'Diets' That Promote Health (and Always Have)

The Mediterranean diet is believed to be responsible for the low rates of chronic heart disease in the 16 countries bordering the Mediterranean Sea.

Not that people haven't tried. Consider the health claims for various vitamins, minerals, and other nutrients over the years. Vitamins A and C, which are antioxidants, and carotenoids like beta carotene and lycopene were once touted as tools to fight chronic diseases like cancer. It was a logical hypothesis; people who eat a lot of fruits and veggies are healthier than those who don't. Shouldn't the chemicals that are unique to these foods be responsible? As it turns out, no. "The history has been that the first studies [to test individual nutrients] show fabulous benefits, and then as they were repeated with larger populations, better placebos, and better controls, not only were they not helping, but in some cases they may hurt," says Nestle. The poster child is beta carotene, which not only didn't stave off lung cancer but actually appeared to increase rates of the disease among smokers. (A similar outcome was reported earlier this year with vitamin E.) Now we're back to where we started: Fruits and veggies appear to be protective, but we still don't know why.

Soy was also considered as a miracle food. When Japanese people move to the West, for example, their rates of chronic diseases like diabetes and heart disease go up. Researchers naturally wondered whether missing dietary elements might be responsible. They realized that these immigrants largely gave up soy for other protein sources, so the researchers focused on isoflavonoids, a group of chemicals found mostly in soy and suspected of guarding against chronic disease, says Christopher Gardner, a nutrition scientist at the Stanford Prevention Research Center. Again, a logical assumption didn't pan out in larger studies.

But what if it's not a single chemical or food that traditionally protected the Japanese, says Gardner, but how all components of their diet interact? "Maybe it's not just the tofu but the tofu in the stir fry with the sesame oil," he says. "The frustrating thing in nutrition is that for the last couple of decades, so many studies have failed because we've isolated one nutrient at a time, when probably the benefit comes from the synergistic and additive effects of the whole diet taken together."

Having in a sense returned to the drawing board, researchers are increasingly looking at those conventional patterns of eating as models for healthful eating. Dietary patterns are most easily described by their ethnic origins. "Low-carb or low-fat diets are a man-made phenomenon," says Van Horn. "Instead, what we're talking about is the more cultural, traditional, historical eating pattern—like the Mediterranean diet."

That's the dietary tradition with the most evidence behind it; scientists have been studying Mediterranean eating patterns and their impact on health since after World War II, when diet was suspected to account for the remarkable health of people living on Crete. Since then, research has associated the Mediterranean way of eating with a host of health benefits, including protection against diabetes, cancer, and heart disease.

Of course, there's a high degree of variability among the dietary traditions that encompass the Mediterranean, says Judith Wylie-Rosett, head of behavioral and nutrition research at the Albert Einstein College of Medicine in New York. The same is true of Asian and Latin American diets. But pretty much any traditional diet is better than our current westernized diet, which is, by all accounts, a mess. "The public-health crisis we are facing is a direct result of the western diet: lots of refined, processed, and manufactured food, lots of red meat, lots of added fat and sugar, very little whole grains or fruits and vegetables," says Michael Pollan, whose latest book, In Defense of Food, lays out the case for a holistic approach to eating.