From the Science-Based Medicine blog:
“Overweight and obesity are also diseases of modern civilization which is [sic] characterized by abundance and an increasingly sedentary lifestyle. Further, the food industry is driven by market forces which favor tasty foods, which often means being high in fat and/or sugar.
The public, understandably, simply wants to know what diet is optimal for reducing cardiovascular risk and maintaining a healthy weight. Ironically, we already have the answer, in my opinion, at least the “90% answer.”
I also think that most people know the answer – engage in regular exercise and eat a moderate varied diet with plenty of vegetables. If you do that you are most of the way to an optimal diet, and all the controversy is essentially over that last few percentage points of minimizing risk by optimizing diet.
The people who seem to have the highest stake in those last few percent are the self-help industry and the various food industries. The self-help industry want to sell you the optimal diet, and so they have a vested interest in coming up with some diet schtick and selling it – the Atkins diet, the Zone diet, the South Beach diet, etc.The one diet that seems to have the most science behind it is the Mediterranean diet. That is probably because it is a moderate diet, nothing extreme.”
Advanced Mediterranean Diet 