liu et al. 2025	meta-analysis · 15,677 participants	Vitamin D supplementation; vs. Placebo	Serious adverse events (OR: 1.02; 95% CI: 0.76-1.38; p = 0.87)
15 Matukaitienė et al. 2025	systematic review · 13,000 participants	Vitamin D (level measurement or supplementation); vs. Men with mild vs. moderate-to-severe or arteriogenic ED; supplementation vs. control	Serum vitamin D levels in moderate-to-severe or arteriogenic ED: worsened (significantly lower serum VD levels); Erectile function with low vitamin D status: worsened (poorer erectile function scores); ED prevalence with vitamin D deficiency: worsened (independently associated with higher ED prevalence)
17 Hsu et al. 2026	systematic review · 11,600 participants	Vitamin D supplements (form not reported); vs. Placebo or control in included RCTs	inflammatory markers in obesity/asthma: no difference
18 Patchen et al. 2025	systematic review · 10,611 participants	vitamin D (form not specified); 200 IU/day to 100,000 IU bolus quarterly; 28 days to two years; vs. placebo/no supplementation or low/standard dose (≤400 IU/day)	early childhood asthma (pregnant/breastfeeding women): improved (RR 0.17, 95% CI 0.05 to 0.61; 1 study, 236 participants; low-certainty evidence)

Further studies in this area: 21 22 23 25 26 29 30 32 34 37 38 40 41 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 61 62 64 65 66 67 68 69 70 71 72 74 77 78 81 86 87 88 92 93 94 95 98 103 105 110 111 113 114 115 117 118 119 120 124 125 127 129 131 134 135 136 137 138 139 141 142 143 144 145 146 149 150 153 155 157 158 160 161 162 164 165 166 168 169 170 171 172 174 175 176 177 178 180 181 182 184 185 186 187 188 189 190 192 193 194 195 196 197 199 200 201 204 205 206 207 208 209 210 211 212 213 214 216 217 218 219 221 222 223 224 225 226 227 228 229 230 231 232 233 236 239 240 241 242 244 245 246 247 248 249 250 251 252 253 254 255 256 258 259 260 261 263 264 265 267 268 270 271 272 273 274 275 276 277 279 281 282 283 284 285 287 288 290 291 293 294 295 296 297 298 299 300 301 302 303 304 306 307 308 309 310 311 312 314 315 317 318 319 322 324 329 332 333 334 338

4. How Is Vitamin D Dosed? Preparation, Dose and Duration in Studies

The studies used predominantly oral preparations with cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2), sometimes calcifediol, as a capsule, tablet, drops or injection. Some studies tested vitamin D together with calcium, vitamin K2, omega-3 fatty acids, magnesium, zinc or probiotics. The doses and intake schedules are shown in the table.

Preparation or form	Dose	Duration	Study
Vitamin D3 (cholecalciferol), 2000 IU/day, vs. placebo	2000 IU/day	median follow-up 5.3 years	89
oral vitamin D3, monthly dose	60,000 IU monthly	median 4.6 years follow-up	90
Vitamin D3 or placebo	60,000 IU per month	up to 5 years	91
Vitamin D (2000 IU/day) and/or omega-3 (1 g/day)	2000 IU vitamin D daily; 1 g omega-3 daily	median 5.3 years	92
Vitamin D (60,000 IU) or placebo monthly	60,000 IU per month	up to 5 years, assessed at 3 years	93
Vitamin D3 (cholecalciferol)	1600 IU/day or 3200 IU/day	5 years	94
Vitamin D3	1600 IU/day or 3200 IU/day	5 years supplementation, 7.3 years follow-up	95
Vitamin D3	1600 IU/day or 3200 IU/day	5 years supplementation, follow-up until end of 2021	96
oral vitamin D3	9600 IU/d for 2 d, then 3200 IU/d for 4 wk	4 weeks	97
Vitamin D3 2000 IU/d, partly combined with omega-3 fatty acids 1 g/d	2000 IU vitamin D3 daily; 1 g omega-3 daily	5 years	98
Vitamin D3 supplement	4200, 16,800 or 28,000 IU per week	from mid-pregnancy until birth	99
Vitamin D3 (cholecalciferol) and/or marine omega-3 fatty acids vs placebo	2000 IU/day vitamin D3; 1 g/day omega-3	2 years	100
Cholecalciferol 1000 IU/day	1000 IU daily	from 14 weeks' gestation until delivery	101
Oral vitamin D (cholecalciferol)	4000 or 10,000 IU/day versus 400 IU/day	up to 9 months	102
Vitamin D 4000 IU/day or placebo	4000 IU/day	up to 90 days until trigger day	103

5. Is Vitamin D Safe? Side Effects in Studies

Two meta-analyses found no more adverse events under vitamin D than under placebo, nor more cases of hypercalcemia 14 64. One review warns that very high doses can lead to hypercalcemia 21.

Study	Reported side effects
8 Migliorini et al. 2025	vitamin D associated with fewer gastrointestinal adverse events
11 Meng et al. 2025	similar safety profiles between the two groups
13 Wang et al. 2025	Fewer serious adverse events, RR = 0.83, 95% CI: 0.71 to 0.96
14 Liu et al. 2025	Serious adverse events comparable to placebo; none attributed to vitamin D
18 Patchen et al. 2025	evidence on adverse events very uncertain
21 Goswami et al. 2025	Concern for hypercalcemia at high doses mentioned
24 Jolliffe et al. 2025	not reported
26 Zhou et al. 2024	Vitamin D among three safest (SUCRA 0.19)
27 Gong et al. 2025	similar to control (RR 1.19; 95% CI 0.79 to 1.80)
32 Pilkey et al. 2023	safe and well-tolerated
33 Kokkinari et al. 2025	not reported
43 Chen et al. 2025	adverse events comparable (RR 1.02, 95% CI 0.94-1.10)

6. What Remains Open: Limits of the Evidence

The results depend strongly on form, dose and baseline levels, so it remains unclear which groups and dosages benefit.
Many controlled studies were small or short, which limits their informative value.
With combination preparations, the contribution of vitamin D alone often cannot be separated out.
For cancer diseases, the strength of evidence is low, since the studies are mostly small and concern different tumor types.
It remains open whether supplementation alone, without accompanying measures such as training or protein, increases muscle strength.

7. Bottom Line: What Is Established About Vitamin D

In human studies, vitamin D shows a broad spectrum of effects. Controlled studies and meta-analyses found improvements above all in depressive symptoms, disease activity of autoimmune diseases, asthma attacks in children and inflammation markers. Muscle strength mostly increased only together with training. For bones, metabolism, heart and cancer, the results are mixed or predominantly without a difference, for example for blood pressure, falls and cancer incidence. The strength of evidence is overall high, but the results depend strongly on form, dose and population, and many studies were small or short.

Frequently Asked Questions

How well has Vitamin D been studied in humans?

Does Vitamin D help with infections and immune system? What the studies show

We evaluated 19 meta-analyses or systematic reviews, 40 controlled studies and 6 further studies; the controlled studies include 7,232 participants in total. Result of the controlled studies: mostly improved. Strength of evidence under our published rules: high. Sources: 2 9 11 13

Does Vitamin D help with bones, falls and fractures? What the studies show

We evaluated 6 meta-analyses or systematic reviews, 41 controlled studies and 8 further studies; the controlled studies include 11,754 participants in total. Result of the controlled studies: mixed. Strength of evidence under our published rules: high. Sources: 4 5 6 7

Does Vitamin D help with blood sugar and metabolism? What the studies show

We evaluated 14 meta-analyses or systematic reviews, 31 controlled studies and 6 further studies; the controlled studies include 46,556 participants in total. Result of the controlled studies: mixed. Strength of evidence under our published rules: high. Sources: 17 20 21 23

Does Vitamin D help with heart, circulation and blood pressure? What the studies show

We evaluated 11 meta-analyses or systematic reviews, 30 controlled studies and 3 further studies; the controlled studies include 26,146 participants in total. Result of the controlled studies: mostly no difference. Strength of evidence under our published rules: high. Sources: 1 3 21 32

Does Vitamin D help with mood and depression? What the studies show

We evaluated 5 meta-analyses or systematic reviews and 17 controlled studies; the controlled studies include 4,067 participants in total. Result of the controlled studies: mostly improved. Strength of evidence under our published rules: high. Sources: 12 32 51 74

Does Vitamin D help with pregnancy and children? What the studies show

We evaluated 5 meta-analyses or systematic reviews, 10 controlled studies and 5 further studies; the controlled studies include 5,476 participants in total. Result of the controlled studies: mixed. Strength of evidence under our published rules: high. Sources: 17 19 33 76

Which forms of vitamin D were investigated in the studies?

The studies used predominantly oral preparations with cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2), sometimes calcifediol. Some studies tested vitamin D together with calcium, vitamin K2, omega-3 fatty acids, magnesium, zinc or probiotics. The exact doses and forms are shown in the table.

Do human studies show an effect on the immune system?

For COVID-19, mortality under vitamin D was lower in two meta-analyses and one controlled study, but not robust in one meta-analysis 31 53 225. In children with asthma, severe attacks decreased 46 191, but overall vitamin D did not prevent respiratory infections in children 13 24 134.

What do studies show about bones and falls?

How safe is vitamin D?

Two meta-analyses found no more adverse events under vitamin D than under placebo, nor more cases of hypercalcemia 14 64. One review warns that very high doses can lead to hypercalcemia 21. In one study, kidney stones occurred in some of the participants, without a clear difference between the groups 98.

Are there limitations of the studies?

The results depend strongly on form, dose and baseline levels, so it remains unclear which groups and dosages benefit. Many controlled studies were small or short. With combination preparations, the contribution of vitamin D alone often cannot be separated out. For cancer diseases, the strength of evidence is low.

