Since the 1950s, the Seven Country Study suggested that the adoption of a mediterranean diet increases logevity, but may promote overweight and obesity. The Seven Country Study, which took place in Greece, United States, Italy, Holland, Yugoslavia, Finland and Japan, started at the end of the 1940s and attempted to examine the relation between diet and cardiovascular diseases.
It is one of the largest and most longstanding epidemiological studies in the world, which introduced the term “mediterranean diet” in the scientific community, along with its beneficial effects in health.
However, during the 50 years that followed, the total fat intake in the Greek diet increased, as a result of the increased availability of olive oil, as well as the introduction of other sources of fat apart from that. Consequently, the concentration of saturated fat in the mediterranean countries has increased – in fact, it has tripled.
Looking back at the date of all the studies which took place since then, one could say that the current fat consumption in Greece is very high and ranges between 35% and 47%.
Practically, this means that half the calories consumed daily are just from fat.
The consequences of these dietary changes became obvious in the health of the Greek population, which deteriorated within the last thirty years. The prevalence of obesity and diabetes increased and the majority of the adult population is either overweight or obese.
This is also due to the increased calorie consumption, along with the simultaneous reduction of physical activity. All these run counter to the high life expectancy of the Greek population and the low incidence of ischemic heart disease, constituting thus what is known as the “Greek paradox”.
The explanation of the “Greek paradox” might be sought in the protective nature of long term use of olive oil as the main source of fat, since from subsequent studies it has been shown that olive oil reduced the risk of ovarian cancer, peripheral arterial disease, even rheumatoid arthritis.
The term Mediterranean Diet is not exact, simply because there are 16 countries surrounding the Mediterranean and each one of them has adopted its own dietary model. The latter is the result of the influence of culture, economy, religion and other socio-cultural factors.
There are nonetheless common features among these dietary plans, which can be generally summarized in the following:
- High consumption of fruit, vegetables, legumes, bread and other cereal, beans, grains, potatoes and olive oil as the main fat source.
- Moderate to low consumption of dairy, poultry and fish and scarce consumption of red meat.
- The levels of egg consumptions range between zero and four times a week.
- Moderate to low consumption of wine – preferably red.
The dietary habits of the Mediterranean people include a high percentage of calories coming from fat. This is tough to contribute to the increasing rate of obesity in these countries, a fact which has started to raise concern in the scientific community.
One thing that is typical of the Mediterranean diet is its low content of saturated fat, while more than half the calories coming from fat, offer the mono-unsaturated fatty acids of olive oil.
Mono-unsaturated fatty acids don’t increase blood cholesterol levels, contrary to saturated fatty acids.
Because this type of diet is mainly based on the consumption of olive oil, there have been many concerns about weight gain of the people who follow it. In fact, many researchers have expressed the opinion that the closer the adoption of the Mediterranean diet, the higher the calorie consumption. In our days, when overweight and obesity are a very large problem, this issue is of major importance. Recent findings, however, show that the Mediterranean diet is in no way related with weight gain.
Overweight is a general problem of Mediterranean populations and most likely it is associated with the limited physical activity, coupled with increased calorie consumption.
But, what are the main characteristics of traditional Mediterranean diet? And why so much fuss? Let’s look in more detail:
Certainly the frequent consumption of fruit and vegetables is a must for a healthy body. By frequent consumption we mean 2 or 3 fruit daily and the consumption of vegetables with the main meals (mostly as a salad, but also cooked or boiled vegetables).
The low caloric density of these foods, as well as their content in vitamins, minerals, micronutrients and antioxidants make fruit and vegetables invaluable allies in the struggle against obesity.
Moving on, the daily consumption of cereals and grains is a key element of the traditional mediterranean way of eating. When we talk about cereals and grains, we refer to whole wheat bread and pasta, brown and black rice, couscous, groats, frumenty, etc.
Like fruit and vegetables, the high fiber content of these foods is very important for the proper function of the digestive system and the maintenance of blood glucose in normal levels.
The latter is an important objective in the effort to fight obesity and to lose weight, as the better the blood glucose is regulated, the lower the risk to store fat in the body.
The general guidelines for adults suggest to consume 8 micro-portions of cereals and grains daily. A micro-portion equals to a slice of bread (25gr.) or have a cup of cooked rice or pasta.
One of the hallmarks of the Mediterranean diet is the consumption of legumes, at least couple of times per week. Legumes are a particularly interesting food group, since they are a good source of plant proteins, without the triglycerides, cholesterol and saturated fatty acids found in red meat. The traditional consumption of legumes combined with grains (e.g. lentils or chickpeas with rice) is an excellent source of high biological value proteins, with low caloric content, rich in antioxidants and fiber.
As for red meat, the mediterranean guidelines suggest to have it no more than once or twice per month, and in a small quantity. People should prefer to focus on fish (1-2 times per week), and poultry (chicken, turkey) or other lean meats (such as rabbit) which should be consumed once per week.
Finally, the beneficial effect of moderate alcohol consumption in the heart function is translated into 1 glass of red wine for women and 2 glasses for men, per day.
Apart from the beneficial role of Mediterranean diet, keeping a healthy weight and having a good health altogether also depends on a high physical activity level. The increase in obesity that is observed the last years shows the need for a change in our diet and to start applying a mediterranean way of eating and living.