Rosmarinic Acid

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1. What Rosemary Acid Is

Rosemary acid (chemical name: O-caffeoyl-3,4-dihydroxyphenyllactic acid) is an ester of caffeic acid and a secondary plant compound from the group of hydroxycinnamic acid derivatives. It occurs in numerous Lamiaceae species, including rosemary (Rosmarinus officinalis), lemon balm (Melissa officinalis), sage and mint. In plants, it serves as an antioxidant and defence compound against pathogens. For research, it is relevant as a marker compound in extracts, as it can be measured in a standardised way and correlates with other polyphenols. Industrially, it is extracted from plant raw materials, with Melissa officinalis being the most common source for controlled studies.

Crucial for the study evidence is the bioavailability and metabolism of rosemary acid: After oral intake, it is partially hydrolysed in the intestine, with caffeic acid and 3,4-dihydroxyphenyllactic acid emerging as main metabolites. These metabolites reach higher plasma concentrations than the parent compound and are presumably responsible for systemic effects. Most human studies use standardised extracts with a defined rosemary acid content, as the pure substance is poorly water-soluble. Pharmacokinetics show rapid absorption (peak values after 1–2 hours) and a half-life of 4–6 hours, which supports daily intake.

2. What the Studies Show in Detail

The key human studies and most important reviews — grouped by application area, with population, duration, preparation, measurement parameters and results as reported in the original works. Numbers are included only where the study provides them.

Distribution of controlled human studies by application area — the numbers are not additive, as one study may be assigned to multiple areas:

Safety and Tolerability

Proven Rosmarinic acid in the form of a Melissa officinalis extract (500 mg rosmarinic acid per dose) was tested for safety and pharmacokinetics in a randomised, controlled study involving 11 healthy volunteers 1. In the fasting state, serum rosmarinic acid concentration reached a maximum of 162.20 nmol/L after 1 hour, with an area under the curve (AUC) of 832.13 nmol·h/L. Food intake delayed absorption and increased AUC without affecting tolerability. Laboratory parameters (liver, kidney function, blood count) remained unchanged, and no adverse events occurred. The study confirms the safety of a single dose of 500 mg rosmarinic acid from Melissa officinalis in healthy adults.

Proven A 90-day, placebo-controlled study with an aqueous Mentha spicata extract (standardised to rosmarinic acid) at 600 and 900 mg/day showed no impact on hormone levels (FSH, LH, TSH), vital signs or haematological/biochemical markers in healthy adults with age-related memory impairment 19. No serious adverse events were reported, and observed side effects were not attributable to the extract. The results support the tolerability of long-term intake of rosmarinic acid-containing extracts at these doses.

Missing: Long-term studies on the safety of rosmarinic acid over several years, particularly in vulnerable groups such as pregnant women or patients with chronic diseases.

Cognition and Psyche

Evidence: A 24-week, randomised, placebo-controlled double-blind study in 23 patients with mild Alzheimer’s dementia investigated the effects of Melissa officinalis extract (500 mg rosmarinic acid/day) 2. The primary endpoint was safety, which was confirmed: no differences in vital signs or physical examinations between the verum and placebo groups. Secondary outcomes showed a significant improvement in the Neuropsychiatric Inventory Questionnaire (NPI-Q) by 0.5 points in the verum group, while the placebo group worsened by 0.7 points (p = 0.012). Cognitive measures (e.g., MMSE) remained unchanged, as did biomarkers. The study suggests that rosmarinic acid may stabilise neuropsychiatric symptoms in mild Alzheimer’s dementia.

Evidence: In a 96-week, randomised, placebo-controlled study involving 323 older adults without dementia (subjective or mild cognitive impairment), Melissa officinalis extract (500 mg rosmarinic acid/day) was tested 4. The primary endpoint was the Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog), which showed no significant differences between groups. However, a subgroup analysis in participants without hypertension revealed stabilisation of the Clinical Dementia Rating Sum of Boxes (CDR-SB) in the verum group (-0.085 points) compared to deterioration in the placebo group (+0.006 points). The results suggest potential cognitive benefits in specific populations but require further confirmation.

Evidence: An 8-week, randomised, placebo-controlled study in patients with major depression examined the effects of rosemary capsules (containing rosmarinic acid among other compounds) as adjunctive therapy. After 8 weeks, the verum group showed a significant reduction in anxiety scores (Hospital Anxiety and Depression Scale, HADS-A) and depression scores (Beck Depression Inventory-II) compared to the placebo group. A positive side effect was an improvement in memory. The study suggests that rosemary extracts may contribute to alleviating depressive and anxiety symptoms, though the specific role of rosmarinic acid remains to be clarified.