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Cong B, Zhang H · 2025
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Migliorini F, Maffulli N, Colarossi G, Filippelli A, Memminger M, Conti V · 2025
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Safety and efficacy of antioxidant therapy in children and adolescents with attention deficit hyperactivity disorder: A systematic review and network meta-analysis
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Pilkey NG, Novosel O, Roy A, Wilson TE, Sharma J, Khan S et al. · 2023
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The Role of Vitamin D Supplementation in Preventing Pre-Eclampsia: A Review of Randomized Controlled Trials with Meta-Analysis
Kokkinari A, Antoniou E, Orovou E, Andronikidi PE, Tzitiridou-Chatzopoulou M, Sarantaki A et al. · 2025
34
Administration of vitamin D and its metabolites in critically ill adult patients: an updated systematic review with meta-analysis of randomized controlled trials
Menger J, Lee ZY, Notz Q, Wallqvist J, Hasan MS, Elke G et al. · 2022
35
Comparison of nutritional supplements in improving glycolipid metabolism and endocrine function in polycystic ovary syndrome: a systematic review and network meta-analysis
Hu X, Wang W, Su X, Peng H, Tan Z, Li Y et al. · 2023
36
Vitamin D Supplementation Improves Glycemic Control, Inflammation, and Lipid Profile in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
M M, AU H · 2026
37
Role of vitamin D as adjuvant therapy on multiple sclerosis: an updated systematic review and meta-analysis of randomized controlled trials
Serag I, Abouzid M, Alsaadany KR, Hendawy M, Ali HT, Yaseen Y et al. · 2025
38
Evaluation of the Clinical Outcomes Associated With the Use of Fatty Acids and Vitamin D in Rheumatoid Arthritis Patients: A Systematic Review and Meta-Analysis
Xu B, Liang D, Chen G · 2025
39
The effects of vitamin D supplementation on serum lipid profiles in people with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials
Lu Q, Liang Q, Xi Y · 2024
40
Effects of Vitamin D Supplementation in Combination With Exercise Training on Body Composition and Muscular Strength in Adults: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials
Kazeminasab F, Moein AR, Baharlooie M, Moradi S, Camera DM, Tinsley GM et al. · 2025
41
Preoperative Calcium or Vitamin D Supplement in Thyroidectomy: A Systematic Review and Meta-Analysis
Jullamusi W, Ratanaprasert N, Pongsapich W, Kasemsuk N · 2025
42
Exercise combined with vitamin D supplementation has additive health effects on short physical performance battery and stair climbing in older adults: a scope review of randomised controlled trials
Zhang J, Zhu Z, Niu Y, Cao ZB · 2025
43
Effectiveness and safety of dietary supplements in the adjunctive treatment of psoriasis: a systematic review and network meta-analysis
Chen D, Yang J, Yang W, Liu X, Li Z · 2025
44
Effect of Vitamin D Supplementation on Human Gut Microbiota: A Systematic Review of Randomized Controlled Trials
Zeb F, Osaili T, Hashim M, Alkalbani N, Papandreou D, Cheikh Ismail L et al. · 2026
45
The effect of vitamin D supplementation on hemoglobin concentration: a systematic review and meta-analysis
Arabi SM, Ranjbar G, Bahrami LS, Vafa M, Norouzy A · 2020
46
Vitamin D supplementation decrease asthma exacerbations in children: a systematic review and meta-analysis of randomized controlled trials
Fedora K, Setyoningrum RA, Aina Q, Rosyidah LN, Ni'mah NL, Titiharja FF · 2024
47
Effects of vitamin D supplementation on TSH and thyroid hormones: A systematic review of randomized controlled trials
Safari S, Shojaei-Zarghani S, Molani-Gol R, Rafraf M, Malekian M · 2025
48
Preoperative Vitamin D and Calcium Administration in Patients Undergoing Thyroidectomy: A Systematic Review and Meta-analysis of Randomized Controlled Trials
Alhakami M, Lajdam GB, Ghaddaf AA, Alayoubi S, Alhelali S, Alshareef M et al. · 2024
49
Vitamin D deficiency and multiple sclerosis relapse: a meta-analysis
Zhang Y, Yu S, Zu Y, Lv J, Chen J, Feng X · 2025
50
A Systematic Review and Meta-Analysis of Randomized Controlled Trials of the Effects of Vitamin D Supplementation on Children and Young Adults with HIV Infection
Nguyen HS, Van Tran K, Chen SY, Tam KW · 2023
51
Efficacy of vitamin D supplementation in patients diagnosed with depression: a dose-response meta-analysis of randomized controlled trials
Liu HH, Liu TH, Liu CY, Wu JY, Lin CH, Lai CC · 2026
52
Vitamin D Supplementation on Metabolic and Endocrine Profiles in Women with polyendocrine metabolic ovarian syndrome: An Updated Systematic Review and Meta-Regression of Randomized Controlled Trials
Pan D, Rui Z, Zhang W, Xia Y, Gao L, Yang L et al. · 2026
53
Vitamin D supplementation for managing COVID-19 in patients with vitamin D deficiency: a systematic review and meta-analysis of randomised controlled trials
Zhu L, Zhang Y, Li X, Zou X, Bing P, Qi M et al. · 2025
54
Vitamin D3 as an add-on treatment for multiple sclerosis: A systematic review and meta-analysis of randomized controlled trials
Mahler JV, Solti M, Apóstolos-Pereira SL, Adoni T, Silva GD, Callegaro D · 2024
55
Effects of vitamin D supplementation on patients with systemic lupus erythematosus: A systematic review and meta-analysis
Lu J, Zhu Q, Yu J, Tan Z, Kang Y, Sun Q et al. · 2026
56
Optimizing bone health in people living with HIV: insights from a network meta-analysis of randomized controlled trials
Wang JC, Chung SM, Wu PT, Tu YK, Lai PC, Tai TW et al. · 2025
57
Clinical Efficacy of Vitamin D Supplements for the Treatment of Anemia in Patients With Chronic Kidney Disease: A Systematic Review and Meta-Analysis
Wanyan X, Xu J · 2026
58
Effect of vitamin D on postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting: a systematic review and meta-analysis
Nisa F, Nauman HM, Lal PK, Assad AA, Arain M, Ali R et al. · 2026
59
Vitamin D supplementation among postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting: a systematic review and meta-analysis
Ashraf T, Moiz MA, Kumar G, Kumar A, Kumar V, Anand V et al. · 2025
60
The impact of vitamin D supplementation on glycemic control and lipid metabolism in polycystic ovary syndrome: a systematic review of randomized controlled trials
Yu M, Chen S, Liu X, Dong H, Wang DC · 2025
61
Vitamin D Supplementation for Treating Atopic Dermatitis in Children and Adults: A Systematic Review and Meta-Analysis
Nielsen AY, Høj S, Thomsen SF, Meteran H · 2024
62
The effect of vitamin D supplementation on some metabolic parameters in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis of 8 RCTs
Chen X, Zhao Y, Zhang R, Zhao Y, Dai L · 2023
63
Effects of Whey Protein, Leucine, and Vitamin D Supplementation in Patients with Sarcopenia: A Systematic Review and Meta-Analysis
Chang MC, Choo YJ · 2023
64
The role of nutritional vitamin D on microinflammation and nutritional status in maintenance hemodialysis patients: a meta-analysis of randomized controlled trials
Li C, Xu S, Wang Y, Wu M · 2026
65
The Effect of Vitamin D Supplementation on the Severity of Symptoms and the Quality of Life in Irritable Bowel Syndrome Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Abuelazm M, Muhammad S, Gamal M, Labieb F, Amin MA, Abdelazeem B et al. · 2022
66
Effects of vitamin D supplementation on diabetic foot ulcer healing: a meta-analysis
Wu X, Zeng J, Ye X, Peng M, Lan Y, Zhang S et al. · 2025
67
Efficacy of weekly versus daily cholecalciferol for repleting serum vitamin D (25(OH)D) deficiency: A systematic review and meta-analysis of randomized controlled trials
Bortolussi-Courval É, Prosty C, Lee JJ, McCarthy LM, McDonald EG, Lee TC · 2024
68
Efficacy of Weekly versus Daily Cholecalciferol for Repleting Vitamin D (1,25-Dihydroxy Vitamin D) Deficiency: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Bortolussi-Courval É, Prosty C, Lee JJ, McCarthy L, McDonald E, Lee TC · 2024
69
Efficacy and Safety of Intralesional Purified Protein Derivative Versus Vitamin D for the Treatment of Cutaneous Warts: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Abu-Zaid A, Hilali S, Albasheer Z, Alkhatlan S, Alraqum FF, Al-Rashid AH et al. · 2026
70
Efficacy and Safety of Vitamin D Supplementation in Patients With Systemic Lupus Erythematosus: A Meta-analysis of Randomized Controlled Trials
Zheng R, Gonzalez A, Yue J, Wu X, Qiu M, Gui L et al. · 2019
71
Vitamin D supplementation in individuals with type 1 diabetes mellitus (T1DM): a systematic review and meta-analysis focusing on pediatrics
Fan S, Zhang T, Yin L · 2025
72
Effects of Dietary Supplementation in Patients with Restless Legs Syndrome: A Systematic Review
González-Parejo P, Martín-Núñez J, Cabrera-Martos I, Valenza MC · 2024
73
Can vitamin D supplementation affect cardiometabolic factors in children and adolescence with overweight and obesity? A grade-assessed systematic review and meta-analysis of randomized controlled trials
Faghfouri AH, Mahmoudinezhad M, Pam P, Barazandeh S, Faramarzi F, Mohammadpour Y et al. · 2025
74
Efficacy of Vitamin D Supplementation to Alleviate Premenstrual Syndrome Symptoms: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Zainab A, Tageldin RS, Patel R, Hassan MA, Aburas LA, Alkahily M et al. · 2026
75
Insufficient evidence for vitamin D use in COVID-19: A rapid systematic review
da Rocha AP, Atallah AN, Aldrighi JM, Pires ALR, Dos Santos Puga ME, Pinto ACPN · 2021
76
A comparison of the risk of cesarean section in gestational diabetes mellitus patients supplemented antenatally with vitamin D containing supplements versus placebo: A systematic review and meta-analysis of double-blinded randomized controlled trials
Saha S, Saha S · 2020
77
