Xanthohumol Simply Explained

1. What It Is About

Xanthohumol is a plant substance from hops. Hops are mainly known from beer brewing. Xanthohumol belongs to a group of colour and protective substances called flavonoids. Such substances are formed by plants to protect themselves against stress and pathogens. In the hop plant, xanthohumol presumably performs a similar protective function. For studies, it is obtained from hop extracts or produced artificially.

An important point is how much of the substance reaches the body at all. Xanthohumol is only partly absorbed in the intestine. Part of it is metabolised in the liver, another part is altered by intestinal bacteria. This produces new substances that may act differently from the starting material. How much ultimately reaches the body varies from person to person. This explains why studies using the same amount often produce different results. Research focuses mainly on whether xanthohumol can reduce inflammation and what it does to the intestinal bacteria.

2. What Studies Show

The best-studied effects so far are those of xanthohumol on the genome and on inflammation.

In a study with 22 healthy adults, participants drank a beverage containing xanthohumol for several weeks. Afterwards, their white blood cells showed fewer genome lesions. The genome, DNA, is the blueprint of every cell, and oxidative stress can damage it. The participants’ urine also contained less of a breakdown product that forms during such damage. Other measured values, for example relating to hormone balance or sugar and fat metabolism, did not change 1.

Results were clearer in severely ill COVID-19 patients. In a study with 50 people on the intensive-care unit, one group received a hop extract high in xanthohumol while the other group received a placebo without active ingredient. After seven days, fewer people in the extract group had died than in the placebo group, and the course of the disease was shorter. Inflammatory markers in the blood were also lower 5 7.

The XMaS study series followed healthy adults for eight weeks. The overall composition of the intestinal bacteria changed little. In some participants, however, individual bacterial groups shifted, depending on which bacterial species predominated at the start. This is referred to as different enterotypes. How much of the xanthohumol breakdown products reached the blood varied greatly from person to person 3. In the safety assessments of the same series, only mild complaints occurred and at the same frequency in both groups 2 4.

Another study compared two preparations. With a special form that encapsulates the substance in tiny fat globules, significantly more xanthohumol reached the blood than with the simple form. In the short term, however, this did not change resting energy expenditure, blood pressure or pulse rate 6.

3. What Remains Unclear

Many of the human studies are small and mainly examined whether xanthohumol is well tolerated. How it acts with longer-term intake has not been tested; such studies are still pending.

Whether the observed shifts in intestinal bacteria have any health implications remains open. Researchers do not yet know whether these shifts, for example, lead to fewer inflammatory processes.

For cancer and viruses there are so far only cell and animal experiments. Such an effect has not been investigated in humans. An upper limit for the amount is also unknown, because studies with higher amounts over longer periods are lacking.

4. What This Means in Everyday Life

Xanthohumol occurs in hops and therefore in a food that many people know. The studies, however, used special preparations, not the amounts ingested through the diet. Whether and how much of the substance from foods reaches the body was not the subject of these studies.

The results so far come from small groups and short periods. They show that the substance can produce effects in the body, but not that it treats a disease.

The next step would be to clarify whether the changes in intestinal bacteria also relieve symptoms and whether the results can be confirmed in larger groups over longer periods. As long as this remains open, xanthohumol is a substance that research is only just beginning to understand in detail.

All details with study numbers and sources: detailed page on xanthohumol. For children: Xanthohumol for children.