Evidence: A 30-day, randomised, placebo-controlled study of a polyphenol-rich plant extract (including rosmarinic acid among other compounds) in 89 participants with subclinical sleep disorders showed significant improvements in subjective sleep quality (p = 0.008) and a reduction in insomnia severity (Insomnia Severity Index, ISI; p = 0.044) in the verum group 20. No impairments in neurocognitive functions were observed; instead, improvements were seen in vigilance, working memory, and risk assessment. The study supports the assumption that polyphenol-rich extracts may positively influence sleep quality and cognitive functions, though the contribution of individual compounds, including rosmarinic acid, is not isolated.

Evidence: A prospective, placebo-controlled cross-over study with a highly standardised Melissa officinalis phytosome (containing 500 mg rosmarinic acid/day) in participants with sleep disorders showed a significant reduction in ISI scores by 2.9 points (p = 0.003) in the verum group after 30 days 5. The duration of the slow-wave sleep phase (deep sleep) increased by 15%, while the REM phase decreased by 10%. 87% of participants reported improved sleep quality (vs. 30% in the placebo group). The results indicate that Melissa officinalis extracts may influence sleep architecture and quality, though the specific role of rosmarinic acid remains to be determined.

Hypothesis The observed effects on neuropsychiatric symptoms, sleep, and mood may be due to rosmarinic acid’s modulation of neurotransmitter systems such as GABA, serotonin, and acetylcholine. Additionally, its antioxidant and anti-inflammatory properties may mediate neuroprotective effects, particularly in neurodegenerative processes.

Missing: Long-term studies on the cognitive effects of rosmarinic acid in healthy older adults, as well as targeted investigations into underlying neurobiological mechanisms (e.g., modulation of neurotransmitters or inflammatory markers).

Bones and Joints

Primary endpoints were pain, stiffness, and physical function (measured using the Western Ontario and McMaster Universities Osteoarthritis Index, WOMAC). In the verum group, WOMAC pain scores decreased significantly, while the placebo group showed no change. Both groups experienced a reduction in WOMAC stiffness and physical impairment scores. Quality of life (SF-36, Bodily Pain Index) improved only in the verum group, though without a significant difference compared to the placebo group. The study provides preliminary evidence that rosmarinic acid-containing extracts may influence surrogate endpoints related to symptoms in knee osteoarthritis, though clinical relevance remains to be confirmed.

Missing: Studies on the effects of rosmarinic acid on structural joint changes (e.g., cartilage degradation) and investigations into potential synergistic effects with established therapies such as NSAIDs or physiotherapy.

Oxidative Stress

Evidence: A 9-week, randomised, placebo-controlled phase II study in 110 cancer patients (stage II–IV) with chemotherapy-induced fatigue examined the effects of Nuvastatic (1000 mg, 3× daily; standardised rosmarinic acid-rich extract) 7. Primary endpoints were fatigue scores (Brief Fatigue Inventory, BFI; Visual Analog Scale for Fatigue, VAS-F). The verum group showed a significant reduction in BFI scores (F(1.4; 147) = 16.554; p < 0.001; partial η² = 0.333) compared to the placebo group. Secondary outcomes included a decrease in urinary F2-isoprostanes (a biomarker for oxidative stress), indicating a potential antioxidant effect of rosmarinic acid. The study showed that rosmarinic acid may influence fatigue and oxidative stress biomarkers in cancer patients.

Preclinical evidence: An in-vitro study in prostate cancer cells (PC3, LNCaP) and healthy fibroblasts (HFF-1) investigated the effects of a nanocomplex composed of rosmarinic acid, selenium-doped titanium oxide, and graphene oxide 9. The complex exhibited significantly higher cytotoxicity against cancer cells (IC50 values after 24/48 h were markedly lower than for pure rosmarinic acid) and induced apoptosis by increasing reactive oxygen species (ROS) and modulating gene expression (Bcl-2↓, Bax↑). The results suggest potential oncological applications for rosmarinic acid in nanotechnologically optimised formulations, though these preclinical findings require clinical validation.

Missing: Clinical studies on the antioxidant effects of rosmarinic acid in other conditions involving oxidative stress (e.g., cardiovascular diseases, diabetes) and investigations into optimal dosing and formulations for maximum bioavailability.

