A new study finding that mega-doses of resveratrol, a chemical in red wine, protects mice from the harmful effects of a high-fat, high-calorie diet provides support for one explanation of the "French Paradox" (the French combination of low heart disease rates with high-fat diets). It also reinforces the argument that bad outcomes commonly attributed to excess weight may in fact be due to other factors associated with (but not caused by) obesity—in this case, poor diet. The New York Times reports (emphasis added):
The researchers fed one group of mice a diet in which 60 percent of calories came from fat. The diet started when the mice, all males, were a year old, which is middle-aged in mouse terms. As expected, the mice soon developed signs of impending diabetes, with grossly enlarged livers, and started to die much sooner than mice fed a standard diet.
Another group of mice was fed the identical high-fat diet but with a large daily dose of resveratrol (far larger than a human could get from drinking wine). The resveratrol did not stop them from putting on weight and growing as tubby as the other fat-eating mice. But it averted the high levels of glucose and insulin in the bloodstream, which are warning signs of diabetes, and it kept the mice's livers at normal size.
Even more striking, the substance sharply extended the mice's lifetimes. Those fed resveratrol along with the high- fat diet died many months later than the mice on high fat alone, and at the same rate as mice on a standard healthy diet. They had all the pleasures of gluttony but paid none of the price.
Overall, I think this approach is better than starving for longevity.