What is the Mediterranean Diet?
The Mediterranean Diet has been praised for its heart-healthy benefits, stemming out of research that was started in 1951 to investigate the low rate of heart disease in Southern Italy. At the time of the first stirrings of publicity related to the cardioprotective effects of eating a diet rich in fatty acids, whole grains, nuts, seeds, vegetables, and fish, it was not well received. Skeptics at the 1955 international meeting of the WHO (World Health Organization) challenged information gathered by the chief researcher of the Mediterranean Diet of his time, Ancel Keys (1).
Keys was asked to provide irrefutable evidence that the observations he had made in Italy after treating people for post-WWII starvation were conclusive enough to base advocating a diet so different than the standard American diet of the 1950s. Keys went on to conduct a research project entitled the Seven Countries Study, which followed cardiovascular health markers such as diet, weight, physical activity, blood pressure, blood cholesterol levels, lung capacity, and electrocardiographic measurements in men from ages 40 to 59. The subjects were from Italy, Greece, former Yugoslavia, the United States, Finland, Japan, and the Netherlands, followed for a total period of ten years (1).
Keys noted acute differences between the diets of the Italians versus the Greeks and traced it to the differences in saturated fat intakes. The Greeks consumed around 40% of their diet from fat, but Italians consumed around 30% of their caloric intake from fat. The standard American diet was rich in red meat and fat intake, and the incidences of heart attacks was much higher in middle-aged American men. Keys gradually began to tie the differences between heart health in the different countries to their intakes of saturated fats (1).
The results from the Seven Countries Study pointed out that heart attacks were 100 times higher in Finland than in Crete (Greece), and the people of Finland had high total cholesterol levels. In comparison, only 3% of the Japanese had similarly high cholesterol levels. Keys noted that the calories derived from fat sources were between 9-40% of total daily caloric intake; but surprisingly, the fat calories in the diet did not equal risk of heart attack. Greece’s fat intake was one of the highest in the study but also had some of the lowest incidences of coronary attacks (1).
What was different between countries in the Mediterranean and regions elsewhere in the world was based on the amounts of saturated fats and types consumed. Keys then labeled the eating pattern of the Mediterranean as the “Mediterranean Diet” and went on to write two books about his research. Keys was so convinced by his research that he ate a Mediterranean Diet himself and lived to the age of 100 (1).
The Mediterranean Diet is now a commonplace term among the popular dietary eating patterns that are mainstream today. The protective health benefits are now accepted and touted as one of the best diets you can follow. The Mediterranean Diet hinges on the difference between good fats derived from vegetable sources (such as olive oil) versus fats derived from animal sources (like butter, cream, milk, cheese, and meat). It does not restrict calories or restrict whole food groups, but focuses on less red meat, less fats from animals; more whole grains, fruits, and vegetables; and recommends that you slow down and enjoy your food (1).
Olive oil is featured as the best oil that you can consume on the Mediterranean Diet, but it can be hard to understand why some fats are simply better than others. It seems very counter-intuitive in our low-fat diet culture, but it’s due to the structure of olive oil. Olive oil contains monounsaturated fatty acids and polyunsaturated fatty acids. In addition, olive oil also has antioxidant properties due to the polyphenols of the olives from which it is pressed; and the olives’ phytochemicals which offer antioxidant activity. The antioxidant properties in olive oil also reduces oxidation within itself through preventing degradation of the unsaturated fatty acids (1).
You may be surprised to know that just increasing your olive oil consumption by 10 grams per day can offer you a 10% decrease in the risk of non-fatal heart-related events and a 7% decreased risk in fatal heart-related deaths (1). The striking reason for these heart benefits seem to be synergistic; while olive oil is a potent part of the Mediterranean Diet’s benefits, it is the combination of the heart-healthy fats with the whole grains, nuts, seeds, vegetables, fruits, and fish which work together to produce its benefits (2).
The Mediterranean Diet works together as a whole because the antioxidant benefits found in olive oil are also found in the phytochemicals of the whole grains and also in the vegetables and fruits. The vegetables and fruits also offer a healthy dose of vitamins. These food groups balance one another and the particular balance of fatty acids between the olive oil and the other, polyunsaturated fatty acids found in nuts and seeds balance the profile of fats in the diet (1).
In addition, the high fiber consumption from vegetables, whole grains, fruits, and legumes contribute to cardiovascular protection by inhibiting cholesterol from being absorbed in the gut and synthesized in the liver. The nuts, seeds, whole grains, vegetables, and fruit also work at the intestinal level to prevent cholesterol from being absorbed (1).
How Can We Incorporate the Benefits of the Mediterranean Diet?
It can seem like a challenge to switch over to completely adopting a Mediterranean Diet, but here are 9 simple ways that you can incorporate it into your diet:
- Choose oils over butters/margarines
Take advantage of the benefits that healthy oils can offer by choosing vegetable oils such as olive oil or canola oil. Switch to these oils when cooking, dipping bread, and try spreading olive oil over whole-grain bread products.
- Eat 3-5 servings of vegetables daily
- Choose whole-grain carbohydrate sources, such as whole-grain breads, cereals, pastas, and rice
- Choose lean protein rather than red meats
One of the major pillars of the Mediterranean Diet is reducing red meat. Red meat can still be enjoyed, but portion sizes must be taken into account (no larger than the size of a deck of cards), and lean cuts are preferred.
Choose skinless chicken, turkey, and fish. Also choose plant-based protein sources like beans and nuts.
- Eat smaller servings of dairy-based yogurts and cheeses
- Choose healthy nuts and seeds for snacking
Instead of processed food snacks, choose cashews, pistachios, almonds, and walnuts. Switch your peanut butter from standard peanut butter which contains added hydrogenated fat to natural peanut butters (the kind you have to stir). Consider trying seed pastes to spread over bread, such as sesame seed paste (called tahini).
- Season your meals with less salt and more herbs and spices
- Choose fruit for dessert
- Limit your alcohol consumption to accompany meals (one glass for women, two glasses for men) (2)
These 9 changes can make a big difference to your health and get you started on the Mediterranean Diet.
References
1. Lăcătușu, Cristina-Mihaela et al. “The Mediterranean Diet: From an Environment-Driven Food Culture to an Emerging Medical Prescription.” International journal of environmental research and public health vol. 16,6 942. 15 Mar. 2019, doi:10.3390/ijerph16060942
2. Boucher, Jackie L. “Mediterranean Eating Pattern.” Diabetes spectrum : a publication of the American Diabetes Association vol. 30,2 (2017): 72-76. doi:10.2337/ds16-0074