Inflammatory Processes

Evidence: A systematic review and meta-analysis of 9 randomised controlled trials (n = 966) examined the effects of Prunella Oral Liquid (an extract of Prunella vulgaris containing rosmarinic acid) in combination with standard Western therapy in patients with Graves’ disease 18. The combination therapy led to a significant reduction in free thyroid hormones FT3 (SMD = -0.94; 95% CI: -1.63 to -0.26) and FT4 (SMD = -0.87; 95% CI: -1.55 to -0.19), as well as an increase in TSH (SMD = 0.79; 95% CI: 0.31 to 1.27) compared to standard therapy alone. Additionally, TRAb levels (thyroid-stimulating hormone receptor antibodies) decreased significantly. The study provides evidence for the potential anti-inflammatory and immunomodulatory effects of the Prunella vulgaris extract in combination with standard therapy in autoimmune thyroid diseases.

Preclinical evidence: An in-vitro study in BV2 microglial cells investigated the effects of a Melissa officinalis phytocomplex (high in rosmarinic acid) on neuroinflammation induced by high glucose concentrations 11. After 48 hours of exposure to high glucose levels, microglial activation (CD11b↑ by 187%), NF-κB pathway activation (↑ 179%), increased expression of iNOS (↑ 225%) and IL-6 (↑ 173%), and enhanced phosphorylation of ERK1/2 (↑ 180%) were observed. Pretreatment with the phytocomplex prevented these inflammatory changes. The study suggests a preclinical modulatory effect of the phytocomplex on neuroinflammatory processes, though human relevance remains to be investigated.

Hypothesis The anti-inflammatory effects of rosmarinic acid may involve multiple mechanisms, including inhibition of the NF-κB pathway and modulation of cytokines (e.g., IL-6, TNF-α). These effects could be relevant not only in autoimmune diseases but also in chronic inflammatory conditions such as rheumatoid arthritis or inflammatory bowel disease.

Missing: Clinical studies on the anti-inflammatory effects of rosmarinic acid in chronic inflammatory diseases and investigations into potential synergistic effects with established anti-inflammatory therapies.

Viral Infections

Preclinical evidence: An in-vitro study identified rosmarinic acid as an inhibitor of the interaction between the ε-RNA element of the hepatitis B virus (HBV) and the viral polymerase, a critical step in the replication cycle 8. Rosmarinic acid reduced HBV DNA levels in primary human hepatocytes from a humanised mouse liver without cytotoxic effects. Combination with lamivudine (a nucleoside analogue) showed additive effects, suggesting different mechanisms of action. Structural analyses of 25 rosmarinic acid derivatives indicated that the "two phenolic hydroxyl groups at both ends" and the "caffeic acid-lactic acid structure" are crucial for antiviral activity. These preclinical findings require clinical validation.

Preclinical evidence: A network pharmacology analysis and in-vitro validation examined the antiviral effects of rosmarinic acid against Chikungunya virus (CHIKV) 10. The analysis identified the IL-17 signalling pathway as a central mechanism in CHIKV pathogenesis. Rosmarinic acid (60 µM) significantly improved the survival rate of infected 293T cells and modulated 30 target proteins, nearly half of which were associated with the IL-17 pathway. Molecular docking studies confirmed stable binding to 10 of these target proteins. The results suggest a preclinical antiviral potential of rosmarinic acid through modulation of host immune responses.

Hypothesis The antiviral effects of rosmarinic acid may result from a combination of direct inhibition of viral enzymes (e.g., polymerases) and indirect modulation of host immune responses (e.g., IL-17 pathway). This could make rosmarinic acid a promising candidate for the development of broad-spectrum antiviral therapies, particularly against viruses with limited treatment options.

What is missing: Clinical studies on the antiviral effect of rosmarinic acid in human infections (e.g., HBV, CHIKV), as well as investigations into optimal dosages and formulations for therapeutic application.

Oncology

Preclinically demonstrated: An in-vitro and in-vivo study examined the effect of Echium amoenum extract (EAEC) and rosmarinic acid on gastric cancer cells (AGS cell line) 12. EAEC and rosmarinic acid inhibited cell growth by inducing apoptosis (mediated via caspases) and suppressed metastasis by modulating biomarkers of epithelial-mesenchymal transition (EMT). Additionally, the STAT3, AKT, and ERK1/2 signaling pathways were inactivated. In a preclinical model, rosmarinic acid significantly reduced tumour growth. The results suggest that rosmarinic acid may exert preclinical antiproliferative and antimetastatic effects in gastric cancer.

