Thanks to SciTech Daily Review, I found this interesting essay from last year - Brain and Mouth Disease.

The person describing the health benefits of the Mediterranean Diet was Dimitrios Trichopoulos, Professor of epidemiology and public health at Harvard University. When we completed our respective talks we shared a cab to Washington’s National Airport en route back to our home bases. On the way I asked Dr Trichopoulos "If I faithfully follow the Mediterranean Diet, how much longer will I live?" He seemed taken aback by the remark and said something like "That’s a very interesting question. Perhaps we should put a graduate student on the problem."

I don’t know if he ever did. But a lengthy article by Gary Taubes in the March 30 issue of SCIENCE, the premier American scientific publication, suggests that the answer to my question "How much longer will I live?" is — not much. And if the analysis is correct, it will have an explosive impact on the vast industry in this country and in fact the world which is based on the notion that fat is bad and that consuming it will kill you. But as Taubes points out, 50 years of mainstream nutritional research and hundreds of millions of research dollars have not proved that if you eat a low-fat diet you will live longer. Certainly your cholesterol levels will be lower. But the link between diet and longevity it has been argued remains undemonstrated.

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Since the beginning of the 70's Americans have dropped their consumption of fat to about 34% of their calories from fat, down from over 40% beforehand. The incidence of heart disease does not seem to have declined, as a 10-year study reported in the New England Journal of Medicine in 1998. Nonetheless, the treatment of heart disease has improved enormously - with more than 5.4 million heart-related procedures compared with 1.2 million in l979. This may provide the questionable impression that it is dietary change which is responsible for improved coronary experience.

Furthermore, the replacement of fat-containing foods by carbohydrates may have contributed to an epidemic of obesity and then diabetes among Americans. The term "fat-free" on a product appears to provide permission to consume large portions of it, producing an intake well beyond what appears to be necessary to balance energy consumed and energy used. ...

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Nevertheless, humans evolved as omnivores and we seem well-equipped to eat well-balanced and moderate diets of the foods which were in our environment as we evolved - animals, fish, legumes fruits, vegetables, nuts, berries, and honey when we could get it. Ample fruits, vegetables, and nuts may deliver protective impacts and are obviously one sign of the current good gastronomic fortune of North Americans - our temperate climate provides us with a good cross-section of an ideal grocery store. And it would be irresponsible to avoid stressing exercise as a factor in healthy nutrition - we were born to run, for our dinner.

It appears that people who are committed to low-fat diets almost invariably turn to high-carbohydrate regimes, many components of which provide physiological stimuli to increased hunger. Perhaps a dab of fat will do you, to provide a satisfying experience with food and transform it from battle rations into a calmly sensible aspect of the pursuit of pleasure.

© New York Press, April 18, 2001

This well written essay balances a quest for data with common sense. I like that!