How do the French eat more fat, sugar and rich foods, plus drink more wine, but still have less heart health issues? The answer to this puzzling question, commonly known as the “french paradox,” is believed to be due to a higher intake of a specific phytonutrient called resveratrol, found naturally in “superfoods” like red wine.
Like other antioxidants and phytonutrients, such as lycopene found in tomatoes or lutein found in carrots, resveratrol is a powerful compound that regenerates the body all the way at the cellular level.
Research published over the past several decades in many medical journals, including the European Journal of Food Pharmacology and American Journal of Hypertension, found that resveratrol (in this case from red wine) decreases the risk of heart disease among other common health concerns.
Other sources include deeply colored berries, real dark chocolate and cocoa. Along with helping to keep arteries clear from plaque buildup and protecting an aging heart, this phytonutrient has many other health benefits, too — including reducing inflammation, potentially helping to prevent obesity and protecting cognitive health among the elderly.
What Is Resveratrol?
Resveratrol is a polyphenic bioflavonoid antioxidant that’s produced by certain plants and found in foods and drinks that are known to halt the effects of aging. Resveratrol is classified as a phytoestrogen because of its ability to interact with estrogen receptors in a positive way.
Plants that produce resveratrol and other types of antioxidants actually do so partly as a protective mechanism and response to stressors within their environments, including radiation, the presence of insects or other predators, injury, and fungal infections. Today, resveratrol is believed to be one of the most potent polyphenols and strongest protectors against symptoms associated with aging and free radical damage.
Studies show that the most naturally abundant sources of resveratrol (not to mention many other protective phytonutrients, vitamins and minerals) are plants, including the skin of red grapes, red wine, raw cocoa, and dark berries, such as lingonberries, blueberries, mulberries and bilberries.
Red wine is probably the best known source, mostly due to its high levels thanks to the fermentation process that turns grape juice to alcohol. During production of red wine, grape seeds and skins ferment in the grape’s juices, which have positive effects on levels and availability of resveratrol.
The benefits of resveratrol were first discovered when researchers found that yeast and other microbes, insects and animals fed resveratrol experienced an increased life span as a result. Various studies continued to confirm its amazing anti-aging benefits, demonstrated in studies conducted on fruit flies, fish, mice and nematode worms, all of which lived longer compared to control groups that were not treated with this phytonutrient.
1. Has Anti-Aging and Anti-Cancer Effects
Resveratrol is a powerful antioxidant that neutralizes free radicals produced during everyday bodily functions, such as eating and exercise. Free radical damage is accelerated due to poor lifestyle habits like smoking, eating an unhealthy diet, and in response to environmental pollution and toxicity.
If left unchecked, free radicals can damage cells and are thought to be a cause of life-threatening diseases and earlier death. Consuming plant foods high in antioxidants and phytonutrients has been shown to offer antioxidative, anticarcinogenic and antitumor benefits that protect adults from many age-related diseases.
According to research published by the Department of Pharmacology at the University of Seville in Spain,
One of the most striking biological activities of resveratrol soundly investigated during the late years has been its cancer-chemopreventive potential. In fact, recently it has been demonstrated that it blocks the multistep process of carcinogenesis at various stages: tumor initiation, promotion, and progression.
It’s believed the mechanisms for its cancer-protecting activities involves downregulation of the inflammatory response through inhibition of synthesis and release of pro-inflammatory mediators, among other activities.
2. Protects Cardiovascular Health
Because of its anti-inflammatory activity, resveratrol has been shown to offer protection against atherosclerosis (thickening of the arteries that cuts off blood flow), high LDL “bad cholesterol,” formation of blood clots and myocardial infraction.
Consuming more has also been shown to help improve circulation and have beneficial effects on glucose and lipid metabolism in some with higher risk for metabolic syndrome.
Itadori tea, one significant source of resveratrol, has long been used in Asian countries, including Japan and China, as a traditional herbal remedy for preventing heart disease and strokes.
3. Helps Protect the Brain and Cognitive/Mental Health
Resveratrol is particularly unique as its antioxidants can cross the blood-brain barrier to protect the brain and the nervous system, unlike other antioxidants. Studies done by researchers at the Nutrition Research Center at Northunbria University in the U.K. showed that resveratrol noticeably increased blood flow to the brain, suggesting a considerable benefit to healthy brain function and neuroprotective effects.