Are There Any Pleiotropic Benefits of Vitamin D in Patients With Diabetic Kidney Disease? A Systematic Review of Randomized Controlled Trials
Sharma JK, Khan S, Wilson T, Pilkey N, Kapuria S, Roy A et al. · 2023
78
The effect of magnesium alone or its combination with other supplements on the markers of inflammation, OS and metabolism in women with polycystic ovarian syndrome (PCOS): A systematic review
Li R, Li Z, Huang Y, Hu K, Ma B, Yang Y · 2022
79
Does vitamin D supplementation impact serotonin levels? A systematic review and meta-analysis
Alimohammadi-Kamalabadi M, Ziaei S, Hasani M, Mohammadi S, Mehrbod M, Morvaridi M et al. · 2024
80
Effects of vitamin D on biochemical markers of osteoporosis: a meta-analysis of randomised trials
Alber CS, Halsey J, Emberson J, Hin H, Hill M, Armitage J et al. · 2026
81
Psoriasis and Vitamin D: A Systematic Review and Meta-Analysis
Formisano E, Proietti E, Borgarelli C, Pisciotta L · 2023
82
Nutritional supplements for preventing preeclampsia: A network meta-analysis
Wang C, You C, Zhang Y · 2026
83
Calcium, vitamin D, or combined supplementation to prevent fractures and falls: systematic review and meta-analysis
Massé O, Mercurio CM, Dupuis S, Al Sahwi M, Arruda A, Dallaire G et al. · 2026
84
Vitamin D, acute respiratory infections, and Covid-19: The curse of small-size randomised trials. A critical review with meta-analysis of randomised trials
Autier P, Doi G, Mullie P, Vankrunkelsven P, D'Ecclesiis O, Gandini S · 2025
85
The Effects of Vitamin D Supplementation During Pregnancy on Maternal, Neonatal, and Infant Health: A Systematic Review and Meta-analysis
Yang WC, Chitale R, O'Callaghan KM, Sudfeld CR, Smith ER · 2025
86
Vitamin D Supplementation and Its Impact on Mortality and Cardiovascular Outcomes: Systematic Review and Meta-Analysis of 80 Randomized Clinical Trials
Ruiz-García A, Pallarés-Carratalá V, Turégano-Yedro M, Torres F, Sapena V, Martin-Gorgojo A et al. · 2023
87
The effect of vitamin D supplementation on serum levels of fibroblast growth factor- 23: A systematic review and meta-analysis of randomized controlled trials
Meshkini F, Soltani S, Clark CCT, Tam V, Meyre D, Toupchian O et al. · 2022
88
Vitamin D Food Fortification and Biofortification Increases Serum 25-Hydroxyvitamin D Concentrations in Adults and Children: An Updated and Extended Systematic Review and Meta-Analysis of Randomized Controlled Trials
Dunlop E, Kiely ME, James AP, Singh T, Pham NM, Black LJ · 2021
89
Vitamin D supplementation vs. placebo and incident type 2 diabetes in an ancillary study of the randomized Vitamin D and Omega-3 Trial
Tobias DK, Pradhan AD, Duran EK, Li C, Song Y, Buring JE et al. · 2025
90
Effect of Vitamin D Supplementation on Cardiometabolic Outcomes in Older Australian Adults-Results from the Randomized Controlled D-Health Trial
Duarte Romero BL, Armstrong BK, Baxter C, English DR, Ebeling PR, Hartel G et al. · 2026
91
The effect of vitamin D supplementation on cancer incidence in the randomised controlled D-Health Trial: Implications for policy and practice
Neale RE, English DR, McLeod DS, Armstrong BK, Baxter C, Romero BD et al. · 2025
92
The effect of vitamin D and omega-3 fatty acid supplementation on pain prevalence and severity in older adults: a large-scale ancillary study of the VITamin D and OmegA-3 triaL (VITAL)
Soens MA, Sesso HD, Manson JE, Fields KG, Buring JE, Lee IM et al. · 2024
93
The effect of three years of vitamin D supplementation on erectile dysfunction: Results from the randomized placebo-controlled D-Health Trial
Duarte Romero B, Waterhouse M, Baxter C, McLeod DSA, English DR, Armstrong BK et al. · 2024
94
The Effect of Vitamin D3 Supplementation on the Risk of Falls in a General Population-The Finnish Vitamin D Trial
Rikkonen T, Hantunen S, Kröger H, Lamberg-Allardt C, Manson JE, Nurmi T et al. · 2026
95
The effect of vitamin D3 supplementation on fracture incidence in an aging population - The Finnish vitamin D trial
Rikkonen T, Hantunen S, Kröger H, Lamberg-Allardt C, Manson JE, Nurmi T et al. · 2026
96
Vitamin D supplementation and incidence of major depressive disorder - A randomized clinical trial
Ahl NM, Hantunen S, Tuomainen TP, Lamberg-Allardt C, Manson JE, Nurmi T et al. · 2026
97
A Randomized Trial of Vitamin D Supplementation and COVID-19 Clinical Outcomes and Long COVID: The Vitamin D for COVID-19 Trial
Ganmaa D, Cook KA, Khudyakov P, Enkhjargal D, Bilegtsaikhan T, Mayer KH et al. · 2026
98
Effect of Vitamin D and Omega-3 Fatty Acid Supplementation on Kidney Function in Patients With Type 2 Diabetes: A Randomized Clinical Trial
de Boer IH, Zelnick LR, Ruzinski J, Friedenberg G, Duszlak J, Bubes VY et al. · 2019
99
Effect of vitamin D3 supplementation starting mid-pregnancy on placental angiogenic factors and terminal villi: a secondary analysis of a randomized controlled trial in Bangladesh
Subramanian A, Carr CM, Papp E, Murphy KE, Al Mahmud A, Roth DE et al. · 2025
100
Effects of Supplemental Vitamin D3, Omega-3 Fatty Acids on Physical Performance Measures in the VITamin D and OmegA-3 TriaL
Chou SH, Cook NR, Kotler G, Kim E, Copeland T, Lee IM et al. · 2024
101
Does antenatal cholecalciferol supplementation affect the mode or timing of delivery? Post hoc analyses of the MAVIDOS randomized controlled trial
Moon RJ, D'Angelo S, Crozier SR, Curtis EM, Fernandes M, Kermack AJ et al. · 2023
102
Effect of moderate or high versus low dose daily vitamin D on COVID-19 incidence: A double-blind, parallel-group randomized clinical trial
Meltzer DO, Moy JN, Schram AW, Tate A, Hyman MJ, Cursio JF et al. · 2026
103
Vitamin D supplementation before in vitro fertilisation in women with polycystic ovary syndrome: multicentre, double blind, placebo controlled, randomised clinical trial
Hu KL, Liao T, Wu Q, Ma X, Cao Y, Tan J et al. · 2026
104
Impact of high-dose vitamin D and calcium carbonate supplementation on bone density in adolescents living with HIV: a randomised, placebo-controlled trial
Ferrand RA, Dzavakwa NV, Bandason T, Chisenga M, Filteau S, Kranzer K et al. · 2026
105
Effect of vitamin D and omega-3 fatty acid supplementation on anemia incidence among older adults: the VITAL trial
Cho HL, Li C, Manson JE, Cook NR, Lee IM, Buring JE et al. · 2025
106
Higher Maternal Body Mass Index Attenuates the Response to High-Dose Vitamin D Supplementation During Pregnancy: A Secondary Analysis of the Randomized Vitamin D Antenatal Asthma Reduction Trial (VDAART)
Jung C, Lu Z, Handy DE, Litonjua AA, Loscalzo J, Weiss ST et al. · 2026
107
The effect of pregnancy vitamin D supplementation on maternal blood pressure: real-world data analysis within the MAVIDOS randomised placebo-controlled trial
Citeroni-Clark NL, D'Angelo S, Crozier SR, Kermack A, Godfrey KM, Cooper C et al. · 2025
108
Maternal antenatal vitamin D supplementation and offspring risk of atopic eczema in the first 4 years of life
El-Heis S, D’Angelo S, M EC, Healy E, J RM, Crozier S et al. · 2024
109
Targeted vitamin D supplementation and major adverse cardiovascular events after myocardial infarction: the TARGET-D trial
May HT, Le VT, Anderson JL, Iverson L, Bair TL, Knight S et al. · 2026
110
Effect of daily sunscreen application on vitamin D: findings from the open-label randomized controlled Sun-D Trial
Tran V, Duarte Romero BL, Andersen H, Clarke M, Collins LG, Dawson T et al. · 2025
111
Impact of Vitamin D Supplementation on Cognition in Adults With Mild to Moderate Vitamin D Deficiency: Outcomes From the VitaMIND Randomized Controlled Trial
Corbett A, Taylor R, Llewellyn D, Ranson JM, Hampshire A, Pickering E et al. · 2025
112
Vitamin D supplementation and bone health in post-menopausal women: a 24-month randomized controlled intervention with enhanced bioavailability formulations
Rasool N, Munir Y · 2026
113
Calcium and vitamin D reduce hypoparathyroidism and hospital stay after thyroidectomy: A randomized controlled trial
Gkanis V, Nastos K, Ntalaperas K, Agianni E, Lainas S, Raikou P et al. · 2026
114
High-Dose Vitamin D3 Supplementation During Pregnancy and Test-Based Cognitive Performance at Age 10 Years: A Post Hoc Secondary Analysis of a Randomized Clinical Trial
Frederiksen OF, Jepsen JRM, Brustad N, Vinding R, Rosenberg JB, Mohammadzadeh P et al. · 2026
115
Vitamin D and wound healing: Assessing skin barrier function and implications for chloasma treatment
Chen Q, Liu L, Zhang Y · 2024
116
Pregnancy vitamin D supplementation and offspring bone mineral density in childhood follow-up of a randomized controlled trial
Moon RJ, D' Angelo S, Curtis EM, Ward KA, Crozier SR, Schoenmakers I et al. · 2024
117
Pregnancy vitamin D supplementation and bone mineral density of the mother: a post hoc analysis of the MAVIDOS randomised placebo-controlled trial
Moon RJ, D'Angelo S, Curtis EM, Ward KA, Godfrey KM, Cooper C et al. · 2025
118
High-dose vitamin D supplementation does not improve outcome in a cutaneous melanoma population: results of a randomized double-blind placebo-controlled study (ViDMe trial)
De Smedt J, Van Kelst S, Janssen L, Marasigan V, Boecxstaens V, Bogaerts K et al. · 2024
119
Rationale for Raising Current Clinical Practice Guideline Target for Serum 25-Hydroxyvitamin D in Chronic Kidney Disease
Strugnell SA, Sprague SM, Ashfaq A, Petkovich M, Bishop CW · 2019
120
Use of Extended-Release Calcifediol to Treat Secondary Hyperparathyroidism in Stages 3 and 4 Chronic Kidney Disease
Sprague SM, Crawford PW, Melnick JZ, Strugnell SA, Ali S, Mangoo-Karim R et al. · 2016
121
Effects of a 1-year calcium-enriched permeate supplement on bone health in postmenopausal females: The RENEW randomized controlled intervention trial
Tetens I, Kisi SB, Parlesak A, Rasmussen SI, Cramon MØ, Petersen CF et al. · 2026
122
