Resveratrol for Weight Loss: What the Meta-Analyses Show

Resveratrol has not been shown to produce meaningful weight loss. A 2026 meta-analysis of 23 randomized trials (1,005 adults with overweight or obesity) found a pooled weight change of −1.42 kg that was not statistically significant (95% CI −3.19 to 0.35), with a modest waist reduction of −1.93 cm as the one anthropometric measure that moved^[1]. A 2025 umbrella review read the literature more favorably, but the body-weight effect it reported was −0.18 kg^[3].

What the newest meta-analysis found

Setayesh and colleagues searched to September 2025 and restricted the analysis to adults with overweight or obesity, the people most likely to buy this supplement for weight reasons^[1]. Compared with control groups, resveratrol had no significant effect on body weight, BMI (−0.47 kg/m²; 95% CI −0.96 to 0.01), fat mass (0.47 kg; 95% CI −1.75 to 2.69), body fat percentage (−0.88%; 95% CI −1.91 to 0.15) or fat-free mass (1.42 kg; 95% CI −1.04 to 3.89)^[1]. Adiponectin and leptin, the fat-tissue hormones often invoked in marketing, did not change significantly either^[1].

Waist circumference was the exception, at −1.93 cm (95% CI −3.10 to −0.76)^[1]. Fat mass did not fall alongside it, which makes the waist finding harder to interpret as fat loss. The paper’s title says the evidence was graded, but the abstract does not give those certainty ratings, so we can’t report them here.

For scale, and only as an indirect comparison between very different trials: semaglutide 2.4 mg produced an estimated treatment difference of −12.7 kg against placebo at week 68 in STEP 1, under an estimand that counted participants regardless of treatment discontinuation or rescue interventions^[21].

Why the reviews seem to disagree

Search for resveratrol and weight and you will find headlines pointing both ways. Part of that comes from which trials each review pooled and in whom, and part from the difference between a statistically significant result and a large one. The table below draws on Setayesh 2026^[1], Sun 2026^[2], Abu-Zaid 2025^[3], Shen 2026^[4], Molani-Gol 2024^[5], Mousavi 2019^[6], Delpino 2021^[7], Lahouti 2025^[8] and Zahoor 2024^[9].

Three readings stand out. Where a body-weight effect reaches significance, it is small, from −0.18 kg^[3] to −0.51 kg^[6]. The most recent conventional meta-analyses in obesity-focused populations are the ones finding no significant or consistent weight effect^[1][4], and a smaller 2024 pool of 5 trials and 419 participants found no significant BMI effect (mean difference 0.21; 95% CI −0.970 to 1.39)^[9]. Waist is the most repeated signal, though Shen did not find it consistent^[4], and Sun’s own results list no significant waist change among patients with type 2 diabetes^[2], in contrast to Lahouti’s pooled estimate in that group^[8].

Umbrella reviews deserve a specific caution. Abu-Zaid and colleagues concluded that resveratrol could be considered a complementary therapy in obesity^[3], yet the same paper says the clinical relevance remains uncertain given the size of the effects, and notes that trial overlap between the meta-analyses it combined could overestimate or duplicate evidence^[3]. Sun and colleagues rated their waist result high certainty and reported that 54.8% of associations showed high or very high heterogeneity overall^[2].

What individual trials measured

Trials that measured body composition directly are mostly flat. In a 6-month double-blind trial, 41 overweight adults completed 150 mg/day or placebo, with no difference in body composition or liver fat, although HbA1c was lower on resveratrol (35.8 vs 37.6 mmol/mol)^[11]. In 74 men with metabolic syndrome, 16 weeks of 150 mg or 1,000 mg/day had no effect on body composition^[12]. A 4-week trial in 24 obese men found no effect on visceral fat, ectopic fat or resting energy expenditure^[13].

One weight-focused trial tested resveratrol with and without orlistat on a reduced-calorie diet. Of 161 participants selected, 84 completed 6 months. Resveratrol alone (−4.68 kg) did not differ significantly from placebo (−3.50 kg), while the orlistat-resveratrol combination did (−6.82 kg), and orlistat alone (−6.02 kg) also did not significantly differ from placebo^[10]. Heavy dropout limits how far that result can carry.