Other study findings, such as results published in the Journal of Agricultural Food Chemistry, demonstrated that even a single infusion of resveratrol could elicit neuroprotective effects on cerebral (brain) neuronal loss and damage. This resulted from increased free radical scavenging and cerebral blood elevation due to resveratrol’s effects.
4. May Help Prevent Obesity
Findings from animal studies have found that resveratrol exerts beneficial effects on rodents fed a high-calorie diet, helping prevent fat storage and regulating insulin levels. Others research has shown that resveratrol may help reduce body weight and adiposity in obese animals, which some experts believe is due to activating the SIRT1 gene that’s believed to protect the body against the effects of obesity.
It’s not totally clear how this translates to humans consuming foods or drinks like wine and berries, but studies have found links between adults eating balanced diets that include moderate amounts of wine and healthier body weights.
5. Benefits Those with Diabetes or Prediabetes
Animal studies involving diabetic rats have demonstrated that resveratrol may be able to reduce hyperglycemia and may also possibility be of use in preventing and/or treating both obesity and diabetes.
Resveratrol may be helpful for those with diabetes and prediabetes by reducing complications (like nerve damage and damage to the heart) and helping manage insulin levels. It’s known that this phytoestrogen positively affects insulin secretion and blood insulin concentrations, according to animal studies.
6. Potentially Improve Renal Function
A 2023 study on resveratrol demonstrated that it mildly improved renal function in the general adult population. Further evidence in patients with impaired renal function will be required before it can be advocated as an adjuvant therapy.
How It Works
Resveratrol works by modifying inflammation in the body, in addition to having other positive effects on hormone production, blood circulation and fat storage. Studies demonstrate that it specifically seems to work in some of the following ways:
- It limits the body’s ability to produce sphingosine kinase and phospholipase D, two molecules known to trigger inflammation. Studies have demonstrated resveratrol’s ability to suppresses the expression and activity of cyclooxygenase enzymes tied to inflammatory responses that damage tissue throughout the body. Although the body naturally produces inflammation as a means of healing and protecting itself, such as to counter bacteria and viruses as part of the immune system, a state of chronic or constant inflammation is not a healthy state to be in. It ages the body and increases risk for almost every disease.
- Resveratrol has been found to lower insulin levels, which is key to staying young, at a healthy weight and fighting diseases like diabetes. In trials, Sirtris Pharmaceuticals found that those with diabetes who took resveratrol had lower glucose and insulin levels, making it a powerful aid to a healthy lifestyle. It also has positive effects on brain-derived neurotrophic factor (BDNF) that’s involved in the pathogenesis of obesity, type 2 diabetes and metabolic syndrome. Researchers have observed that BDNF levels are lower in people with type 2 diabetes mellitus and other insulin-related problems.
- It facilitates mitochondrial respiration and gluconeogenesis. In other words, it helps the “powerhouse” part of cells (the mitochondria) that supplies cells with energy to work optimally.
- Resveratrol keeps circulation flowing smoothly, preventing arterial damage and offering protection in the brain from memory loss and conditions, including Alzheimer’s disease. It may also prevent other disorders, such as stroke, ischemia and Huntington’s disease, in addition to mental health problems like depression, schizophrenia, bipolar disorder and autism.
- It’s been shown to have positive effects on vascular endothelial growth factor — in other words repairing damaged blood vessels.
- Because it controls release of pro-inflammatory molecules, resveratrol thus has benefits for preventing autoimmune diseases. It also seems to positively alter gut microbiota and influences stem cell proliferation and differentiation.
- Finally, as a potent antioxidant, resveratrol is constantly fighting damage from free radicals that can increase cancer risk. It deeply penetrates the nucleus and mitochondria of each cell, helping repair harmful effects due to free radical damage that can alter DNA. It also modulates apoptosis (destruction of harmful cells) and therefore seems to have anti-cancer properties. Studies have found evidence of resveratrol triggering apoptosis of activated T cells and suppressing growth of tumors, in addition to acting against cancer.
