What Is Resveratrol?

<p>Ken Redding / Getty Images</p>

Ken Redding / Getty Images

Resveratrol is a natural polyphenol compound in certain plants and fruits, including grapes, berries, apples, and peanuts. In supplement form, most resveratrol extracts are derived from the root of Polygonum cuspidatum, also known as the Japanese knotweed plant.

Resveratrol is rich in antioxidant, anti-inflammatory, and anticancer properties that may help relieve joint pain and benefit cardiovascular, brain, and metabolic health.

This article discusses resveratrol's potential uses, benefits, and side effects.

<p>Ken Redding / Getty Images</p>

Ken Redding / Getty Images

Unlike drugs, dietary supplements are not regulated in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed. Whenever possible, choose a supplement tested by a trusted third party, such as USP, ConsumerLab, or NSF. 

Even when supplements are third-party tested, they are not necessarily safe for all or effective in general. Talk to your healthcare provider about any supplements you plan to take and check in about potential interactions with other supplements or medications.

Active ingredient(s): Resveratrol

Alternate name(s): 3,5,4'-Trihydroxy-trans-stilbene

Legal status: Resveratrol is available as a dietary supplement in the United States and is not regulated by the FDA as a drug. However, the FDA does require that all dietary supplements have nutritional facts on their labels. 

Suggested dose: The appropriate dose of resveratrol can vary depending on the condition it is used for. As a dietary supplement, typical daily doses range from 50–500 milligrams (mg). However, higher doses have been given to subjects in some studies. Follow the product label's dosing instructions or take the dosage your healthcare provider recommends.

Safety considerations: Resveratrol is generally considered safe and well-tolerated when taken daily. Some people may experience side effects such as stomach upset, nausea, vomiting, and diarrhea. Resveratrol may cause liver dysfunction in people with non-alcoholic fatty liver disease. It may interact with certain medications and increase the risk of bruising and bleeding when taken with blood thinners, antiplatelet, and nonsteroidal anti-inflammatory drugs (NSAIDs).

Uses of Resveratrol

Resveratrol has many potential health benefits due to its antioxidant and anti-inflammatory properties.

Promotes Cardiovascular Health

Resveratrol has been studied extensively for its potential benefits for heart health, including its ability to lower blood pressure and improve cholesterol levels.

Several studies show that resveratrol's antioxidant effects can help reduce systolic and diastolic blood pressure in people with hypertension (high blood pressure) and may protect against stroke.

Other research suggests that resveratrol may improve the function of the endothelium—the inner lining of blood vessels—helping reduce vascular oxidative stress and stiffness in arteries, which helps promote healthy blood flow and protects against heart disease.

Resveratrol has also been shown to improve blood lipid (cholesterol) levels, reducing total cholesterol and triglycerides (a type of fat). High blood lipid (fat) levels are associated with increased heart disease and stroke risk. Resveratrol has been shown to decrease low-density lipoprotein (LDL), often called "bad" cholesterol, which may help protect against heart disease.

Boosts Cognitive Function

Resveratrol may boost cognitive function and protect against certain neurodegenerative disorders, such as Alzheimer's disease. Resveratrol has potent antioxidant activity that helps protect neurons (brain cells) against the effects of harmful free radicals—chemicals associated with the development of Alzheimer's disease, Parkinson's disease, and Huntingdon's.

Resveratrol has also been shown to improve the function of the hippocampus—the part of the brain responsible for memory, learning, and spatial navigation. Research shows that resveratrol's anti-inflammatory properties may protect cognitive function in older adults, helping maintain memory and cognitive function as you age.

One study found that resveratrol reduced the accumulation of amyloid-beta plaques in the brain—a hallmark of Alzheimer's disease. The study found that a 500 mg daily dose of resveratrol for 52 weeks significantly reduced amyloid-beta levels in the cerebrospinal fluid of individuals with mild to moderate Alzheimer's disease, which suggests that resveratrol may help slow disease progression.

Supports Healthy Metabolic Function

Research investigating the effects of resveratrol on metabolic function suggests that it may benefit metabolic health by helping regulate blood sugar levels and reducing insulin sensitivity, which may lower the risk of type 2 diabetes and other metabolic conditions.

