Mediterranean diet does have overall
life-extending benefits

This article is excerpted from Harvard Health Publications of  March 18, 2008. The Mediterranean region includes many countries, and the dietary staples in each vary as much as the people and countryside. But it’s the shared eating habits of this region that seem to matter most.

It’s been almost 40 years since researchers linked the eating patterns of Greece, Italy and other Mediterranean countries to their low rates of heart disease. There have been some bumps along the way, but over all, the basic findings about the healthful effects of the Mediterranean diet have held up well.

The evidence isn’t just epidemiologic, nor are the benefits limited to the heart. Randomized trials have shown that a Mediterranean diet has benefits for people with rheumatoid arthritis and may help reduce colon cancer recurrence. In 2007, Harvard researchers published a study suggesting that Mediterranean eating patterns might cut people’s chances of developing chronic obstructive pulmonary disease (COPD) in half.

Taming individual diseases is certainly a big step in the right direction, but that doesn’t necessarily mean longer life. Smaller studies have hinted, though, that the Mediterranean diet does have overall life-extending benefits, and a large European study (involving 75,000 people from nine European countries) also came to that conclusion in 2005.

There was more encouraging news late in 2007, when the Archives of Internal Medicine published results from an American study. Using food consumption questionnaires collected as part of the National Institutes of Health–AARP Diet and Health Study, the researchers classified respondents by how closely their eating habits matched a Mediterranean diet and then tabulated deaths over the next 10 years.

This was a huge study that included over 380,000 Americans with no history of chronic disease. When the researchers analyzed the data, they found that high conformity to the Mediterranean diet was associated with a lower risk of death in three categories: death from any cause, death from heart disease, and death from cancer. The benefits of the diet were especially pronounced among smokers.

The Mediterranean diet may have all of these good effects because it quells the low-grade inflammation that underlies so many disease processes. It also has powerful antioxidant effects.

Main features of a Mediterranean diet

• Lots of unprocessed food from plants: fruits, vegetables, whole grains, nuts, and legumes (beans)
• Cheese and yogurt in small to moderate amounts
• Fish and poultry in small to moderate amounts
• Unsaturated fat, traditionally supplied by olive oil, in fairly large amounts
• Wine in small to moderate amounts with meals
• Red meat in small amounts and used more in sauces and as a seasoning than as a main course
• Fresh fruit for dessert

So what exactly is this life-extending diet? It’s not a diet like, say, the Atkins diet or other highly scripted weight loss plans, although people can lose weight by “going Mediterranean.” Some experts are scrupulous about referring to the “Mediterranean-type” diet in hopes of conveying that it’s a pattern, and not a rigid, single way of eating.

According to some researchers, the heart of the diet is that it’s mainly vegetarian, includes far less meat and dairy than American and Northern European diets, and uses fruit for dessert.

Olive oil is often depicted as being absolutely essential, but researchers, at least, are getting away from that. In the large European study that showed reductions in mortality, the researchers measured the effects of a “modified Mediterranean diet” that grouped the polyunsaturated fat from a variety of vegetable oils with the monounsaturated fat from olive oil. So, with respect to fats, the main thing about the Mediterranean diet is to keep your consumption of saturated fat low, which, as a practical matter, means keeping the helpings of meat and dairy products (the full-fat variety) few and far between.

Other components of the Mediterranean diet include wine in small amounts (a glass or so a day), some fish, and cheese and yogurt. The à la carte aspect of Mediterranean eating is part of what makes it appealing. Researchers and the food industry have chiseled away, trying to figure out whether there’s a particular food or nutrient that confers most of the benefit, but the whole is probably greater than the sum of any particular parts.