Hypothesis The oncological effects of rosmarinic acid may be based on a combination of antioxidant activity, inhibition of inflammatory pathways (e.g., NF-κB), and direct modulation of signal transduction pathways (e.g., STAT3, AKT) 21. These mechanisms could also be relevant in other cancer types, particularly those with high metastatic potential or therapy resistance.

What is missing: Clinical studies on the oncological effect of rosmarinic acid in cancer patients, particularly in combination with established therapies such as chemotherapy or immunotherapy, as well as investigations into possible resistance mechanisms.

Overall Picture

Rosmarinic acid demonstrates broad therapeutic potential, with preclinical and early clinical investigations across multiple indication areas. Its anti-inflammatory, antioxidant, and neuroprotective properties are particularly well studied in preclinical models, while human trials showed effects on cognition, sleep, mood, and oxidative stress markers. The safety and tolerability of rosmarinic acid-containing extracts are documented in short- to mid-term studies, with dosages of 500–1000 mg/day causing no serious adverse effects.

While some applications, such as knee osteoarthritis, have been investigated in clinical studies, other areas (e.g., antiviral or oncological effects) still require further clinical research. Preclinical data on fatigue in cancer models suggest promising mechanisms, but human studies are needed to confirm these effects. Systematic gaps remain, particularly in long-term use, optimal formulation for maximum bioavailability, and the study of synergistic effects with established therapies.

3. How Robust Is the Research?

Research on rosmarinic acid encompasses a substantial body of preclinical work alongside a smaller set of human studies. Controlled human studies focus on three main areas: cognition, safety/tolerability, and fatigue. Other applications, such as inflammation or immune function, are represented by single studies, while oncology remains largely unexplored in human trials. The most frequently cited works date from recent years and primarily investigate Melissa officinalis extracts, which contain rosmarinic acid alongside other polyphenols. A notable limitation is the lack of standardisation in extracts: while some studies use pure rosmarinic acid, others rely on combination products, making it difficult to isolate the specific effects of rosmarinic acid.

Methodologically, the field is heterogeneous: some controlled studies are randomised and double-blind, yet sample sizes are small and intervention durations short. The most cited work on pharmacokinetics and safety reported no severe adverse effects, though long-term data are still lacking. Cognitive studies rely on questionnaires and cognitive tests, while biochemical markers are rarely assessed. Preclinical data suggest antioxidant, neuroprotective, and anti-inflammatory mechanisms, though these findings remain to be confirmed in humans. Review articles summarise these mechanisms but emphasise the need for clinical trials in specific applications.

4. What Is Often Claimed — and What the Data Support

5. Profile: Molecule and Charge

Rosmarinic acid is not a single molecule but a mixture — there is no molecular formula and no fixed molecular mass. What can be described are functional groups, charge behaviour, and redox properties; this is the focus of the next section.

6. Charge, Electrons, Radicals

Rosmarinic acid exhibits electrochemically relevant properties due to its phenolic hydroxyl groups and the caffeic acid-like structure, which are crucial for radical scavenging and redox activity. The two terminal phenolic OH groups enable electron transfer and stabilise reactive oxygen species (ROS) 8 17. In human tissue, strong radical scavenging capacity was measured: DPPH-IC₅₀ values of 17.26–22.81 µg/ml and ABTS-IC₅₀ values of 27.91–33.6 µg/ml 15. The antioxidant effect correlates with a high total antioxidant capacity (up to 476.57 µg AAE/mg) and a Ferric-Reducing-Antioxidant-Power (FRAP) of up to 637.727 µM TE/mg 15. Hydroxyl radical scavenging (IC₅₀ = 64.12 µg/ml) and hydrogen peroxide scavenging (SC₅₀ = 99.2 µg/ml) have also been demonstrated 16.

Proven In humans, rosmarinic acid has been confirmed as an ROS scavenger: in cell models, it reduced reactive oxygen species and increased antioxidant capacity, both in healthy and cancer cells 9 13. The effect is associated with modulation of redox-sensitive signalling pathways, including NF-κB and Nrf2. Computational analyses show that rosmarinic acid binds to inflammatory mediators such as 5-LOX (-7.6 to -8.7 kcal/mol) and COX-2 (-8.8 to -10.2 kcal/mol), with hydrogen bonds and hydrophobic contacts stabilising the interaction 14. The negative surface charge of rosmarinic acid formulations (e.g., in nanoparticles) contributes to colloidal stability but is not directly associated with cation exchange. The next step would be to examine how the electrochemical properties affect bioavailability and interaction with endogenous redox systems in vivo.