Resveratrol may help manage type 2 diabetes, according to some research. One study found that resveratrol supplementation improved insulin sensitivity and reduced blood sugar (glucose) levels in individuals with type 2 diabetes. Another study found that resveratrol lowers oxidative stress in people with diabetes, which may help protect against diabetes-related complications like heart disease.

Additional studies found that resveratrol supplementation of 500 mg daily for 12 weeks reduced body weight, waist circumference, and markers of inflammation in individuals with metabolic syndrome (a group of conditions that can increase your risk of stroke, heart disease, and type 2 diabetes). Study participants had significantly improved insulin sensitivity, reduced blood pressure, and improved metabolism of lipids (a type of fat).

May Relieve Joint Pain

Resveratrol has powerful antioxidant and anti-inflammatory properties, which may help promote joint health and reduce joint pain and damage in people with certain types of arthritis.

Research suggests that resveratrol may be an effective complementary therapy and help reduce joint pain in people with osteoarthritis. In one study, a 500 mg daily dose of resveratrol supplementation significantly reduced joint pain in people with mild to moderate knee osteoarthritis when paired with standard treatment.

In another study, resveratrol effectively relieved joint inflammation and damage in people with rheumatoid arthritis (RA). It was thought to protect against certain complications of RA, such as periodontitis (gum disease) and interstitial pneumonia.

May Protect Against Cancer

Resveratrol has been investigated for its potential use in preventing cancer and as an adjuvant (additional) therapy for cancer treatments. Test tube and animal studies show that resveratrol may have anticancer properties that may help prevent or fight certain types of cancer, including breast, colon, gastric, pancreas, prostate, ovarian, and endometrial cancers.

Research shows that resveratrol may:

  • Induce apoptosis (death) of cancer cells

  • Block the growth and spread of cancer cells

  • Boost the effectiveness of standard cancer treatments, such as chemotherapy and radiation therapy

  • Inhibit certain sex hormones to prevent the growth of hormone-dependent cancers

  • Reduce chemotherapy side effects

Other Uses

In addition to the health benefits listed above, resveratrol may have other benefits. More research is needed to determine if resveratrol offers the following benefits:

  • Healthy aging: Research using animal models suggests that the antioxidant effects of resveratrol may help activate specific cellular pathways involved in promoting longevity and reducing age-related diseases.

  • Allergies: Nasal spray containing resveratrol may help reduce allergy symptoms in people with seasonal allergies, particularly hay fever.

  • Skin health: Resveratrol may improve skin health by reducing inflammation, promoting collagen production, and protecting against damage from ultraviolet (UV) radiation.

  • Eye health: Resveratrol’s ability to fight oxidative stress may protect against age-related macular degeneration, a common eye disease that can cause vision loss.

  • Immune system support: Low doses of resveratrol may support immune system function by boosting antioxidant activity and reducing inflammation.

What Are the Side Effects of Resveratrol?

Resveratrol is considered safe and well-tolerated when taken in recommended doses, but like any supplement, it may cause side effects in some people. Side effects are more common at high doses and may include:

  • Nausea

  • Diarrhea

  • Vomiting

Precautions

While resveratrol is generally safe, especially when consumed in foods, not everyone should take resveratrol supplements. People with the following conditions should avoid resveratrol supplements:

  • Nonalcoholic fatty litter disease: Resveratrol has been linked to liver dysfunction.

  • Bleeding disorders: Resveratrol increases the risk of bruising and bleeding.

  • Hormone-sensitive conditions: Resveratrol may act like estrogen in the body and should not be taken by people with certain conditions (e.g., uterine fibroids, breast cancer) that can worsen with estrogen exposure.

  • Pregnancy: There is limited research on the safety of resveratrol supplements for use during pregnancy and lactation.

Dosage: How Much Resveratrol Should I Take?

Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your needs.

The appropriate dosage of resveratrol varies, depending on the specific supplement product and intended use. Studies show that doses up to 5 grams (5,000 mg) daily are safe, but side effects are more common with doses above 2.5 grams daily.

Some research suggests that taking smaller doses is better than taking one large dose, as resveratrol is metabolized quickly.

Speak with a healthcare provider before you take resveratrol supplements. They can help you determine the best supplement and dosage based on your needs.

What Happens If I Take Too Much Resveratrol?

There is no established upper limit or recommended intake for resveratrol, and there have been no reports of toxicity or overdose in humans from dietary or supplemental sources. However, studies in rodents have shown that extremely high doses of resveratrol can lead to kidney and liver damage.

