Want Resveratrol? Just Drink 500 Glasses of Wine
You've likely heard of resveratrol. It's a substance thought to extend lifespan, and it's that specific property that well-to-do urbanites sometimes use as an excuse to buy and drink their pricey wines.
The excuse doesn't really work, at least not how the rich urbanites hope it does. Sure, resveratrol activates certain proteins known as sirtuins that have some positive effects on the aging process, but the effect is likely heavily reliant on dosage.
Assuming the average red wine contains 1.0 milligram of resveratrol per 5-ounce glass (the range is actually 0.03 mg. to 1.07 mg.), you'd probably have to drink 500 glasses, every day, to have a fighting chance of reaping resveratrol's alleged life-extending effects.
Of course, all that alcohol (and sugar) would kill you pretty quickly, resveratrol or no resveratrol.
That's not to say minuscule amounts of resveratrol and other polyphenols aren't good for you. They are. It's just that people confuse general, long-term health effects with specific therapeutic effects.
I'll give you an example. Taking an 80 mg. baby aspirin is thought to confer a lot of healthful effects, including making it harder to develop colon cancer. But if you want to take aspirin to address a specific ailment, like headaches, you've got to take at least eight times that baby-aspirin dosage.
It's much the same with resveratrol. Taking small amounts, like that contained in a glass or two of wine, is healthful in the long run. But if you want to use resveratrol to achieve a specific outcome, like extending lifespan, inhibiting aromatase (the enzyme responsible for converting testosterone into estrogen) inhibition, maybe reducing total body fat, or possibly improving motor function, you need to take more than you'd find in a glass of wine or handful of grapes. You'd need to take a resveratrol supplement. Or drink 500 glasses of wine.
But whether resveratrol can really extend lifespan, for instance, is hard to prove, at least in humans. You can do it in roundworms and such because they don't live long, and they don't have lawyers that can sue you for unethical treatment.
The other beneficial effects are easier to prove, though, and a new meta-analysis of resveratrol's effects that just hit the streets of academia presents some pretty strong evidence.
Qian Zhou and his colleagues combed through the databases looking for resveratrol-relevant research. After excluding duplicates and non-relevant articles, they ended up with 25 articles that comprised 1,171 participants – 578 in the placebo group and 593 in the intervention group.
They found that varying doses of resveratrol (from 100 mg. to 1,000 mg.) administered daily in durations ranging from one month to six months exerted the following effects:
- Significant decrease in waist circumference.
- Significant decrease in hemoglobin A1c. (The A1c is a blood test that measures your average blood sugar over three months.)
- Significant decrease in total cholesterol.
Resveratrol, however, didn't seem to affect leptin and adiponectin levels, two cytokines that play a complementary role in fat metabolism and body weight regulation. That means that the beneficial effects were caused by something else.
The implications are that resveratrol supplementation exerts anti-obesity effects and improves metabolic syndrome –a cluster of conditions such as high blood pressure, high blood sugar, undesirable cholesterol and triglyceride levels, and excess body fat around the waist.
How exactly it does all that is up for scientific conjecture. True, resveratrol is a natural antioxidant, but frankly, so is just about anything that comes from a plant and is digestible by animals. A more plausible (but much harder to explain or understand) explanation, first suggested by Zhang (2019), is that the beneficial effects of resveratrol are related to changes "in the expression of several lipid metabolism-related MiRNAs (microRNAs) and genes."
Another researcher, Zhuang (2019), tossed out another equally plausible but much easier-to-understand mechanism for resveratrol's effects on metabolism. He and his colleagues thought that the polyphenol improved gut immune response and microbiota function.
People carrying the right amounts and right kinds of gut microbes tend to lose body fat for a couple of reasons. Firstly, certain beneficial gut microbes produce enzymes that help break down complex carbohydrates into simple sugars, making them easier to digest and less likely to take up residence on your waistline.
Further, certain bacteria produce higher levels of short-chain fatty acids that reduce inflammation and seem to facilitate fat loss.
We don't know if that's the case with Zhou's meta-study, but the effects certainly jibe with his findings.
Zhou and his colleagues are seeing the results of this meta-study through glasses where one lens looks at obesity and the other diabetes. That much was clear in their conclusion:
"Taken together, these results suggest that resveratrol has a dramatic impact on regulating lipid and glucose metabolism, and the major clinical value of resveratrol intake is for obese and diabetic patients."
Terrific. But do these results have any implications for the non-obese or non-diabetic – the person who just wants a little help keeping body fat levels low? Maybe.
Certainly not all, if any, of the 1,171 collective participants in the 25 studies were diabetic or even obese, so the evidence suggests that resveratrol supplementation supports fat metabolism, even in healthy humans who just want a little help in keeping a trim waistline.
While the studies they compiled used dosages ranging from 100 mg. to 1,000 mg., taking any more than 600 mg. a day isn't likely to confer any additional benefits.
- Zhou Q et al. Efficacy of Resveratrol Supplementation on Glucose and Lipid Metabolism: A Meta-Analysis and Systematic Review. Front Physiol. 2022 Mar 31;13:795980. PubMed.