7. Interactions with Other Substances

With which other substances on the platform this substance has been jointly studied or discussed in human studies and review articles — combinations, comparisons, or shared mechanisms of action. The number indicates studies in which both substances were present.

Rosmarinic acid showed inhibition of the enzyme CYP3A4 in human tissue with an inhibition potential of 0.936 (hERG: 0.856), indicating potential interactions with drugs metabolised by this enzyme. Mild inhibition of the enzymes CYP1A2 (IC₅₀: 497.45 ± 9.64 µg/mL for Vaccinium floribundum extract; 719.72 ± 11.37 µg/mL for Baccharis pentlandii extract) and CYP2D6 (IC₅₀: 637.15 ± 14.78 µg/mL and 588.70 ± 11.01 µg/mL, respectively) was also observed. These findings are from preclinical models and require validation in vivo, particularly to clarify the clinical relevance of the inhibitory concentrations.

Whether these interactions also occur with systemic administration in humans remains to be determined. The next step would be to examine whether the observed synergies are due to altered pharmacokinetics (e.g., enzyme inhibition) or direct cellular interactions.

8. Overdose, Tolerability, Limits

In controlled human studies, rosmarinic acid showed no toxic effects at daily doses of 500 mg to 900 mg over periods of up to 96 weeks. In a 24-week placebo-controlled double-blind study in Alzheimer’s patients (mild dementia), a daily dose of 500 mg rosmarinic acid (from Melissa officinalis extract) was deemed safe and well tolerated; adverse effects did not occur more frequently than with placebo 2 2. Even at higher doses (600 mg and 900 mg/day for 90 days), hormonal parameters (FSH, LH, TSH), vital signs, blood chemistry and haematology remained unchanged 19.

Proven In studies with cancer patients (solid tumours), mild adverse effects occurred under rosmarinic acid (dose not specified): vomiting (0.9 %), fever (5.4 %) and headache (2.7 %) 7. Contraindications or upper limits for intake cannot be derived from the available human studies. Plausible: Polyphenols such as rosmarinic acid may have sleep-promoting effects without the side effects of conventional sleep medications 20. The next step would be to examine whether dose-dependent effects or interactions with medications occur in larger cohorts.

9. The Most Robust Studies

Ordered by evidence strength, not by prominence. The full evaluation includes significantly more studies; here, the most reliable are listed.

Controlled Human Studies

• 1 Pharmacokinetics, Safety and Tolerability of Melissa officinalis Extract which Contained Rosmarinic Acid in Healthy Individuals: A Randomized Controll (2015)
• 2 Safety and efficacy of Melissa officinalis extract containing rosmarinic acid in the prevention of Alzheimer's disease progression (2020)
• 3 High-rosmarinic acid spearmint tea in the management of knee osteoarthritis symptoms (2014)
• 4 Effects of Melissa officinalis Extract Containing Rosmarinic Acid on Cognition in Older Adults Without Dementia: A Randomized Controlled Trial (2023)
• A Randomized, Double-Blind, Placebo-Controlled Trial of a Polyphenol Botanical Blend on Sleep and Daytime Functioning (2021)
• Rosemary as an adjunctive treatment in patients with major depressive disorder: A randomized, double-blind, placebo-controlled trial (2022)
• 5 Effects of <i>Melissa officinalis</i> Phytosome on Sleep Quality: Results of a Prospective, Double-Blind, Placebo-Controlled, and Cross-Over Study (2024)
• 6 Effect of Spearmint Extract Containing Rosmarinic Acid on Physical and Executive Functioning After a Tactical Operation (2018)
• Safety and tolerability of a dried aqueous spearmint extract (2017)
• 7 A phase II randomized, double-blind, placebo-controlled study of Nuvastatic (C50SEW505OESA), a standardized rosmarinic acid-rich polymolecular botanic (2024)
• Prunella Oral Liquid in combination with Western medical treatment for Graves' disease: A systematic review and meta-analysis (2026)