As you can tell from all the benefits described above, resveratrol and sources that provide it, including red wine, are more than just powerful heart-protectors. They’re also potential brain-boosters, among many other things. People use resveratrol for all sorts of anti-aging benefits, considering research suggests that it can help:
- Provide powerful antioxidant support
- Boost the body’s ability to fight oxidative stress (or free radical damage)
- Support cellular and tissue health
- Protect against cancer
- Promote better circulation
- Protect against diabetes
- Protect memory and cognitive health
- Preventing premature signs or symptoms associated with aging, including inflammation that leads to arterial damage and joint deterioration
- Supporting a healthy digestive system and improving elimination of waste or toxic compounds
- Improve energy and endurance
Because the FDA does not regulate supplements, many health authorities are not convinced that taking resveratrol supplements or extract will have much payoff. As with all herbs and extracts, you can’t be sure exactly what you’re getting and how effective the product may be.
Dosage recommendations vary depending on your current health and symptoms, but most resveratrol supplements are typically taken in about 250 to 500 milligrams/day dosages. It’s important to point out that this is generally lower than the amounts that have been shown to be beneficial in studies, but it’s not clear if taking very high doses is safe.
Some adults choose to consume up to two grams daily (2,000 milligrams). According to the New York Academy of Sciences, studies have found resveratrol to be safe and reasonably well-tolerated at doses of up to five grams per day, but this shouldn’t be taken without speaking with your healthcare provider
It’s possible, however, to experience mild to moderate side effects at higher doses, so experts recommend starting with less until further studies demonstrate any added benefit of taking more. Resveratrol supplements may potentially interact with blood thinners like warfarin (Coumadin) and NSAID pain relievers (like aspirin or Advil), so be sure not to mix these.
Now you know the benefits of resveratrol in your diet, you may be wondering what the best source of this compound is. Below are the best foods and beverages to add to your diet (albeit in moderation) in order to consume more resveratrol:
- Red grapes and red wine. In case you’re wondering, white wine has some too but much lower amounts since the grapes’ skins are removed earlier in the wine-making process.
- Certain types of traditional teas, including Itadori tea, common in Asian countries
- Raw cocoa (dark chocolate)
Different plants supply various forms of resveratrol. For example grapes, peanuts and Itadori tea contain mainly trans-resveratrol glucosides. Red wine is primarily a source of the aglycones cis- and trans-resveratrol.
Studies show that both Itadori tea and red wine supply relatively high concentrations of resveratrol compared to most other foods. Itadori tea is a good option for people who avoid drinking alcohol or for children.
Risks and Side Effects
Although we have mentioned that red wine and cocoa are two of the best sources of resveratrol, unfortunately a diet of dark chocolate and red wine may be decadent but ultimately very unhealthy if you overdo it. The best way to obtain the benefits of resveratrol is through balance and moderation.
We recommend consuming wine in small amounts, about one glass per day or less; according to most research, up to two glasses daily for men and one per day for women hasn’t been shown to cause any health concerns. If you do choose to take resveratrol supplements, still aim to consume antioxidants naturally from a healthy diet, including a variety of fresh plant foods.
While a large body of evidence has already suggested that resveratrol has many benefits, many experts feel that before we can promote drinking more wine or taking supplements to all adults, additional research is still needed. Overall, there’s support for its positive attributes, but data is still needed to confirm its effectiveness for prevention of actual diseases in humans.
It’s still not completely known how different people react to resveratrol and if some benefit more than others. For example, people with existing cases of diabetes or metabolic defects may need to take higher doses than mostly healthy adults to get the same effects. Talk to your doctor if you plan on taking supplements and are already on other medications.
Overall, most of the benefits of resveratrol have been shown in animal studies and at high dosages. Harvard School of Public Health points out, “The dose of resveratrol administered in experiments is always much higher than you’d normally consume in a daily diet. You would need to drink a hundred to a thousand glasses of red wine to equal the doses that improve health in mice.”
That being said, resveratrol is not a cure-all and means to living a longer, disease-free life. It may be one piece of the puzzle, but the bottom line is that it probably shouldn’t motivate you to drink more wine than you already are.
- Resveratrol is a type of polyphenol antioxidant that research suggests has many anti-aging effects.
- Consuming resveratrol from red wine, berries, dark chocolate and other foods is believed to offer protection against cellular and tissue damage. This may help lower your risk for things like heart disease, diabetes, obesity and cancer.
- Data is still not conclusive about the benefits of taking resveratrol supplements, so for now it’s best to consume it naturally from plant foods or wine in moderation.