Baseline 25-hydroxyvitamin D levels predict the effects of vitamin D supplementation on joint symptoms and cartilage loss in patients with knee osteoarthritis
Wang T, Zheng S, Jin X, Cen H, Zhu Z, Han W et al. · 2025
123
Parathyroid Hormone Modifies the Effect of Vitamin D Supplementation on Risk of Relapse or Death in Patients with Digestive Tract Cancer: A Post Hoc Subgroup Analysis of the AMATERASU Randomized Clinical Trial
Sasaki A, Akutsu T, Ohdaira H, Suzuki Y, Eto K, Urashima M · 2026
124
Effects of Vitamin D3 Combined with Folic Acid on Domain and Specific Cognitive Function among Patients with Mild Cognitive Impairment: A Randomized Clinical Trial
Liu W, Zheng D, Li X, Wang T, Wang L, Hao L et al. · 2024
125
Analysis of the Efficacy and Safety of Weekly Calcifediol 100 µg in Vitamin D Deficient Patients
Pérez Castrillón JL, Jódar-Gimeno E, Molina K, García-Bea A, Ostalé CM, Gilaberte I · 2025
126
Vitamin K2 and D3 Supplementation in Patients With Severe Coronary Artery Calcification: The DANCODE Trial
Hasific S, Øvrehus KA, Mejldal A, Hosbond S, Lambrechtsen J, Kumarathurai P et al. · 2026
127
Efficacy and Safety of Weekly Calcifediol Formulations (75 and 100 µg) in Subjects with Vitamin D Deficiency: A Phase II/III Randomised Trial
Jódar-Gimeno E, Pérez-Castrillón JL, Nociar J, Lojka M, Nikolov D, Cereto-Castro F et al. · 2024
128
One-Year Comparison of Three Maintenance Doses of Vitamin D₃ (600, 1000, and 2000 IU/day) on Metabolic Outcomes in Overweight and Obese Children: A Post-Hoc Analysis of a Randomized Trial
Nourian NZ, Bina AH, Nemati M, Asghari G · 2026
129
Vitamin K2 and D in Patients With Aortic Valve Calcification: A Randomized Double-Blinded Clinical Trial
Diederichsen ACP, Lindholt JS, Möller S, Øvrehus KA, Auscher S, Lambrechtsen J et al. · 2022
130
Effect Modification by Serum Vitamin A Levels on the Association between Vitamin D and Relapse or Death in Patients with Digestive Tract Cancer
Kohmura T, Ohdaira H, Suzuki Y, Urashima M · 2026
131
Genetic determinants of response to vitamin D supplementation
Alonso N, Schoenmakers I, Kuenzer T, Willems A, Jin H, Aspray TJ et al. · 2026
132
High-Dose Vitamin D in Clinically Isolated Syndrome Typical of Multiple Sclerosis: The D-Lay MS Randomized Clinical Trial
Thouvenot E, Laplaud D, Lebrun-Frenay C, Derache N, Le Page E, Maillart E et al. · 2025
133
Efficacy of a Personalized mHealth App in Improving Micronutrient Supplement Use Among Pregnant Women in Karachi, Pakistan: Parallel-Group Randomized Controlled Trial
Vadsaria K, Nuruddin R, Mohammed N, Azam I, Sayani S · 2025
134
Weekly Vitamin D Supplementation to Prevent Acute Respiratory Infections in Young Children at Different Latitudes: A Randomized Controlled Trial
Reyes ML, Vizcaya C, Le Roy C, Loureiro C, Brinkmann K, Arancibia M et al. · 2024
135
Long-Term Treatment and Effect of Discontinuation of Calcifediol in Postmenopausal Women with Vitamin D Deficiency: A Randomized Trial
Pérez-Castrillón JL, Dueñas-Laita A, Gómez-Alonso C, Jódar E, Del Pino-Montes J, Brandi ML et al. · 2023
136
Serum magnesium is linked with sperm concentration, motile sperm count and serum anti-Müllerian hormone in infertile men
Yahyavi SK, Probst-Drejer B, Poulsen NN, Jorsal MJ, Juul A, Jørgensen N et al. · 2026
137
Calcifediol is superior to cholecalciferol in improving vitamin D status in postmenopausal women: a randomized trial
Pérez-Castrillón JL, Dueñas-Laita A, Brandi ML, Jódar E, Del Pino-Montes J, Quesada-Gómez JM et al. · 2021
138
Intervention methods and influencing factors of vitamin D deficiency in Northeast China: a self-controlled trial and randomized controlled trial study
Liu J, Qu C, Jin S, Jia Y, Na L · 2026
139
Calcifediol supplementation in adults on hemodialysis: a randomized controlled trial
Morrone L, Palmer SC, Saglimbene VM, Perna A, Cianciolo G, Russo D et al. · 2022
140
Effect of a six-month vitamin D supplementation on depressive symptoms in patients with major depressive episode (DepFuD): a double-blinded randomised controlled trial
Mikola T, Lehto SM, Tolmunen T, Honkalampi K, Valkonen-Korhonen M, Laukkanen V et al. · 2026
141
The Effect of Vitamin D Supplementation with or without Calcium on Vitamin D Epimer and Metabolites
Gariballa S, Al-Bluwi GSM, Yasin J · 2024
142
A Randomized Phase II/III Trial Evaluating the Efficacy and Safety of 100 and 125 µg of Calcifediol Weekly Treatment of Severe Vitamin D Deficiency
Pérez-Castrillón JL, Jódar-Gimeno E, Nociar J, Lojka M, Nikolov D, Cereto-Castro F et al. · 2025
143
Ergocalciferol Supplementation in Hemodialysis Patients With Vitamin D Deficiency: A Randomized Clinical Trial
Miskulin DC, Majchrzak K, Tighiouart H, Muther RS, Kapoian T, Johnson DS et al. · 2016
144
Efficacy and Safety of High-Dose Vitamin D Supplementation Combined With an Enuresis Alarm vs Alarm Alone in Children With Primary Monosymptomatic Nocturnal Enuresis: A Randomized Clinical Trial
Ye Z, Luo X, Chen H, Zhang Q, Li C, Zhang Z et al. · 2026
145
Vitamin D and Falls in Older African American Women: The PODA Randomized Clinical Trial
Aloia JF, Rubinova R, Fazzari M, Islam S, Mikhail M, Ragolia L · 2019
146
Vitamin D Supplementation and Testosterone Levels in Breast Cancer Survivors
Minopoli A, Di Gennaro P, Porciello G, Palumbo E, Vitale S, Grimaldi M et al. · 2025
147
Impact of vitamin D status and supplementation on exploratory inflammatory biomarkers in preschoolers with asthma
El Abd A, Trottier H, Tse SM, Mâsse B, Mailhot G, Alos N et al. · 2026
148
Efficacy of Daily Supplementation of Milk Fortified With Vitamin D2 for Three Months in Healthy School Children: A Randomized Placebo Controlled Trial
Marwaha RK, Dabas A, Puri S, Kalaivani M, Dabas V, Yadav S et al. · 2021
149
The role of vitamin D in pregnancy outcomes in gestational diabetes: a randomized controlled trial
Liu Y, Luo L, Yu J, Yin Q · 2026
150
Randomized, placebo-controlled, double-blind clinical trial on the contributions of vitamin D in the control of cardiovascular risk factors, depressive symptoms and suicide risk
Porto C, Petribu K, Barbosa N, Magalhães R, Lira C, Porto AB et al. · 2025
151
The soy isoflavones for reducing bone loss (SIRBL) study: a 3-y randomized controlled trial in postmenopausal women
Alekel DL, Van Loan MD, Koehler KJ, Hanson LN, Stewart JW, Hanson KB et al. · 2010
152
Vitamin D supplementation during pregnancy and offspring bone microarchitecture: A post hoc analysis of the MAVIDOS randomised controlled trial
Maden C, D'Angelo S, Westbury LD, Curtis EM, Crozier SR, Godfrey KM et al. · 2026
153
Effect of Vitamin D Supplementation on (25(OH)D) Status in Children 12-30 Months of Age: A Randomized Clinical Trial
Flores-Aldana M, Rivera-Pasquel M, García-Guerra A, Pérez-Cortés JG, Bárcena-Echegollén JE · 2023
154
Vitamin D supplementation at low (600 IU/day) or higher dose (3,750 IU/day) does not improve insulin resistance markers at one year: A randomized controlled trial
Safwan N, Mantzoros CS, Rahme M, Baddoura R, Halaby G, El-Hajj Fuleihan G · 2025
155
The Immunomodulatory Activity of High Doses of Vitamin D in Critical Care Patients with Severe SARS-CoV-2 Pneumonia-A Randomized Controlled Trial
Gonçalves AM, Velho S, Rodrigues B, Antunes ML, Cardoso M, Godinho-Santos A et al. · 2025
156
Impact of vitamin D supplementation in the prognosis of patients with SARS-CoV2 pneumonia admitted to the intensive care unit - a randomized controlled trial
Gonçalves AM, Rodrigues BS, Antunes ML, Gonçalves J, Marinho A · 2025
157
Vitamin K status has no influence on the effect of vitamin D supplementation on bone turnover and cardiovascular markers: a randomized controlled trial
Theiler-Schwetz V, Riedmann U, Zelzer S, Meinitzer A, Schmitt L, Kraus DA et al. · 2026
158
Role of vitamin D supplementation and vitamin D receptor in drug-resistant epilepsy: A double-blind placebo-controlled trial conducted in India
Pattnaik SS, Sarangi SC, Dash Y, Singh A, Goswami R, Singh S et al. · 2025
159
Effects of vitamin D supplementation on acute respiratory tract infections in 6-8-year-old children: a randomized clinical trial
Clerico JW, Thams L, Stounbjerg NG, Hauger H, Damsgaard CT, Mølgaard C · 2025
160
Classification of Vitamin D Status Based on Vitamin D Metabolism: A Randomized Controlled Trial in Hypertensive Patients
Zelzer S, Meinitzer A, Enko D, Keppel MH, Herrmann M, Theiler-Schwetz V et al. · 2024
161
Lung and blood early biomarkers for host-directed tuberculosis therapies: Secondary outcome measures from a randomized controlled trial
Wallis RS, Ginindza S, Beattie T, Arjun N, Likoti M, Sebe M et al. · 2022
162
Effect of Monthly Vitamin D on Chronic Pain Among Community-Dwelling Seniors: A Randomized, Double-Blind Controlled Trial
Schlögl M, Chocano-Bedoya P, Dawson-Hughes B, Orav EJ, Freystaetter G, Theiler R et al. · 2019
163
Effects of whey protein plus vitamin D supplementation combined with progressive resistance training on glycaemic control, body composition, muscle function and cardiometabolic risk factors in middle-aged and older overweight/obese adults with type 2 diabetes: A 24-week randomized controlled trial
Miller EG, Nowson CA, Dunstan DW, Kerr DA, Menzies D, Daly RM · 2021
164
CAN PROTEIN AND VITAMIN D ENHANCE THE COGNITIVE BENEFITS OF RESISTANCE TRAINING IN TYPE 2 DIABETICS?
Macpherson H, Miller E, Dunstan D, Nowson C, Kerr D, Menzies D et al. · 2017
165
Vitamin D Supplementation Improves Cognitive Function Through Reducing Oxidative Stress Regulated by Telomere Length in Older Adults with Mild Cognitive Impairment: A 12-Month Randomized Controlled Trial
Yang T, Wang H, Xiong Y, Chen C, Duan K, Jia J et al. · 2020
166
