Mediterranean diet healthy, studies say

DEAR DOCTOR K: In some of your columns you’ve said that the “Mediterranean diet” is healthy. First, what is a Mediterranean diet? Second, what proof is there that it really is healthy? Call me “Skeptical.”

DEAR READER: Well, “Skeptical,” prepare yourself for a fairly emphatic reply. Because when I think skepticism about something important is misguided, I tend to unload.

The Mediterranean diet is the traditional diet of people in countries near the Mediterranean Sea. The diet is rich in plant foods. These include fruits, vegetables, grains, beans, nuts and seeds. Animal protein is consumed chiefly in the forms of fish and poultry. Olive oil is the principal fat. And wine is taken with meals.

How do we know the Mediterranean diet is healthy? From hundreds of scientific studies involving hundreds of thousands of people whose health was followed for decades. Most of these studies were “observational.” They evaluated people’s diets and measured their health. In fact, there are so many of these studies, it’s hard to summarize them briefly.

But here’s my summary: People who eat a Mediterranean diet have a lower risk of diabetes, Parkinson’s disease, Alzheimer’s disease, breast cancer, colorectal cancer and prostate cancer. They also have a lower risk of dying from heart disease, dying from cancer – or dying from any cause.

And the Mediterranean diet doesn’t have any adverse side effects. But it does cost more than junk food.

If you’re a regular reader of this column, you’ll know that observational studies like those I just summarized are not as strong evidence as randomized trials. That’s true, but there also are a number of large randomized trials that point in the same direction as the observational studies.

Now, if doctors had invented a pill that reduced your risk of so many major diseases, you’d want that pill. But there already is a way for you to protect yourself against these diseases: eat well.

Maybe I’ve come on strong today. But there’s a lot of misguided skepticism about what science has shown is healthy. I want skeptics like you to know your skepticism puts you at risk.