Resveratrol may mimic the metabolic effects of calorie restriction in obese men
Numerous in-vitro and animal studies have investigated the role of resveratrol as a mimetic of calorie restriction, but these results were yet to be replicated in humans. Researchers from The Netherlands have now demonstrated that 30 days of resveratrol supplementation mimicked the metabolic effects of calorie restriction in a small sample of healthy, obese individuals.
Resveratrol is a compound that is naturally found in the skin of red grapes, peanuts, dark chocolate and red wine. It is produced when their plants are being attacked by pathogens. Resveratrol can also be produced chemically. In animals it has been demonstrated that resveratrol, similar to calorie restriction, directly or indirectly activates a protein called SIRT1, which promotes metabolic function and healthy aging. So, the researchers of this study wanted to investigate the metabolic effects of resveratrol supplementation in human subjects.
Eleven healthy, obese men were randomly divided into two groups. One group received 150 mg of trans-resveratrol daily, the other group ingested a placebo for 30 days. After a 4 week wash-out period the groups and treatments were swapped for an additional 30 days. Just as a reference: 150 mg of resveratrol equals to 150 glasses of red wine, so the dose used in this study can’t be obtained from the diet and requires supplementation. Obese subjects were chosen because of their higher risk of developing type 2 diabetes. Body weight, energy expenditure, fat storage, blood pressure, mitochondrial function and plasma markers among other measures were measured before and after each treatment.
Resveratrol significantly reduced blood glucose levels, improved insulin sensitivity (HOMA index) and lowered plasma triglyceride levels. Resveratrol supplementation also reduced several markers of inflammation, blood pressure, sleeping and resting metabolic rate. There was also a shift in fat storage from liver to skeletal muscle along with an increase in mitochondrial function and SIRT1 production in the muscle, however no change in body weight was observed. Most of these metabolic changes are also seen during calorie restriction and/or endurance exercise. They also checked for side effects, but no adverse effects of supplementation were found.
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It seems that 30 days of resveratrol supplementation mimics the metabolic effects observed during calorie restriction, at least in healthy, obese men. It should be noted that these effects were modest compared to the effects of diet and exercise. Furthermore, it appears that resveratrol should not be used as a weight loss supplement, since it wasn’t able to increase 24-hour metabolic rate. Weight loss requires an increase in calories burned, therefore metabolic rate needs to go up. Moreover, they conclude that: “future studies should investigate the long-term and dose-dependent metabolic effects of resveratrol supplementation in order to further establish whether resveratrol supplementation has the potential to overcome the metabolic aberrations that are associated with obesity in humans”.
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Timmers, S., Konings, E., Bilet, L., Houtkooper, R. H., Van De Weijer, T., Goossens, G. H., et al. (2011). Calorie restriction-like effects of 30 days of resveratrol supplementation on energy metabolism and metabolic profile in obese humans. Cell Metabolism, 14(5), 612-622.