Is urinary myelin basic protein the key to understanding the role of vitamin D supplementation in paediatric overactive bladder-dry? Results from a three-stage clinical investigation
Chen H, Zhang Z, Ye Z, Zhang Q, Zhang T, An N et al. · 2026
167
The effect of calcitriol and cholecalciferol on inflammatory markers in periprocedural myocardial injury: A randomized controlled trial
Mahmoudi L, Izadpanah P, Asadi S · 2025
168
Magnesium status and supplementation influence vitamin D status and metabolism: results from a randomized trial
Dai Q, Zhu X, Manson JE, Song Y, Li X, Franke AA et al. · 2018
169
REsCue trial: Randomized controlled clinical trial with extended-release calcifediol in symptomatic COVID-19 outpatients
Bishop CW, Ashfaq A, Melnick JZ, Vazquez-Escarpanter E, Fialkow JA, Strugnell SA et al. · 2023
170
Vitamin D Supplementation for Children with Epilepsy on Antiseizure Medications: A Randomized Controlled Trial
Bashiri FA, Hudairi A, Hamad MH, Al-Sulimani LK, Al Homyani D, Al Saqabi D et al. · 2024
171
Results From the REsCue Trial: A Randomized Controlled Trial with Extended-Release Calcifediol in Symptomatic Outpatients with COVID-19
Bishop CW, Ashfaq A, Melnick JZ, Vazquez-Escarpanter E, Fialkow JA, Strugnell SA et al. · 2022
172
The Effect of Vitamin D Supplementation on Functional Outcomes in Patients Undergoing Rehabilitation After an Ischemic Stroke: A Prospective, Single-Blind, Randomized, Placebo-Controlled Study
Borowicz W, Ptaszkowska L, Małecki R, Paprocka-Borowicz M · 2025
173
Effect of calcifediol and cholecalciferol on muscle function in postmenopausal women: a randomized controlled trial
Bischoff-Ferrari HA, Dawson-Hughes B, Orav JE, Ceglia L, Egli A, Kistler-Fischbacher M et al. · 2025
174
Safety and effectiveness of stoss therapy in children with vitamin D deficiency
Tannous P, Fiscaletti M, Wood N, Gunasekera H, Zurynski Y, Biggin A et al. · 2020
175
Effect of vitamin D combined with probiotic-assisted insulin pump on glucose-lipid metabolism, intestinal flora and pregnancy outcome in gestational diabetes mellitus
Chen M, Li C, Miao Z · 2026
176
Beneficial effects of exercise, testosterone, vitamin D, calcium and protein in older men-A randomized clinical trial
Midttun M, Overgaard K, Zerahn B, Pedersen M, Rashid A, Østergren PB et al. · 2024
177
Efficacy of vitamin D supplementation for children with acute bronchiolitis: A randomized controlled trial
Abdelkreem E, Labeeb YS, Mohamed MA · 2026
178
Cholecalciferol and muscle strength in hemodialysis patients: results from the randomized VITADIAL trial
Bataille S, Seret G, Lavainne F, Giaime P, Serveaux M, Robert T et al. · 2026
179
Increase in calcidiol level is associated with improved sternal bone healing after cardiac surgery with sternotomy-REINFORCE-D trial results
Černý D, Čečrle M, Sedláčková E, Míková B, Drncová E, Skalský I et al. · 2025
180
The effects of vitamin D combined with thermotherapy and resistance exercise on inflammatory factors, thyroid hormones and MSTN in elderly patients with sarcopenia
Zhao C, Liu W, Kong T, Zhu X, Wang R · 2025
181
High-dose versus low-dose ergocalciferol for correcting hypovitaminosis D after fragility hip fracture: a randomized controlled trial
Jarusriwanna A, Phusunti S, Chotiyarnwong P, Unnanuntana A · 2021
182
Effects of zinc, vitamin D, and their co-supplementation on mood, serum cortisol, and brain-derived neurotrophic factor in patients with obesity and mild to moderate depressive symptoms: A phase II, 12-wk, 2 × 2 factorial design, double-blind, randomized, placebo-controlled trial
Yosaee S, Soltani S, Esteghamati A, Motevalian SA, Tehrani-Doost M, Clark CCT et al. · 2020
183
Positive effect of low dose vitamin D supplementation on growth of fetal bones: A randomized prospective study
Vafaei H, Asadi N, Kasraeian M, Shahraki HR, Bazrafshan K, Namazi N · 2019
184
Effects of vitamin D status and supplementation on MASLD severity in individuals with overweight or obesity: a cross-sectional study and randomized controlled trial
Yu L, Wang X, Yang X, Xu X, Li J, Li C et al. · 2026
185
Comparison of three different daily doses of vitamin D3 in the treatment of nutritional rickets in Indian children under age 5 years: A randomized controlled trial
Dabas A, Marwaha RK, Goswami B, Batra R, Dayal D, Dabas V et al. · 2026
186
Combined Rehabilitation with Alpha Lipoic Acid, Acetyl-L-Carnitine, Resveratrol, and Cholecalciferolin Discogenic Sciatica in Young People: A Randomized Clinical Trial
Scaturro D, Vitagliani F, Tomasello S, Sconza C, Respizzi S, Letizia Mauro G · 2023
187
Sunshine Against Stress: A Randomised, Double-Blind, Placebo-Controlled Trial of Vitamin D Supplementation for Allostatic Load in a Conflict-Affected Population of Azad Jammu & Kashmir
Kayani JA, Saleem J, Alsanie SA, Faryal J, Ali F, Zeb I · 2026
188
Effects of personalized vitamin D3 on inflammation in colorectal cancer patients: a randomized trial
Gwenzi T, Weber ANR, Trares K, Vlaski T, Slavic M, Sha S et al. · 2026
189
Effect of oral nutritional supplements on physical functional performance in older patients at nutritional risk discharged with a rehabilitation plan: A randomised controlled trial
Jensen A, Ninh ED, Darlem BB, Haack LM, Møller CM, Knudsen AW et al. · 2026
190
Impact of Cholecalciferol Supplementation on Radiotherapy Outcomes in Advanced Cervical Cancer
Suardi D, Judistiani RTD, Rinaldi M, Trianasari N, Hidayat B, Lesmana R et al. · 2025
191
A randomized comparison of intramuscular high-dose versus oral maintenance vitamin D to prevent severe exacerbations in deficient/insufficient asthmatic children
Alansari K, Davidson BL, Holick MF · 2025
192
Effect of Vitamin D Supplementation on Psoriasis Severity in Patients With Lower-Range Serum 25-Hydroxyvitamin D Levels: A Randomized Clinical Trial
Jenssen M, Furberg AS, Jorde R, Wilsgaard T, Danielsen K · 2023
193
Independent Effects of Vitamin D on Leukocyte Telomere Length and Activity: An RCT in Asian Indian Women With Prediabetes
Bhatt SP, Pandey S, Misra A · 2025
194
Improved bioavailability of buccal nanoemulsion vitamin D compared to conventional oral supplementation in patients with inflammatory bowel disease: a randomized controlled trial
Kojecký V, Klhůfek J, Kianička B, Kohout P · 2025
195
Safety, tolerability, and gastrointestinal effect of a Bifidobacterium-based synergistic synbiotic in infants and toddlers
Jarman JB, Torres PJ, Baum C, Tinoco J, Sato H, Rasteiro CS et al. · 2026
196
Effect of calcifediol on chronic rhinosinusitis, a randomized clinical trial
Popko-Zagor M, Jandziak P, Sierdzinski J, Rusetska N, Sarnowska E · 2025
197
Intralesional measles, mumps, and rubella vaccine versus vitamin D for treatment of warts: A randomised clinical trial
Sallam M, Awad A, Hamdy S, State A · 2026
198
The effect of vitamin D supplementation and vaginal probiotics on fertility in women with recurrent implantation failure: A randomized clinical trial
Badihi E, Sharifi P, Moradi A, Kamrani A, Hassanzadeh A, Soltani-Zangbar MS et al. · 2025
199
Effect of vitamin D supplementation on asthma control in patients with vitamin D deficiency: the ACVID randomised clinical trial
Andújar-Espinosa R, Salinero-González L, Illán-Gómez F, Castilla-Martínez M, Hu-Yang C, Ruiz-López FJ · 2021
200
A randomised controlled trial of vitamin D and omega-3 long chain polyunsaturated fatty acids in the treatment of irritability and hyperactivity among children with autism spectrum disorder
Mazahery H, Conlon CA, Beck KL, Mugridge O, Kruger MC, Stonehouse W et al. · 2019
201
Effects of combined nutritional supplementation and exercise on proxy measures of muscle mass, strength, and function in older adults with sarcopenia: a 12-week multicentre RCT
Sun J, He M, Chen M, Chen Y, Yuan W, Song F et al. · 2025
202
The impact of vitamin D supplementation on depression and anxiety in young individuals with depression and vitamin D insufficiency/deficiency
Lee YT, Huang HC, Ko KT, Sun FJ, Lee TH, Liu HC et al. · 2026
203
Randomized double-blind placebo-controlled proof-of-concept trial of resveratrol for outpatient treatment of mild coronavirus disease (COVID-19)
McCreary MR, Schnell PM, Rhoda DA · 2022
204
Nutritional vitamin D supplementation in dialysis: a randomized trial
Bhan I, Dobens D, Tamez H, Deferio JJ, Li YC, Warren HS et al. · 2015
205
The Effect of Some Micronutrients Multi-Supplementation on Thyroid Function, Metabolic Features and Quality of Life in Patients Treating With Levothyroxine and Vitamin D: A Double-blind, Randomized Controlled Trial
Nikkhah M, Vafa M, Abiri B, Golgiri F, Sarbakhsh P, Alaei-Shahmiri F · 2024
206
Clinical efficacy of vitamin D combined with conventional therapy for sudden sensorineural hearing loss in patients with vitamin D deficiency: a randomized controlled trial
Shen X, Yang M, Tian J, Xie L, Feng N, Ma R · 2025
207
Effect of weekly vitamin D supplementation on the severity of atopic dermatitis and type 2 immunity biomarkers in children: A randomized controlled trial
Borzutzky A, Iturriaga C, Pérez-Mateluna G, Cristi F, Cifuentes L, Silva-Valenzuela S et al. · 2024
208
Effect of vitamin D supplementation on fatigue and mood among perimenopausal women
Ray P, Srivastava A, Jani P · 2026
209
Extended-release calcifediol for secondary hyperparathyroidism in Chinese adults with stage 3 or 4 chronic kidney disease: a randomized trial
Fang M, Hao Y, Mao H, Ren H, Liao X, Li X et al. · 2026
210
A study to assess the relationship between vitamin D3 levels and the risk of acute exacerbation in patients with chronic obstructive pulmonary disease
Lakra A, Singh B, Janmeja AK, Sharma V, Kumar A · 2025
211
Impact of vitamin D supplementation on disease activity and pain management in rheumatoid arthritis: a randomized double-blinded controlled study
