Why Heart Experts Swear by the Mediterranean Diet

When it comes to heart health, eating like an American probably isn’t your best bet. That’s because our diets are high in unhealthy fats, processed foods and lots of carbs. But one diet in particular always gets highlighted by researchers and health experts: the Mediterranean diet.

The Mediterranean diet doesn’t get plaudits from morning TV shows or nutritionists focused on weight loss. It’s more of a style of eating, rich in vegetables, fruits, lean meats like seafood and poultry and heart-healthy fats. It comes from countries along the Mediterranean Sea, namely Spain, southern Italy and Greece.

The diet isn’t that restrictive. Foods considered Mediterranean include vegetables like kale, broccoli, spinach, cauliflower and Brussels sprouts; fruits like apples, bananas, pears, strawberries, dates, figs, grapes and peaches; nuts and seeds like almonds, walnuts macadamia nuts, hazelnuts, cashews and pumpkin seeds; legumes like beans, peas, lentils and chickpeas; tubers like potatoes, turnips and sweet potatoes; whole grains like oats, brown rice, rye, barley, and whole wheat breads and pastas; fish and seafood; poultry like chicken, duck and turkey; eggs and dairy; and healthy fats like extra virgin olive oil, olives, avocados and avocado oil.

While nutrition studies have limitations, many, many studies have linked Mediterranean-style diets with health benefits; specifically, reducing the risk for certain types of cancers, Parkinson’s disease and Alzheimer’s disease. But it its biggest claim to fame may be helping prevent heart disease. In fact, in one study, researchers tracked 26,000 women for 12 years who followed the Mediterranean diet and were enrolled in the Women’s Health Study and found that participants had 25 percent less risk developing heart disease.

Researchers from Brigham and Women’s Hospital and the Harvard T.H. Chan School of Public Health studied the diet to gain a better understanding of how it works. Although researchers still don’t have a complete picture, they were able to identify three biological mechanisms that affect heart health -- changes in inflammation, blood sugar and body mass index. 

Women in the study saw a 29 percent reduction in inflammation, which is a known contributor to heart disease; 28 percent improvement in glucose metabolism and had a reduction in insulin resistance; and 27 percent lower body mass index.

In another  study, researchers split 7,500 participants into three groups for five years. Two of the groups followed Mediterranean diets (one ate more olive oil, the other more nuts) and one group followed a low-fat diet, a traditional American diet aimed at reducing cardiovascular disease risk. Participants in the Mediterranean diet groups lowered their combined risk from stroke, heart attack and death from cardiovascular disease. They also improved other cardiovascular disease risk factors, such as blood pressure, cholesterol levels, c-reactive protein levels (a marker for inflammation) and blood sugar levels.

What if you already have heart disease? The diet seems to help there as well. In a Lyon Diet Heart Study, a randomized prevention trial designed to test whether the diet can reduce risk of heart attack recurrence, found that eating a Mediterranean diet had a protective effect up to four years after a first heart attack compared to a “prudent” Western diet.

If you’re interested in the Mediterranean diet, discuss it with your primary care doctor. If your doctor thinks it’s a good idea, stock up on fresh fruits, vegetables, legumes, whole grains and nuts. Swap butter with olive oil and season your foods with herbs and spices instead of salt. Drink red wine moderation. Eat fish and poultry at least twice a week, dairy in moderation and limit red meat consumption to no more than a few times per month. And avoid sugar.