Mediterranean Diet Magic
Much has been said about the benefits of adhering to a traditional Mediterranean diet. Several long-term studies have consistently indicated that conforming to it is associated with longevity and new studies appear regularly in leading scientific journals supporting its benefits.
The traditional Mediterranean diet isn’t a “diet” per se. Rather, it is a mix of traditional eating habits seen primarily in countries bordering the Mediterranean Sea including Spain, Italy, France, and Greece. It is characterized by large quantities of vegetables, nuts and whole grains with low intakes of meat and meat products, and low to moderate levels of fish and seafood. Dairy is mostly cheese and yogurt and dessert is often fresh fruit and cheese. Olive oil is the main source of dietary fat and, perhaps most famously, a moderate ingestion of wine with meals -one to two glasses daily for men, one glass daily for women (one glass = 5 ounces of wine).
Compared to more Western diets, the Mediterranean diet has been viewed as something of an enigma because of its relatively high fat content yet low prevalence of hypertension, cardiovascular disease, cancer, diabetes, and obesity seen in its adherents compared to populations in the United States, Australia, and northern European countries.
But what, exactly, makes it so healthy? Few attempts have been made to investigate the relative importance of the individual components but nine dietary components have been generally accepted as capturing its essence:
- legumes (plants that produce pods with a naturally occurring seam which splits open to reveal a row of seeds - peas, chick peas, lentils, beans)
- meat and meat products
- dairy products
The first seven components have been presumed to be beneficial; the last two categories, not so much.
The Greek EPIC study attempted to tease out some answers by looking at the traditional diet and lifestyle of nearly 29,000 healthy men and women, aged 20-86 years living in Greece between 1994 and 1997. The participants were followed for an average of 8.5 years. Conformity to the diet was characterized on a scale and ranged from 0 (minimal conformity) to 9 (maximal conformity). Better adherence to a traditional Mediterranean diet was associated with lower overall mortality - specifically, two additional units on the scale (“a realistic change”) correlated with a 14% lower mortality rate.
While the contribution of the nine dietary components was additive, benefits were greater for:
- moderate (rather than excessive or minimal) alcohol consumption – 24%
- low consumption of meat and meat products – 17%
- high consumption of vegetables – 16%
- high consumption of fruits and nuts – 11%
- high monounsaturated to saturated fat ratio – 11%
- high consumption of legumes – 10%
- high consumption of cereal – 5%
- low consumption of dairy – 5%
There was a non-significant increase in mortality seen with a high consumption of fish/seafood but the researchers noted that overall intake of fish/seafood in this study was quite low; its effect was “inconsequential” and likely due to chance.
Commenting about their findings, the study authors stated that alcohol in Mediterranean countries is usually consumed with meals and primarily in the form of wine (in contrast to beer used for recreational purposes as is often the case in the U.S. and elsewhere). Reports suggest that even white wines contain antioxidant compounds and that wine may modulate the health benefits of other nutritional compounds in the stomach. The higher ratio of monounsaturated to saturated fats was considered beneficial and reflects the high olive oil consumption inherent in a traditional Mediterranean diet.
While we may only dream of basking in the glow of the Mediterranean sun, we can definitely leverage the time-tested (and, incidentally, delicious) Mediterranean diet for better health.
Trichopoulou, A., Barnia, C., Trichopoulos, D. Anatomy of health effects of Mediterranean diet: Greek EPIC prospective cohort study. BMJ 2009; 338: b2337.