Rexhepi M, Krasniqi B, Hoti K, Daci A, Rexhepi-Kelmendi B, Krasniqi S · 2025
212
A PROSPECTIVE STUDY OF COMMONLY UTILIZED REGIMENS OF VITAMIN D REPLACEMENT AND MAINTENANCE THERAPY IN ADULTS
Rafii DC, Ali F, Farag A, Iyer B, Otterbeck PE, Chaudhari R et al. · 2019
213
Co-Administration of Soy Isoflavones and Vitamin D in Management of Irritable Bowel Disease
Jalili M, Hekmatdoost A, Vahedi H, Poustchi H, Khademi B, Saadi M et al. · 2016
214
Protein-enriched diet, with the use of lean red meat, combined with progressive resistance training enhances lean tissue mass and muscle strength and reduces circulating IL-6 concentrations in elderly women: a cluster randomized controlled trial
Daly RM, O'Connell SL, Mundell NL, Grimes CA, Dunstan DW, Nowson CA · 2014
215
The interaction of vitamin D supplementation with Omentin-1 gene polymorphism on metabolic biomarkers, omentin-1 levels and anthropometric measures in women with prediabetes: A double-blind randomized controlled trial
Molani-Gol R, Rafraf M, Asghari Jafarabadi M, Aftabi-Yousefabad S, Shanehbandi D · 2025
216
Vitamin D supplementation in obese Sri Lankan children: a randomized controlled trial
Samaranayake DBDL, Adikaram SGS, Atapattu N, Kendaragama KMDLD, Senevirathne JTN, Jayasekera HD et al. · 2020
217
A randomized double-blinded placebo controlled trial of ergocalciferol 40,000 versus 100,000 IU per week for vitamin D inadequacy in institutionalized postmenopausal women
Mueangpaisarn P, Chaiamnuay S · 2020
218
Effects of 12-Week Multivitamin Supplementation on Serum Folate Levels in Pre-Menopausal Females
Osburn S, Roberson P, Medler J, Shake J, Arnold R, Alamdari N et al. · 2020
219
Vitamin D in the prevention of left ventricular remodelling after an acute myocardial infarction: a randomized clinical trial
Tuñón J, Rodríguez-López C, Balaguer J, Gómez-Talavera S, Rojas A, Salamanca J et al. · 2026
220
Does inflammation moderate the effect of vitamin D supplementation on depressive symptoms? Results of an interventional study in children and adolescents
Schlarbaum L, Jankovic N, Bühlmeier J, Hohoff E, Dankers R, Engler H et al. · 2026
221
Supplemental 25-Hydroxycholecalciferol Is More Effective than Cholecalciferol in Raising Serum 25-Hydroxyvitamin D Concentrations in Older Adults
Graeff-Armas LA, Bendik I, Kunz I, Schoop R, Hull S, Beck M · 2020
222
Combined effect of pulmonary rehabilitation and vitamin D supplementation on pulmonary function tests in asthma patients
Fatima A, Saxena R, Singh DK, Gupta S · 2026
223
Impact of vitamin D supplementation on disease severity and visual acuity in pediatric vernal keratoconjunctivitis (VKC) Vitamin D Supplementation in Vernal Keratoconjunctivitis
K S, V KC, S AK, Acharya P, S SB, K NP et al. · 2026
224
Efficacy of daily 4,000 International Units (IU) versus 6,000 IU of oral vitamin D3 in vitamin D deficient children with overweight and obesity: An open-label randomized controlled trial
Setia P, Seth A, Singh R, Malhotra RK, Singh P · 2025
225
Therapeutic high-dose vitamin D for vitamin D-deficient severe COVID-19 disease: randomized, double-blind, placebo-controlled study (SHADE-S)
Singh A, Rastogi A, Puri GD, Ganesh V, Naik NB, Kajal K et al. · 2024
226
Dietary supplements to reduce symptom severity and duration in people with SARS-CoV-2: a double-blind randomised controlled trial
Seely D, Legacy M, Conte E, Keates C, Psihogios A, Ramsay T et al. · 2023
227
Effect of cholecalciferol supplementation on CVD, inflammation and bone metabolism markers in CKD: results of feasibility phase of randomized double blind controlled placebo trial
Kamboj K, Manoharan K, Sharma S, Khera H, Shafiq N, Kohli HS et al. · 2024
228
The effect of vitamin D on renin-angiotensin system activation and blood pressure: a randomized control trial
McMullan CJ, Borgi L, Curhan GC, Fisher N, Forman JP · 2017
229
Efficacy of high-dose vs. low-dose vitamin D₃ supplementation in children with chronic tic disorders: a randomized controlled trial
Mohamed ZA, Bai M, Dong H, Xue Y, Jia F, Feng J · 2025
230
Effect of vitamin D as Nutrition Supplement on Patients with Prolonged Ventilation due to Ventilator Associated Pneumonia and Sepsis Followed Severe Traumatic Lung Contusion: A Randomized Controlled Trial
Allam MGIM, Alfeky AA, Abouelnour ASE, Hemaidah EGS, Adawy Z, Ramadan HSI et al. · 2026
231
Vitamin D Supplementation Improves Pathological Complete Response in Breast Cancer Patients Undergoing Neoadjuvant Chemotherapy: A Randomized Clinical Trial
Omodei MS, Chimicoviaki J, Buttros DAB, Almeida-Filho BS, Carvalho-Pessoa CP, Carvalho-Pessoa E et al. · 2025
232
The effectiveness of vitamin D supplementation in alleviating diabetes distress among patients with vitamin D deficiency at hospital putrajaya: an open label randomised controlled trial
Cheng WM, Hussein Z · 2025
233
Evaluation of efficacy of cholecalciferol and silymarin in improving lower urinary tract symptoms of benign prostatic hyperplasia: A double-blind, randomized, controlled trial
Valipour R, Narouie B, Momeni H, Radpour N, Torabinavid P, Momeni A et al. · 2024
234
Effectiveness of vitamin D2 supplementation on high-sensitivity C-reactive protein and other metabolic indices in menopausal Thai women: a randomized-controlled trial
Indhavivadhana S, Boonyachan W, Rattanachaiyanont M, Wongwananuruk T, Techatraisak K, Sa-Nga-Areekul N · 2022
235
The Clinico-Radiological Effect of Vitamin D in Treatment of Osteoarthritis of the Knee: A Randomized Control Trial
Singh S, Saraf A, Singh S, Kumar SK · 2025
236
Combined vitamin D and magnesium supplementation does not influence markers of bone turnover or glycemic control: A randomized controlled clinical trial
Dall RD, Cheung MM, Shewokis PA, Altasan A, Volpe SL, Amori R et al. · 2023
237
Exploring the synergistic effects of vitamin D and synbiotics on cytokines profile, and treatment response in breast cancer: a pilot randomized clinical trial
Tirgar A, Rezaei M, Ehsani M, Salmani Z, Rastegari A, Jafari E et al. · 2024
238
Potential Modulation of Inflammation and Physical Function by Combined Probiotics, Omega-3 Supplementation and Vitamin D Supplementation in Overweight/Obese Patients with Chronic Low-Grade Inflammation: A Randomized, Placebo-Controlled Trial
Kopp L, Schweinlin A, Tingö L, Hutchinson AN, Feit V, Jähnichen T et al. · 2023
239
"Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: A pilot randomized clinical study"
Entrenas Castillo M, Entrenas Costa LM, Vaquero Barrios JM, Alcalá Díaz JF, López Miranda J, Bouillon R et al. · 2020
240
Vitamin D deficiency and effect of treatment on seizure frequency and quality of life parameters in patients with drug-resistant epilepsy: A randomized clinical trial
Chassoux F, Navarro V, Quirins M, Laurent A, Gavaret M, Cousyn L et al. · 2024
241
Effects of cholecalciferol supplementation on depressive symptoms, C-peptide, serotonin, and neurotrophin-3 in type 2 diabetes mellitus: A double-blind, randomized, placebo-controlled trial
Putranto R, Setiati S, Nasrun MW, Witjaksono F, Immanuel S, Subekti I et al. · 2024
242
Effects of a multicomponent resistance-based exercise program with protein, vitamin D and calcium supplementation on cognition in men with prostate cancer treated with ADT: secondary analysis of a 12-month randomised controlled trial
Mundell NL, Owen PJ, Dalla Via J, Macpherson H, Daly RM, Livingston PM et al. · 2022
243
Effect of a combination of genistein, polyunsaturated fatty acids and vitamins D3 and K1 on bone mineral density in postmenopausal women: a randomized, placebo-controlled, double-blind pilot study
Lappe J, Kunz I, Bendik I, Prudence K, Weber P, Recker R et al. · 2013
244
Effectiveness of SOLIUS UVB Light System in Enhancing Serum 25-Hydroxyvitamin D Concentrations: A Randomized Controlled Trial
Shirvani A, Holick MF · 2025
245
Is Vitamin D Supplementation Effective in Prevention of Recurrent Urinary Tract Infections in the Pediatrics? A Randomized Triple-Masked Controlled Trial
Merrikhi A, Ziaei E, Shahsanai A, Kelishadi R, Maghami-Mehr A · 2018
246
Inflammation (IL-1β) Modifies the Effect of Vitamin D and Omega-3 Long Chain Polyunsaturated Fatty Acids on Core Symptoms of Autism Spectrum Disorder-An Exploratory Pilot Study‡
Mazahery H, Conlon CA, Beck KL, Mugridge O, Kruger MC, Stonehouse W et al. · 2020
247
Adjunctive vitamin D supplementation in women receiving dienogest therapy for endometriosis: a randomized controlled trial
Shabani F, Hajizadeh K, Hesami M, Shaseb E, Rahmani V, Nasirkandy MP et al. · 2026
248
Alcohol use disorder and muscle weakness: Original study of the effect of vitamin D supplementation in ambulatory participants with alcohol use disorder
Wijnia JW, Wierdsma AI, Oudman E, Oey MJ, Groen J, Beuman C et al. · 2024
249
The effect of vitamin D and magnesium supplementation on the mental health status of attention-deficit hyperactive children: a randomized controlled trial
Hemamy M, Pahlavani N, Amanollahi A, Islam SMS, McVicar J, Askari G et al. · 2021
250
Effect of Vitamin D and Magnesium Supplementation on Behavior Problems in Children with Attention-Deficit Hyperactivity Disorder
Hemamy M, Heidari-Beni M, Askari G, Karahmadi M, Maracy M · 2020
251
Positive Effect of Vitamin D and Magnesium Supplementation on Mental health Status of Attention-Deficit Hyperactive Children; A Randomized Double blind Controlled Clinical Trial
Hemamy M, Pahlavani N, Askari G, Malekahmadi M · 2020
252
Effect of Monthly and Bi-Monthly 50,000 International Units (IU) Maintenance Therapy With Vitamin D3 on Serum Level of 25-Hydroxyvitamin D in Adults: A Randomized Controlled Trial
AlAteeq MA, AlShail A, AlZahrani A, AlNafisah O, Masuadi E, Alshahrani A · 2021
