Learn the Key Nutrients of a Mediterranean Diet
Incorporating the balanced lifestyle of good taste and good health can be a powerful change for better heart health.
It’s a concept that is becoming common among the world of healthy eating, and proof of the Mediterranean diet’s benefits is mounting with a recent study showing about 30 percent of heart attacks, strokes and deaths can be prevented in people at high risk if they incorporate the diet’s philosophy.
Published in the New England Journal of Medicine (February 2013), the large study was the first major clinical trial to measure the diet’s effect on heart risks. After a five-year review of 7,447 people in Spain who were overweight, were smokers, or had diabetes or other risk factors for heart disease following the Mediterranean diet, the researchers were so impressed with its impact they ended the study early.
This latest study speaks volumes to a diet that is based on being rich in olive oil, nuts, beans, fish, fruits and vegetables—and little or no red meat —as optimal for heart health. And, what makes the Mediterranean diet approach so effective could be due to its easy sustainability, according to Katherine Patton, Med, RD, CSSD, LD, clinical dietitian for the Women’s Cardiovascular Center at Cleveland Clinic.
“Often patients wonder if they should follow a regimen such as a vegan diet to reduce their risk of heart disease, but we would never encourage them to jump into something that may be very difficult to live by long term. The Mediterranean diet is a lifestyle that is easy to follow and incorporate daily,” says Patton. “The diet also allows for good fats, such as olive oil, as well as red wine.”
Understanding the diet’s power
The Mediterranean diet emphasizes an abundance of foods from plant-based sources. As a diet that is rich in fruits, vegetables, legumes and whole grains, fish, nuts and low-fat dairy, the approach is based on increasing fiber as a replacement to high-fat proteins, according to clinical dietitian Julia Zumpano, RD, LD.
“High-fat protein from animal fat sources, including whole-milk cheeses, poultry with skin and fat intact, fatty cuts of red meat, which includes prime grades of meat, ribs, steaks, pork (bacon, ham, sausage), veal and lamb, are insults to cholesterol levels. Alternatively, soluble fiber can lower cholesterol levels by binding around bile (which is composed of cholesterol), removing it with the body’s waste,” explains Zumpano. “By increasing your intake of fiber and protein from plant sources, as well as the addition of healthy fats, you feel full, satisfied and have eliminated a significant source of dietary cholesterol coming from meat, poultry, cheese, eggs and added fats like butter, creamy dressings or sauces and mayonnaise.”
Soluble fiber is a key player in the Mediterranean diet, with beans and legumes and a generous amount of fruit and vegetables aiding in the removal of cholesterol. When the soluble fiber dissolves, it creates a gummy substance that traps dietary cholesterol, and bile, keeping them from entering the bloodstream. Instead of absorbing this fiber, the unabsorbed mass and the cholesterol, allow it to pass out of the body, according to Patton.
“Many patients with heart disease are also dealing with weight issues. By focusing on the good fats, such as olive oil, nuts and seeds, in addition to a high-fiber diet, they can more easily reach their goals,” says Patton.
A gut reaction
Further support of the Mediterranean diet’s method is illuminated in recent research, which shows that red meat and eggs contain compounds that raise the risk of heart attack and stroke. The research is the latest in a series of work that has shown that the population of bacteria in our guts, jointly known as the gut microbiome, can influence everything from weight loss to brain chemistry.
A study published in Nature Medicine (April 2013) shows L-carnitine, a compound found in red meat and added to energy drinks, can increase heart risk due to gut bacteria digesting it to produce trimethylamine-N-oxide (TMAO), a metabolite already suspected of clogging arteries. Shortly after, the same group of researchers led by Stanley Hazen, MD, PhD, co-section head of Preventive Cardiology & Rehabilitation at Cleveland Clinic’s Miller Family Heart and Vascular Institute, found that TMAO was also produced when eating eggs. The study published in the New England Journal of Medicine shows that the compound lecithin, found in egg yolk, also produces TMAO when digested by gut bacteria.
“The Mediterranean diet limits the number of portions and portion size of high-cholesterol foods that tend to be high in the precursors for making the gut flora metabolite TMAO,” Dr. Hazen tells Women’s Heart Advisor. “We believe this diet should be excellent for lowering the gut microbial product level that is a risk for cardiac disease, but additional ongoing research will tell us more.”