Resveratrol
Resveratrol is a plant polyphenol that grapes, peanuts and some berries make to fight off fungi and injury. Food gives only small amounts, supplements give hundreds of milligrams, and the body changes almost all of it within minutes.
<1 %of a swallowed dose reaches the blood as resveratrol itself
~1 g a day was well tolerated in short trials; several grams often upset the stomach
Daily reference · none: it is not an essential nutrient
- In food Grape skins also peanuts and berries
- In supplements Japanese knotweed a root extract
- Studied form Trans-resveratrol the stable shape
- Evidence in people Weak lab and animal results not repeated
From published reviews of resveratrol in people. No food figures: amounts vary widely and the food library does not measure them.
Where Resveratrol Comes From
Plants make it when they are under attack, so the amount in a food depends on the variety, the weather and fungal infection, and varies many times over.
- Red grapes and red winemostly in the skin; red wine has more than white because the skins stay in during fermentation
- Peanutssmall amounts
- Blueberries, cranberries and other berriessmall amounts
- Supplementsmostly extracted from the root of Japanese knotweed, a fast-spreading weed, and sold as trans-resveratrol in doses of tens to hundreds of milligrams
What Is Resveratrol?
Resveratrol is a stilbene, a small family of polyphenols that plants make as a defense. A grape vine makes more of it in the skin of its berries when a mold such as gray rot attacks, which is why it is called a phytoalexin: a plant's own antimicrobial.
Resveratrol, Red Wine, and Aging Research
In the 1990s, researchers looking for why French people had fairly low rates of heart disease despite rich diets pointed to red wine, and resveratrol was one suspect. Lab studies then found it switched on sirtuins, enzymes tied to aging, and it lengthened the lives of yeast, worms and flies in some experiments. Mice fed a high-fat diet with resveratrol lived longer than those on the diet alone.
Those results did not carry over well. Later studies questioned the sirtuin link, other labs could not always repeat the lifespan effects, and human trials have found small, inconsistent or no changes in blood sugar, blood pressure, cholesterol or inflammation. Reviews of those trials find no health use in people that the evidence clearly supports.
How Much Resveratrol Is in Red Wine
A glass of red wine holds from a fraction of a milligram to about 2 mg of resveratrol. Many trials gave 150 to 1,000 mg a day. Matching even the lower end would take more than ten bottles a day of a resveratrol-rich wine, enough alcohol to be deadly. Whatever wine does to the heart, resveratrol cannot be the main reason, and wine is not a way to take it.
How the Body Absorbs Resveratrol
About three quarters of a swallowed dose is taken up by the gut. The gut wall and liver then quickly attach sulfate or glucuronic acid to it, and less than 1% circulates as resveratrol itself. Researchers still debate whether those changed forms do anything, which is one reason lab results on cells, bathed in plain resveratrol, say little about people.
Resveratrol Safety and Interactions
- Stomach upsetnausea and diarrhea became common in trials at several grams a day
- Blood thinnerslab studies show it can slow clotting, so it may add to their effect
- Other medicinesit can change liver enzymes that clear many drugs; ask a pharmacist
Sources: published reviews of resveratrol absorption and human trials. Not medical advice.
Related Nutrients
Resveratrol Sources and References
The figures and claims on this page are checked against these sources.
Questions About Resveratrol
A polyphenol of the stilbene family that some plants make when they are injured or attacked by fungi. Grapes, peanuts, berries and Japanese knotweed contain it, and it is sold as a supplement.
No. Red wine has more than white because it is made with the grape skins, but the amount per glass is small. The doses tested in studies would take far more wine than anyone could safely drink.
Not in people, as far as anyone has shown. It lengthened life in yeast, worms and flies in some lab studies and helped mice on high-fat diets, but human trials have not found the same, and results in animals have also been mixed.
It is absorbed well but changed fast. The gut wall and liver attach other groups to it within minutes, so less than 1% of a swallowed dose reaches the blood as resveratrol itself.
The more stable of resveratrol's two shapes and the one used in most research. Light turns some of it into cis-resveratrol, so supplements usually state the trans content.
Doses of up to about 1 g a day were well tolerated in short trials. Doses of several grams a day often caused nausea, diarrhea and stomach pain. It may slow blood clotting, so ask a doctor first if you take a blood thinner.
No. It is not an essential nutrient and has no daily reference. Grapes, berries and peanuts are worth eating for many other reasons.
Track anywhere. On any device.
Your calorie counter and food diary in your pocket, free and without ads, with Tide one tap away.
- Log by photo, barcode or voice, right where you eat
- Steps and workouts from Apple Health and Health Connect
- The same log on your phone and in your browser, always in sync