253
Effect of two vitamin D repletion protocols on 24-h urine calcium in patients with recurrent calcium kidney stones and vitamin D deficiency: a randomized clinical trial
Sardari Masihi L, Borumandnia N, Taheri M, Basiri A, Imani H, Jalali S et al. · 2023
254
Does vitamin D supplementation improve bone health, body composition and physical performance beyond endurance exercise in patients with type 2 diabetes: A secondary analysis of randomized controlled trial
Sun X, Xiao W, Li Z, Zhou S, Dong M, Huang C et al. · 2022
255
Effect of vitamin D supplementation on clinical outcomes of patients with Parkinson disease: A randomized controlled study
Anamnart C, Kitjarak R · 2026
256
Combined Effects of Physiotherapy and Vitamin D Supplementation on Pain, Disability, and IL-6 Expression in Chronic Low Back Pain: A Randomized Controlled Trial
Albalwi AA, Al Amer HS, Mir R, Mohamed SHP, Javid J, Mir MM et al. · 2026
257
Combined oral supplementation with magnesium plus vitamin D alleviates mild to moderate depressive symptoms related to long-COVID: an open-label randomized, controlled clinical trial
Rodríguez-Morán M, Guerrero-Romero F, Barragán-Zuñiga J, Gamboa-Gómez CI, Weyman-Vela Y, Arce-Quiñones M et al. · 2024
258
Comparison between Acupuncture and Nutraceutical Treatment with Migratens® in Patients with Fibromyalgia Syndrome: A Prospective Randomized Clinical Trial
Schweiger V, Secchettin E, Castellani C, Martini A, Mazzocchi E, Picelli A et al. · 2020
259
Dose-response effects of supplementation with calcifediol on serum 25-hydroxyvitamin D status and its metabolites: A randomized controlled trial in older adults
Vaes AMM, Tieland M, de Regt MF, Wittwer J, van Loon LJC, de Groot LCPGM · 2018
260
One year B-vitamins increases serum and whole blood folate forms and lowers plasma homocysteine in older Germans
Kirsch SH, Herrmann W, Kruse V, Eckert R, Gräber S, Geisel J et al. · 2015
261
The Effect of Vitamin D Supplementation on Ankle-brachial Index in Patients with Type 2 Diabetes: A Randomized Clinical Trial
Yekefallah L, Jalalpour A, Aghakhanbeigi F, Namdar P, Mafi MH · 2025
262
The immune cell transcriptome is modulated by vitamin D3 supplementation in people with a first demyelinating event participating in a randomized placebo-controlled trial
Yeh WZ, Gresle M, Lea R, Taylor B, Lucas RM, Ponsonby AL et al. · 2024
263
Combined Effects of Combined Resistance Exercise and Vitamin D Supplementation on Cardiometabolic Profiles and Functional Capacities in Elderly Women with Type 2 Diabetes
Kim HJ, Yoo DS, Lee MG · 2026
264
Synergistic Effects of Combined Resistance Exercise and Vitamin D Supplementation on Cardiometabolic Profiles and Functional Capacities in Elderly Women with Type 2 Diabetes
Kim H, Yoo D, Lee M · 2026
265
Effect of Medically Supervised Prolonged Fasting Therapy on Vitamin D, B12, Body Weight, Body Mass Index, Vitality and Quality of Life: A Randomized Control Trial
Tewani GR, Silwal K, Sharma G, Yadav D, Siddiqui A, Kriplani S et al. · 2022
266
Preventive treatment with alendronate of loss of bone mineral density in acute traumatic spinal cord injury. Randomized controlled clinical trial
Fernández Dorado MT, Díaz Merino MDS, García Marco D, Cuena Boy R, Blanco Samper B, Martínez Dhier L et al. · 2022
267
Effect of Vitamin D Supplementation Regimens on Fracture Healing and Serum Biomarker Profile in Long-Bone Fractures: A Prospective Randomized Study
Selvaraj NV, Alsaifi MS, Singh SK, Kamra P, Vaithinathan P, Alsalahi RA · 2026
268
Efficacy of two calcifediol supplementation regimens in older adults post-hip fracture surgery. A clinical trial
Cuadra-Llopart L, Salvà Casanovas A, Cerdà Mas G, Jovell-Fernández E · 2026
269
Positive Effects of Vitamin D Supplementation in Patients Hospitalized for COVID-19: A Randomized, Double-Blind, Placebo-Controlled Trial
De Niet S, Trémège M, Coffiner M, Rousseau AF, Calmes D, Frix AN et al. · 2022
270
Isoflavones, calcium, vitamin D and inulin improve quality of life, sexual function, body composition and metabolic parameters in menopausal women: result from a prospective, randomized, placebo-controlled, parallel-group study
Vitale SG, Caruso S, Rapisarda AMC, Cianci S, Cianci A · 2018
271
An 8-Week Vitamin D3-Fortified Fruit Drink Supplementation Increases Serum Ferritin Concentration: A Randomized Controlled Trial in Malaysian Women With Low Iron Stores
Suhaimi NA, Loh SP, Ab Manan N, Zalbahar N, Mohamad Alwi MN, Ahmad Fuzi SF · 2024
272
Role of vitamin D supplement adjunct to topical benzoyl peroxide in acne: a randomized double-blinded controlled study
Ruikchuchit T, Juntongjin P · 2024
273
No discernible effect of vitamin D supplementation on secondary outcomes in chronic spinal cord injury: Findings from a randomized controlled trial
Hertig-Godeschalk A, Flueck JL, Scheel-Sailer A, Perret C, Brinkhof MWG · 2025
274
Efficacy of Vitamin D3 Supplementation in Elevating Circulating 25(OH)D Concentration in Individuals With Chronic Spinal Cord Injury (VitD-SCI): Evidence From a Randomized, Double-Blind, Placebo-Controlled Trial
Hertig-Godeschalk A, Brinkhof MWG, Perret C, Scheel-Sailer A, Flueck JL · 2025
275
Does Consuming Fresh Ultraviolet Light-Exposed Mushrooms Offset the Seasonal Decline in Serum Total 25OHD in Adults Classified as Overweight and Class I Obese? Results from a Randomized Controlled Trial
Comboni LM, Glover ES, Napolitano SC, Fleet JC, Foti D, Olson MR et al. · 2026
276
Effect of vitamin D supplementation on metabolic syndrome and atherosclerosis biomarkers in epilepsy: a randomized controlled trial
Handayani S, Hafy Z, Octaviana F, Ali Z, Parisa N, Budikayanti A et al. · 2026
277
Comparative evaluation of the effects of diclofenac sodium and vitamin D supplementation on symptoms in individuals with myofascial pain and vitamin D deficiency: a randomized controlled clinical trial
Kahraman NH, Tunç SK · 2025
278
Effect of supplementation with vitamins D3 and K2 on undercarboxylated osteocalcin and insulin serum levels in patients with type 2 diabetes mellitus: a randomized, double-blind, clinical trial
Aguayo-Ruiz JI, García-Cobián TA, Pascoe-González S, Sánchez-Enríquez S, Llamas-Covarrubias IM, García-Iglesias T et al. · 2020
279
Ergocalciferol and microcirculatory function in chronic kidney disease and concomitant vitamin d deficiency: an exploratory, double blind, randomised controlled trial
Dreyer G, Tucker AT, Harwood SM, Pearse RM, Raftery MJ, Yaqoob MM · 2014
280
Ergocalciferol in New-onset Type 1 Diabetes: A Randomized Controlled Trial
Nwosu BU, Parajuli S, Jasmin G, Fleshman J, Sharma RB, Alonso LC et al. · 2022
281
Multistrain Probiotics Plus Vitamin D Improve Gut Barrier Function and Gut Microbiota Composition in Irritable Bowel Syndrome Without Constipation: Results from a Double-Blind, Randomized, Placebo-Controlled Trial
Laterza L, Cremon C, Coppola G, Settanni CR, Maresca R, Strazzeri M et al. · 2025
282
A Comparison and Safety Evaluation of Micellar versus Standard Vitamin D3 Oral Supplementation in a Randomized, Double-Blind Human Pilot Study
Solnier J, Chang C, Zhang Y, Kuo YC, Du M, Roh YS et al. · 2024
283
High-Dose Vitamin D and Early Chronic Pancreatitis-Related Changes After Acute Pancreatitis: A Randomized Dose Controlled Trial
Parhiala M, Aronen A, Ukkonen M, Haukijärvi E, Pappinen P, Rinta-Kiikka I et al. · 2026
284
The prognosis of patients with myocardial infarction after light therapy: A preliminary study
Chin WC, Huang YS, Wu LS, Lee KT, Ho CT, Lin C et al. · 2025
285
Vitamin D3 Supplementation Enhances Symptom Relief and Modulates Microbiome and Immune Responses in Pediatric Post-Acute Sequelae of COVID-19: A Randomized Controlled Trial
Chen P, Liu T, Chuang Y, Hsu Y, Chen Y, Lin C et al. · 2026
286
Effect of a glucosamine-based combination supplement containing chondroitin sulfate and antioxidant micronutrients in subjects with symptomatic knee osteoarthritis: A pilot study
Nakasone Y, Watabe K, Watanabe K, Tomonaga A, Nagaoka I, Yamamoto T et al. · 2011
287
[Therapeutic effect of vitamin D supplementation in mexican patients with allergic rhinitis]
Rivero-Yeverino D, Payan-Diaz JH, López-García AI, Papaqui-Tapia JS, Caballero-López CG, Ríos-López JJ et al. · 2024
288
Effects of high- vs low-dose native vitamin D on albuminuria and the renin-angiotensin-aldosterone system: a randomized pilot study
Krummel T, Ingwiller M, Keller N, Prinz E, Charlin E, Bazin D et al. · 2022
289
Concurrent effects of high-intensity interval training and vitamin D supplementation on bone metabolism among women diagnosed with osteoporosis: a randomized controlled trial
Alghadir AH, Gabr SA, Iqbal A · 2025
290
Effects of Macuprev® Supplementation in Age-Related Macular Degeneration: A Double-Blind Randomized Morpho-Functional Study Along 6 Months of Follow-Up
Parravano M, Tedeschi M, Manca D, Costanzo E, Di Renzo A, Giorno P et al. · 2019
291
Effect of Treating Vitamin D Deficiency in Uncontrolled Type 2 Diabetes: A Randomized, Placebo-Controlled Study
Lo MC, Abushamat L, Mramba LK · 2019
292
PROTECTIVE-D-a feasibility randomised controlled trial examining the effect of a positive mood intervention and vitamin D supplementation on the immunological responses to influenza vaccination in older adults
Royal S, Ayling K, Hopkins G, Fairclough LC, Vedhara K · 2026
293
High-dose vs standard-dose vitamin D and sleep in early childhood: A randomized clinical trial
Seppälä V, Holmlund-Suila E, Hauta-Alus H, Sandboge S, Kajantie E, Rosendahl J et al. · 2026
294
Early life vitamin D and neurocognitive abilities at age 6-8 years: a randomized clinical trial and observational analysis