Dose: the subgroups point in different directions

Longer treatment shows up as favorable in several reviews, at about 12 weeks or more^[1][3][5][6]. Dose is where they part ways. Setayesh found weight and BMI reductions below 1,000 mg/day^[1], Abu-Zaid above 400 mg/day^[3], Molani-Gol at 500 mg/day or more^[5], and Mousavi below 500 mg/day^[6]. These are subgroup analyses, so they generate hypotheses and do not establish a dose. Absorption data do not settle it: a meta-analysis of 84 oral administrations in healthy adults found free resveratrol in blood rose linearly across doses of 25 to 5,000 mg, with substantial heterogeneity and inconsistent methods between studies^[18]. Shen and colleagues also point out that the quality and dose of commercial products vary considerably^[4]. The doses in these trials are supplement doses, a point our review of grapes and weight loss takes up from the food side.

Safety signals at higher doses

Short trials often describe resveratrol as well tolerated. In a 112-person, 12-week liver-fat trial it was called well tolerated and safe, though liver fat fell in the placebo group (−0.7%) and not with resveratrol (−0.03%)^[14]. The concerns cluster at higher doses and in older adults:

• Liver enzymes. A meta-analysis of 37 trials found no significant overall change in liver biomarkers, but alkaline phosphatase rose by 5.07 U/L at doses above 1,000 mg/day and ALT rose by 2.33 U/L in older adults, while ALT fell by 7.79 U/L in patients with liver disorders^[16]. In a small trial of men with fatty liver disease, 3,000 mg/day for 8 weeks (n = 10 per group) did not reduce steatosis, and ALT and AST rose significantly until week 6 compared with placebo^[15].
• Cholesterol. At 1,000 mg/day for 16 weeks, men with metabolic syndrome had significantly higher total cholesterol, LDL cholesterol and fructosamine than on placebo^[12]. Pooled data point the other way overall: Shen reported lower total and LDL cholesterol across 40 trials^[4], and Sun rated a small total-cholesterol reduction in overweight adults as high certainty^[2]. The rise here comes from one high-dose trial.
• Vascular markers. In a pilot of overweight adults 65 and older, sVCAM-1 and total PAI-1 rose significantly more on 1,000 mg/day (n = 9) than on 300 mg/day (n = 10) or placebo (n = 10) over 90 days^[17]. A pilot this small can only flag a question.

A 2026 umbrella review did not quantitatively analyze side effects^[2], so long-term safety remains the thinner part of this evidence base. Liver questions come up with other concentrated plant extracts too, as the data on green tea extract show.

Taking it with a GLP-1 medication

We found no human trial testing resveratrol alongside a GLP-1 medication, so any benefit or harm from the pairing is unknown. There is a drug-metabolism question worth raising. In 42 healthy volunteers, 1 g/day for 4 weeks inhibited the phenotypic indices of CYP3A4, CYP2D6 and CYP2C9 and induced CYP1A2, and the authors warned of possible adverse drug reactions or altered drug efficacy at pharmacologic doses^[19]. In a 12-person open-label study, 500 mg/day for 10 days raised carbamazepine exposure, which the authors attributed to CYP3A4 inhibition^[20].

That matters most for an oral small molecule. The Foundayo label states that orforglipron “is metabolized primarily via hepatic CYP3A4” and that CYP3A4 inhibitors “increase FOUNDAYO exposure”^[22]. We found no study of resveratrol taken with orforglipron, so this is a theoretical concern and no interaction has been shown. It is still a reason to put the supplement on your medication list.

What to raise with a prescriber

• Whether a supplement with this effect size^[1][3] is worth adding to your regimen, and whether another option has stronger support. Our graded supplement review covers the alternatives.
• Any medications processed by CYP3A4, CYP2D6, CYP2C9 or CYP1A2, particularly if you are considering a high dose^[19].
• Liver disease, abnormal liver tests or high LDL cholesterol, given the signals at higher doses^[12][15][16].