Observational Human Studies

• 8 Rosmarinic acid is a novel inhibitor for Hepatitis B virus replication targeting viral epsilon RNA-polymerase interaction (2018)
• 9 Enhancing the anticancer effects of rosmarinic acid in PC3 and LNCaP prostate cancer cells using titanium oxide and selenium-doped graphene oxide nano (2025)
• Proven: Unlocking the antiviral potential of rosmarinic acid against chikungunya virus via IL-17 signaling pathway (2024)
• Proven: High Rosmarinic Acid Content <i>Melissa officinalis</i> L. Phytocomplex Modulates Microglia Neuroinflammation Induced by High Glucose (2025)
• Proven: <i>Echium amoenum</i> and Rosmarinic Acid Suppress the Growth and Metastasis of Gastric Cancer AGS Cells by Promoting Apoptosis and Inhibiting EMT (2024)
• Plausible: Unraveling the Effects of <i>Melissa officinalis</i> L. on Cognition and Sleep Quality: A Narrative Review (2025)
• Proven: The chemoprotective hormetic effects of rosmarinic acid (2024)
• Hypothesis: Inducing In Situ M₂ Macrophage Polarization for Tendinopathy Therapy through Microneedle Patch-Mediated Instant/Sustained Delivery (2025)
• Proven: Protective Effect of Natural Phenolic Acids, Rosmarinic Acid and Salvianolic Acid, Against Diabetic Atherosclerosis (2026)
• Plausible: Nutritional Composition, Therapeutic Benefits, and Functional Food Potential of <i>Coleus amboinicus</i>: A Comprehensive Review (2026)
• Proven: Antinociceptive Effect and HPLC Profile of Lyophilized Chicory and Oregano Decoction (2026)
• Proven: Rosmarinic acid-eluting contact lenses as a multifunctional therapeutic system for diabetic ocular complications (2026)

Human Tissue Studies

• Proven: Exploring the antibacterial, antidiabetic, and anticancer potential of Mentha arvensis extract through in-silico and in-vitro analysis (2023)

10. Summary

Evidence: Rosmarinic acid, in the form of standardised extracts (primarily from Melissa officinalis), has been shown to be safe and well-tolerated in controlled studies, with daily doses up to 900 mg. Clinically demonstrated effects include improvements in neuropsychiatric symptoms in mild Alzheimer’s dementia, sleep quality (↑ deep sleep by 15 %), and mood enhancement in depression. It also reduces fatigue scores in cancer patients. Additionally, it exhibits antioxidant activity (↓ F2-isoprostanes) and immunomodulatory effects in autoimmune thyroid diseases (↓ FT3/FT4, ↓ TRAb). Pharmacokinetic data support daily administration, with preclinical evidence suggesting metabolites such as caffeic acid may contribute to systemic effects.

Plausibility and implications: Hypothesis: The observed effects on cognition, sleep, and mood may result from modulation of neurotransmitter systems (GABA, serotonin, acetylcholine) alongside antioxidant and anti-inflammatory mechanisms. Preclinical data suggest neuroprotective actions, including inhibition of the NF-κB signalling pathway or cytokine modulation. If these mechanisms are confirmed clinically, rosmarinic acid could become relevant in neurodegenerative diseases, chronic inflammation, or metabolic stress conditions (e.g., diabetes). Furthermore, in-vitro studies indicate potential antiviral properties (e.g., against HBV or Chikungunya virus), though human validation is lacking.

What a study should clarify: Targeted clinical research is needed to (1) elucidate the neurobiological mechanisms underlying cognitive effects (e.g., neurotransmitter modulation, inflammatory markers) in both healthy and impaired populations, (2) validate antioxidant and anti-inflammatory actions in conditions such as rheumatoid arthritis or cardiovascular disorders, and (3) assess long-term safety in vulnerable groups (e.g., pregnant individuals, chronically ill patients). Additional studies should explore structural joint changes in osteoarthritis and potential synergistic effects with established therapies (e.g., NSAIDs). For antiviral applications, early-phase clinical trials are required to determine efficacy and optimal dosing.

11. What Remains Unclear

• Dose-response relationship: Which rosmarinic acid concentration yields optimal cognitive effects? Existing studies use varying doses, but direct comparisons are lacking.
• Long-term effects: Are there cumulative benefits on cognition after prolonged use, or risks (e.g., drug interactions)?
• Mechanism in humans: Can the neuroprotective action be confirmed in clinical trials?

12. Further Paths

Topics, mechanisms and chains in which this substance appears — for those who want to look beyond the substance.

• Interaction network

Topics, pathways, and chains in which this compound appears — for those looking beyond the substance itself.