If you take very high doses of resveratrol, you may experience side effects or adverse events such as:

  • Gastrointestinal discomfort (e.g., nausea, vomiting, diarrhea, and abdominal pain)

  • Increased risk of bleeding

  • Liver or kidney damage

Seek medical attention if you suspect you have taken too much resveratrol.

Interactions

Resveratrol can interact with certain medications, herbs, and supplements, potentially causing adverse effects and changing how these medicines work in your body. Resveratrol may interact with the following:

Supplements and herbs that have similar effects or potential interactions with resveratrol include:

To make an informed decision about resveratrol supplementation, carefully read the product’s ingredient list and nutrition facts panel, which provide information on the types and amounts of ingredients included. It’s always best to review the supplement label with your healthcare provider so they can help you identify any potential interactions with foods, medications, or other supplements.

How to Store Resveratrol

Many supplements come with recommended storage suggestions on the product label, though not all do. Resveratrol supplements should be stored:

  • In a cool, dry place away from direct sunlight, heat, and humidity

  • In their original packaging and airtight containers

  • In a dark bottle to avoid light exposure, which may degrade the ingredients

If your supplement has expired or shows signs of deterioration, such as changes in color or capsules clumping together, it should be discarded. If you are unsure how to store a particular resveratrol supplement, ask for guidance from your healthcare provider or contact the manufacturer directly.

Similar Supplements

Similar supplements to resveratrol include:

  • Pterostilbene: A naturally occurring compound found in blueberries and grapes chemically similar to resveratrol

  • Quercetin: A flavonoid found in many fruits, vegetables, and grains

  • Curcumin: The active ingredient in turmeric

  • EGCG (epigallocatechin gallate): A catechin found in green tea

  • Berberine: A compound found in several plants, including goldenseal and Oregon grape (Mahonia aquifolium)

Like resveratrol, each of these supplements has antioxidant and anti-inflammatory properties that may benefit cardiovascular health, joint health, and cognitive function. Many of these compounds are being studied for their potential anti-cancer effects. Taking these supplements alongside resveratrol is generally safe, but it is important to be mindful of possible interactions or side effects.

Sources of Resveratrol & What to Look For

Resveratrol is found in several dietary sources, including red wine, grapes, berries, and peanuts. The amounts of resveratrol in these sources vary, and research shows that it is not possible to absorb the recommended therapeutic doses of resveratrol through diet alone. Therefore, supplements may be a more reliable way to ensure you get the therapeutic benefits of resveratrol.

Food Sources of Resveratrol

Resveratrol is a natural compound found in various plant-based foods, particularly in the skins of red grapes and berries. Common food sources of resveratrol include:

  • Red wine: This is, perhaps, the most well-known dietary source of resveratrol.

  • Grapes: Resveratrol is found in high concentrations in the skin of grapes, particularly in red and purple grapes. Eating grapes or drinking grape juice are excellent ways to include resveratrol in your diet.

  • Berries: Small amounts of resveratrol is in some berries, including blueberries and cranberries.

  • Peanuts: Peanuts are another source of resveratrol. The amount of resveratrol in peanuts can be pretty low, so they are not considered a primary dietary source of the compound.

Related:Red Wine and Cancer

Resveratrol Supplements

Resveratrol is available in capsule, tablet, powder, liquid, and gummy forms. Capsules and tablets are the most commonly used and can be taken with water. Liquids may be a good option if you have difficulty swallowing pills or prefer to add resveratrol to your food or drinks.

There is no evidence to suggest that one form of resveratrol is superior to others in terms of efficacy. The supplement's potency can vary, depending on the amount of resveratrol in the supplement and manufacturer. When shopping for resveratrol supplements, look for a high-quality product from a reputable brand.

Summary

Resveratrol is a naturally occurring polyphenol compound in grape skins, berries, and peanuts. It is also available as a dietary supplement. Packed with antioxidant, anti-inflammatory, and anticancer compounds, resveratrol may benefit cardiovascular, joint, and metabolic health and improve cognitive function.

If you are considering using resveratrol to support your health, talk to a healthcare provider to determine if it is safe for you, especially if you have any health conditions or are taking medications. When shopping for resveratrol supplements, choose a reputable brand, and follow the recommended dosage guidelines.