Mediterranean Diet and Zone Diet: comparing two life styles

Bivo is a complete and balanced food according to the percentages of macronutrients provided by the Mediterranean diet.

In a food style of this type, 55-60% of the daily caloric requirement derives from carbohydrates (mainly complex), 30-35% from fats(mainly mono- and polyunsaturated) and about 15% from proteins (not only animals but also of vegetable origin). Bivo is the only complete and balanced food to follow the proportions of the Mediterranean diet; many similar products have formulations with a higher protein content and often follow the “40-30-30” rule of the Zone diet. So let’s try to understand better what this rule consists of and what are the main characteristics of these two eating styles.

Let’s start with the Zone diet. In 1995 the biochemist Barry Sears published the book “The Zone diet”, where he described a food strategy that, in the panorama of diets of the time, was in many ways revolutionary. What is certain is that it was the first diet to focus attention on hormonal control which, according to Sears, can be achieved by following a particular type of diet. The control referred to in the Zone mainly concerns the balance between the production of insulin and glucagon. Insulin, in addition to being the key hormone for regulating blood sugar, is also responsible for storing fats inside the adipose tissue (ie “makes you fat”), especially if it is produced in excess. Glucagon, on the other hand, is an insulin antagonist, therefore with the opposite effect. In practice, the balance between these two important hormones is obtained only if you remain “in the zone”, that is, if you keep insulin production in a “zone” where it is neither too high nor too low. According to Sears, to achieve this it is necessary to feed following a particular distribution of macronutrients, based on the formula 40-30-30 (40% of calories from carbohydrates, 30% from proteins, 30% from fats). Once explained, albeit very briefly, the theory behind the Zone, let’s see what are its focal points:

 the 40-30-30 ratio must be respected at each meal, to simplify it is organized in “blocks”, each with the correct ratio of nutrients;

 you must not fast for more than five hours, you must eat even if you are not hungry;

 it is necessary to introduce foods and / or supplements that contain omega-3 polyunsaturated fatty acids (one of the merits of the Zone is to have enhanced the important anti-inflammatory action of omega 3 fatty acids and others of the same category);

 as sources of fat we recommend extra virgin olive oil, avocado, fish oil, dried nuts;

 egg whites, fish, bresaola, white meats, low-fat dairy products, protein powders are recommended as protein sources;

carbohydrates are to be chosen only with low glycemic index, those with high glycemic index must be avoided;

 for a better result of the Zone a constant moderate intensity physical activity is necessary

Pros and cons of the Zone diet
This diet ensures rapid weight loss; its effects would begin to occur around the twentieth day with an evident reduction of the fat, a greater one ease in increasing muscle mass with the consequent improvement of physical performance. In addition, the immune system would also benefit from diet producing greater resistance to infections. Other beneficial effects come attributed to this food style, including the improvement of diabetic pathology, of hypertension, hypercholesterolemia and atherosclerosis.
Although some of these health improvements have actually been seen in many of the people who follow the Zone, to date there is not enough literature to scientifically support this method, in particular there is no scientific evidence regarding the fact that the Zone diet is able to control insulin production in an important way and glucagon. In addition, the American Heart Association has repeatedly stressed how unbalanced protein intake causes a harmful increase in animal saturated fat.
In addition, it is an impractical diet due to the difficulty in calculating the calorie percentages for the three macronutrients. Even if the method developed tries to simplify this calculation by inserting the so-called “blocks”, the risk of abandonment or error is quite high.

However, it does have its merits, in particular having emphasized the key role of the insulin control for weight loss and the importance of the introduction daily of “good fats”, primarily omega-3.

We have analyzed pros and cons of the Zone diet, now let’s move on to the Mediterranean diet. There is a parallel between the two diets, because many of the food choices in the area are similar to those of the Mediterranean diet, which,  however, as mentioned above, it has a very different distribution of macronutrient percentages and, in the opinion of many scholars, more balanced, especially as regards the protein quota.
Remember that “Mediterranean diet” means the typical diet of the countries bordering the Mediterranean Sea, with inhabitants who in ancient times were mainly farmers or fishermen who, to survive, used the products of the fields or the proceeds from fishing and only rarely they ate meat. Therefore this lifestyle is characterized by a regular use of fresh products, often combined with each other. The consumption of seasonal fruit and vegetables, often whole grains, fish (especially blue fish), nuts and legumes is abundant.
The use of meat, on the other hand, is infrequent.
The countries of the Mediterranean basin followed this type of feeding starting from antiquity, but it was only in the 1960s that the definition began to be used  “Mediterranean diet”. The term was coined by Dr. Ancel Keys, the first scientist to demonstrate the effectiveness of Mediterranean nutrition. Since then, countless studies have shown that this food style has beneficial effects on health, helping to prevent obesity, cardiovascular disease, diabetes and even cancers.
For UNESCO, the Mediterranean diet has been “intangible cultural heritage of humanity” since 2010.
Most recently, in early 2020, U.S. News & World Report, has classified the  Mediterranean diet as the easiest to follow and the healthiest. This has been  established by referring to numerous scientific publications, in which it has been found that the Mediterranean diet is associated with a reduction in heart disease and the reduction of multiple chronic pathologies.

In conclusion, although there are some very good points in favor of health too in the Zone diet, nothing is better than “our” Mediterranean diet. And it’s not because in Italy we are “biased”, it is the world scientific community to certify it!

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Paola Salgarelli, Nutritionist Biologist, specialist in Food Science