Resveratrol Side Effects, Interactions and Safety
What studies and a cancer-center summary report about resveratrol side effects, drug interactions, bleeding, hormone-sensitive conditions and who should check with a clinician first.
Content last updated . This page has not been medically reviewed.
In the human studies we read, the most common problem at high amounts was an upset stomach. The bigger open questions are medicine interactions, bleeding, hormone-sensitive conditions and kidney effects. For benefits, see resveratrol evidence for heart, blood sugar and aging claims. For the two related compounds side by side, see resveratrol vs pterostilbene.
What the sources report
Evidence kinds are labeled: human study (people took resveratrol), lab finding (cells or tissue samples, which may not happen in people), and expert summary (a cancer center reviewing the literature). Amounts below are study amounts, not advice.| Concern | What the source found | Kind of evidence |
|---|---|---|
| Stomach and bowel upset | In 40 healthy volunteers who took 0.5, 1.0, 2.5 or 5.0 g a day for 29 days, the 2.5 g and 5 g doses caused mild to moderate gastrointestinal symptoms. [2] Sloan Kettering lists nausea, gas, abdominal pain and diarrhea at high amounts. [1] | Human study |
| How the body processes medicines | In 42 healthy volunteers taking 1 g daily for 4 weeks, test results suggested slower processing through the CYP3A4, CYP2D6 and CYP2C9 pathways and faster processing through CYP1A2. [3] The authors said such amounts could potentially lead to more adverse drug reactions or altered drug effect. [3] | Human study (probe drugs, not patients' real medicines) |
| The same pathways in the lab | In human liver samples, trans-resveratrol inhibited CYP3A and UGT1A1 activity. [4] | Lab finding |
| Bleeding | Resveratrol inhibits platelet aggregation in vitro, so use with antiplatelet drugs may increase bleeding risk; clinical relevance has yet to be determined. [1] | Lab finding, expert summary |
| Hormone-sensitive cancers | Sloan Kettering advises caution because, in lab conditions, resveratrol showed estrogen-like properties and activated both estrogen and androgen receptors. [1] | Lab finding, expert summary |
| Kidneys | A study of a high-dose micronized formula in people with multiple myeloma was stopped because of serious adverse events that included renal failure. [1] | Human study in a specific illness and formulation |
| Heart-risk markers | A 2024 review of 10 trials in older adults reported no significant adverse events, but at high doses resveratrol increased some biomarkers of cardiovascular risk in overweight people. [5] | Human studies |
The two healthy-volunteer studies enrolled 40 and 42 people and lasted about 4 weeks. [2][3] They cannot tell how often a problem happens in everyday users.
Medicines and conditions to raise with a clinician or pharmacist
- Blood thinners and antiplatelet medicines. Sloan Kettering says to talk with your healthcare provider if you take blood thinners such as warfarin, because resveratrol may increase bleeding risk. [1]
- Medicines handled by CYP3A4, CYP2D6, CYP2C9 or CYP1A2. A pharmacist can check whether your medicines use these pathways. [3]
- Cancer treatment or a hormone-sensitive cancer. Tell your oncology team about every supplement. See integrative care during cancer treatment and antioxidants and medicines.
- Kidney disease or an upcoming operation. The sources we read do not give kidney-disease or pre-surgery rules for resveratrol. Because of the bleeding question, tell your surgical team; see supplements before surgery.
Do not stop or change a prescribed medicine on your own. Your prescriber or pharmacist can advise. More general guidance: medication interactions.
Pregnancy, breastfeeding and children
Proper evidence not found. We searched PubMed for resveratrol pregnancy safety; the results were animal, cell or review papers, and none was a human safety study we could verify. The Sloan Kettering page does not address pregnancy or children. Lack of evidence is not proof of safety. See pregnancy and breastfeeding.Limits to keep in mind
- A 2024 review of older adults said the best amount, long-term effects and interactions with medicines still need well-designed trials. [5]
- Sloan Kettering notes the claim that resveratrol extends life comes from yeast cells and has not been shown in humans. [1]
- In the US, dietary supplements are not approved by the FDA before they are sold. [6] For product quality, see quality testing and certifications.
Frequently asked questions
What are the most common resveratrol side effects?
In a study of healthy volunteers, 2.5 g and 5 g a day for 29 days caused mild to moderate gastrointestinal symptoms. [2] Sloan Kettering lists nausea, gas, stomach pain and diarrhea at high amounts. [1]
Does resveratrol interact with blood thinners?
It may. Resveratrol slowed platelet clumping in lab tests, and Sloan Kettering says it may increase bleeding risk with warfarin; clinical relevance is not yet determined. [1] Ask your prescriber or pharmacist.
Is resveratrol safe after a hormone-sensitive cancer?
Sloan Kettering advises caution because resveratrol showed estrogen-like effects in lab conditions. [1] Ask your oncology team before using it.
Is resveratrol safe in pregnancy or for children?
Proper evidence not found in the sources we read. Ask a clinician before using it in pregnancy, while breastfeeding or for a child.
Does resveratrol protect the heart or lengthen life?
A meta-analysis found no benefit on cardiovascular risk factors, and the life-extension finding is from yeast, not people. [1] Benefit evidence is covered on the linked evidence page.
References
- Resveratrol. Memorial Sloan Kettering Cancer Center, About Herbs (US). Read 2026-10-23.
- Repeat dose study of the cancer chemopreventive agent resveratrol in healthy volunteers: safety, pharmacokinetics, and effect on the insulin-like growth factor axis. Cancer research (2010). PubMed abstract. Read 2026-10-23.
- Resveratrol modulates drug- and carcinogen-metabolizing enzymes in a healthy volunteer study. Cancer prevention research (Philadelphia, Pa.) (2010). PubMed abstract. Read 2026-10-23.
- Comprehensive Investigation of Stereoselective Food Drug Interaction Potential of Resveratrol on Nine P450 and Six UGT Isoforms in Human Liver Microsomes. Pharmaceutics (2021). PubMed abstract. Read 2026-10-23.
- Effects and safety of resveratrol supplementation in older adults: A comprehensive systematic review. Phytotherapy research : PTR (2024). PubMed abstract. Read 2026-10-23.
- Turmeric: Usefulness and Safety. National Center for Complementary and Integrative Health (US). Read 2026-10-23.