Scientists who gave tablets containing purified resveratrol to obese men found it had some metabolic effects similar to those from exercise and caloric restriction, including lowering blood pressure and blood sugar levels. Research in animals over the past decade has suggested the compound can slow the development of age-related diseases and increase lifespan.
Researches gave 11 obese men either a daily 150mg resveratrol supplement or a placebo for 30 days. Four weeks later, the two groups swapped over so that those who took the supplements first time around were given placebos and vice versa.
Regular measurements showed resveratrol lowered blood sugar levels and improved insulin sensitivity, as well as cutting triglycerides – fats found in the blood that can increase heart disease risk. Resveratrol also reduced both sleeping and resting metabolic rate and cut blood pressure.
Previous research has shown that calorie restriction can extend lifespan in laboratory animals. Some studies suggest it also offers protection from diseases such as cardiovascular disease and type II diabetis, though this remains controversial. Calorie restriction works in a similar way to resveratrol, by triggering the production of a protein called SIRT1 which improves metabolic function and keeps cells healthy in the face of stress.Muscle biopsies carried out by Prof Schrauwen's team confirmed that participants taking resveratrol saw increased SIRT1 levels. They also strongly suggested the beneficial effects on metabolism were associated with improved functioning of mitochondria, the energy factories within cells.