Seppälä V, Sandboge S, Holmlund-Suila E, Hauta-Alus H, Lintula S, Kajantie E et al. · 2026
295
A Combination of Whey Protein and Vitamin D Reduces Sarcopenia in Patients with Chronic Obstructive Pulmonary Disease. A Randomized Controlled Trial
Qaisar R, Khan IU, Ahmad F, Karim A · 2026
296
Investigation of the Effect of Vitamin D Supplementation on Apical Lesion Healing Rate: Prospective, Randomised Clinical Trial
Maraş E, Aricioğlu B, Beyazal Polat H, Arpa M, Günaçar DN, Köse TE · 2026
297
Vitamin D and calcium prevent bone loss in vitamin D-deficient chronic hepatitis B patients treated with tenofovir disoproxil fumarate: A randomized controlled trial
Atthakitmongkol T, Chotiyaputta W, Lertwattanarak R, Sritippayawan S, Bandidniyamanon W, Tanwandee T · 2026
298
High-dose Vitamin D3 supplementation and glycaemic control in adult males with Type 2 diabetes: a randomised placebo-controlled trial
Nasr MH, Abdulrasool Hassan B, Othman N, Karuppannan M, Hussain SM, Abdulaziz NB et al. · 2026
299
Effects of vitamin D supplementation on metabolic factors, serum omentin-1, and anthropometric indices in middle-aged women with prediabetes: a double-blind randomized controlled trial
Molani-Gol R, Rafraf M, Asghari Jafarabadi M, Aftabi-Yousefabad S · 2025
300
Effect of vitamin D supplementation on skeletal muscle function and quality of life in patients with chronic intestinal failure: a randomized controlled trial : Clean version
Gao X, Liu S, Zhang Y, Xia Y, Liu S, Qi X et al. · 2025
301
Impact of high-dose vitamin D supplementation initiated shortly after diagnosis on residual beta cell function and partial remission rates in children with type 1 diabetes
Nallapu C, Dayal D, Sachdeva N, Kumar M, Attri SV · 2025
302
Daily versus fortnightly oral vitamin D3 in treatment of symptomatic vitamin D deficiency in children aged 1-10 years: An open labelled randomized controlled trial
Mondal KAP, Singh P, Singh R, Malhotra RK, Seth A · 2024
303
Correlation Between Reduced IL-1β Levels in Acne Lesions and the Decrease in Acne Inflammatory Lesions Following Topical Vitamin D Administration: A Double-Blind Randomized Controlled Trial
Dahlan NH, Sitohang IBS, Indriatmi W, Wibowo H, Enggy LE · 2024
304
Safety and Efficacy of Topical Vitamin D in the Management of Dry Eye Disease Associated With Meibomian Gland Dysfunction: A Placebo-Controlled Double-Blind Randomized Controlled Trial
Hassanpour K, Langari F, Akbarzadeh AR, Kanavi MR, Barani M, Kheiri B et al. · 2024
305
Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial
Hahn J, Cook NR, Alexander EK, Friedman S, Walter J, Bubes V et al. · 2022
306
Effect of Cholecalciferol Supplementation on the Clinical Features and Inflammatory Markers in Hospitalized COVID-19 Patients: A Randomized, Open-Label, Single-Center Study
Karonova TL, Golovatyuk KA, Kudryavtsev IV, Chernikova AT, Mikhaylova AA, Aquino AD et al. · 2022
307
Efficacy of plain cholecalciferol versus ergocalciferol in raising serum vitamin D level in Thai female healthcare workers
Amphansap T, Therdyothin A, Stitkitti N, Nitiwarangkul L, Phiphobmongkol V · 2022
308
Standard and high dose ergocalciferol regimens for treatment of hypovitaminosis D in epileptic children and adolescents
Vichutavate S, Suwanpakdee P, Likasitthananon N, Numbenjapon N, Nabangchang C, Phatarakijnirund V · 2022
309
Efficacy of high versus conventional dose of ergocalciferol supplementation on serum 25-hydroxyvitamin D and interleukin-6 levels among hemodialysis patients with vitamin D deficiency: A multicenter, randomized, controlled study
Nata N, Siricheepchaiyan W, Supasyndh O, Satirapoj B · 2022
310
Effect of vitamin D supplementation in patients with chronic hepatitis C after direct-acting antiviral treatment: a randomized, double-blind, placebo-controlled trial
Sriphoosanaphan S, Thanapirom K, Kerr SJ, Suksawatamnuay S, Thaimai P, Sittisomwong S et al. · 2021
311
Positive effect of a new supplementation of vitamin D3 with myo-inositol, folic acid and melatonin on IVF outcomes: a prospective randomized and controlled pilot study
Bezerra Espinola MS, Bilotta G, Aragona C · 2021
312
Musculoskeletal Responses to Exercise Plus Nutrition in Men with Prostate Cancer on Androgen Deprivation: A 12-Month RCT
Dalla Via J, Owen PJ, Daly RM, Mundell NL, Livingston PM, Rantalainen T et al. · 2021
313
Effect of Vitamin D on Endothelial Function: A Randomized, Double-Blind, Placebo-Controlled Trial
Borgi L, McMullan C, Wohlhueter A, Curhan GC, Fisher ND, Forman JP · 2017
314
Nutraceutical intervention improves older adults' cognitive functioning
Small BJ, Rawson KS, Martin C, Eisel SL, Sanberg CD, McEvoy CL et al. · 2014
315
[Effect of milk product with soy isoflavones on quality of life and bone metabolism in postmenopausal Spanish women: randomized trial]
García-Martín A, Quesada Charneco M, Alvárez Guisado A, Jiménez Moleón JJ, Fonollá Joya J, Muñoz-Torres M · 2012
316
Soy isoflavones have a favorable effect on bone loss in Chinese postmenopausal women with lower bone mass: a double-blind, randomized, controlled trial
Chen YM, Ho SC, Lam SS, Ho SS, Woo JL · 2003
317
Clinical and Immunological Effects of Systemic Vitamin D Supplementation in Vitamin D-Deficient Dry Eye Disease: A Prospective Comparative Study
Aslanova V, Huseynli S · 2026
318
Ultra-High Dose Vitamin D in Pediatric Hematopoietic Stem Cell Transplantation: A Nonrandomized Controlled Trial
Bhandari R, Aguayo-Hiraldo P, Malvar J, Cheng K, Sacapano A, Abdel-Azim H et al. · 2021
319
Effectiveness of intralesional vitamin D3 injection in the treatment of common warts: Single-blinded placebo-controlled study
Kareem IMA, Ibrahim IM, Mohammed SFF, Ahmed AA · 2019
320
Effect of vitamin D supplementation on cardiovascular outcomes: randomized trials revisited
Wang Y, Sha S, Gwenzi T, Schöttker B, Brenner H · 2026
321
Clinically Sufficient Vitamin D Levels With Survival and Cardiovascular Outcomes in a Prospective Cohort of 3,995 Individuals Diagnosed With Invasive Breast Cancer
Yao S, Chua AV, Sheng H, Zimbalist A, Hill JW, Roh JM et al. · 2026
322
Inappropriate vitamin D supplementation among multimorbid older patients: a multicountry analysis
Moutzouri E, Beglinger S, Feller M, Eichenberger A, Dalleur O, Knol W et al. · 2025
323
Vitamin D Deficiency During Pregnancy Is Associated With Greater LDL-C Increase, Elevated β-Hydroxybutyrate and Altered Neonatal Metabolic Markers-A Secondary, Pooled Analysis of the Randomized, Controlled Vitamin D and Lifestyle for Gestational Diabetes Prevention Trial (DALI)
Harreiter J, Gisinger T, Mendoza LC, Simmons D, Desoye G, Devlieger R et al. · 2026
324
Baseline engagement with healthy lifestyles and their associations with health outcomes in people with multiple sclerosis enrolled in an online multimodal lifestyle course
Yu M, Neate S, Nag N, Bevens W, Jelinek G, Simpson-Yap S et al. · 2024
325
Periconception Maternal-Serum Vitamin D, Vaginal Bleeding, and Subchorionic Hemorrhage in Early Pregnancy
Alkhalaf ZM, Mumford SL, Schisterman EF, Silver RM, Thoma ME · 2026
326
Calcifediol Treatment and Hospital Mortality Due to COVID-19: A Cohort Study
Alcala-Diaz JF, Limia-Perez L, Gomez-Huelgas R, Martin-Escalante MD, Cortes-Rodriguez B, Zambrana-Garcia JL et al. · 2021
327
Exploring associations between maternal vitamin D-binding protein, vitamin D, and offspring asthma/recurrent wheeze
Boyd SS, Hecker J, Mirzakhani H, DeMeo DL, Weiss ST, Halu A · 2026
328
Circulating Piwi-Interacting RNAs Associate With Childhood Asthma ICS Response With Vitamin D Effect Modification
Li J, Hong X, Chi M, Kho AT, Zhu Z, Zhang H et al. · 2026
329
Metabolic phenotypes and vitamin D response in the critically ill: A metabolomic cohort study
Kobayashi H, Amrein K, Mahmoud SH, Lasky-Su JA, Christopher KB · 2024
330
Vitamin D [25(OH)D] metabolites and epimers in obese subject: Interaction and correlations with adverse metabolic health risk factors
Gariballa S, Shah I, Yasin J, Alessa A · 2022
331
Sociodemographic factors affecting perceived stress during pregnancy and the association with immune-mediator concentrations
McLeod C, Ebeling MD, Baatz JE, Shary JR, Mulligan JR, Wagner CL · 2022
332
Real-World Assessment: Clinical Effectiveness and Safety of Extended-Release Calcifediol
Fadda G, Germain MJ, Broumand V, Nguyen A, McGarvey N, Gitlin M et al. · 2021
333
Does Vitamin D Supplementation Slow Brain Volume Loss in Multiple Sclerosis? A 4-Year Observational Study
Galus W, Winder M, Owczarek AJ, Walawska-Hrycek A, Rzepka M, Kaczmarczyk A et al. · 2025
334
Serum vitamin D level and its association with vertigo frequency and severity in Meniere disease
Khajedaluee AR, Rajati M, Tabatabaei D, Jafarzadeh S, Tabesh H, Afzalzadeh MR et al. · 2026
335
Effect of vitamin D treatment in ANCA-associated vasculitis: results from an exploratory perspective, pragmatic, non-randomised study
Basti A, Zgaga L, Doubelt I, Soowamber M, Pagnoux C · 2026
336
Mathematical analysis of Córdoba calcifediol trial suggests strong role for Vitamin D in reducing ICU admissions of hospitalized COVID-19 patients
Jungreis I, Kellis M · 2020
337
Mini-review. Vitamin D for the prevention of type 2 diabetes: Evidence and implications
Amrein K, Kim SH, Brath H, Fasching P, Pittas AG · 2026
338
Vitamin D Supplementation in Critically Ill-Narrative Review
Saric L, Domazet Bugarin J, Dosenovic S · 2024
339
Guidance for high-dose vitamin D supplementation for prolonging the honeymoon phase in children and adolescents with new-onset type 1 diabetes
Nwosu BU · 2022

Every statement on this page carries its evidence tier — proven, plausible or hypothesis — and leads to the original work. The decision in the individual case rests with the practitioner; we provide the connections.