The Metabolic Diet was elaborated and developed by Dr. Mauro G. Di Pasquale, Canadian doctor of clear Italian origins, who in 2000 published his work The Metabolic Diet: The revolutionary diet that explodes the myths about carbohydrates and fats. In the presentation of the book, Dr. Di Pasquale defines it as “the holy grail of diets”, a model capable of becoming the panacea for many nutritional ills.
Fundamentals of metabolic nutrition
Initially spread in the body building environment, where the alternation of the consumption of carbohydrates and fats according to particular dietary plans, the diet of the metabolic revolution is very widespread especially in view of competitions and programs aimed at losing excess fat while preserving muscle mass. Subsequently it has affected various other categories of people to become today, especially in the United States, one of the most followed diets.
Dr. Di Pasquale argues his dietary beliefs starting from a somewhat forced criticism, in my opinion, of the most modern and now consolidated nutritional knowledge and beliefs: that is, that excess fats in the diet, and particularly saturated fats, can constitute a danger to our health.
In fact, he goes directly to attack a well-known Finnish epidemiological study, the Framingham Study, begun in the 1950s in northern Karelia (Finland) and still a milestone in scientific achievements in terms of health and nutrition. Of this study, he criticizes the role played in atherogenesis (arteriosclerosis of the arteries) by saturated fats and the protective effect against it of monounsaturated (olive oil) and polyunsaturated (seed oil – omega3 fatty acids) fats.
How the metabolic diet works
In practice, its foundation is based on the unloading of carbohydrates with, on the contrary, a diet rich in fats and proteins for an initial period of 4 weeks, a metabolic shock is createdcapable of determining weight loss: by reintegrating carbohydrates in a subsequent phase according to specific methods, the inevitable process of muscle catabolism would be prevented, avoiding “too much” affecting the lean mass.
Metabolic diet: example
The basis of this diet is the alternation of loading and unloading phases of carbohydrates.
First phase: carbohydrate unloading
A first phase of 4 weeks is characterized by a drastic reduction of carbohydrates. The first 12 days include a reduced amount of carbohydrates introduced daily (30 grams) and many fats (50-60%) and proteins (30-50%). This period is called “carbohydrate dumping”and is followed by 2 days of “loading” characterized by the reintroduction of many carbohydrates (35/55% of carbohydrates – 25/40% of fats -15 / 30% of proteins).
According to Dr. Di Pasquale with an alternation of consumption of this kind would induce one’s organism in fact to “burn” body fats. This first phase is often characterized by the onset of asthenia, nausea, headache for which symptoms a series of solutions is envisaged consisting of a gradual increase in the glycidic intake (variable from person to person) until reaching the optimal amount of carbohydrates for that person and only for that.
Second phase
When this quota has been identified by the person himself, and in any case generally no earlier than 4 weeks,periods (days) of “unloading” will alternate followed by periods (days to a lesser extent) of “loading” with the previously identified glycidic content . In this way, according to dr. Di Pasquale, the organism, having identified the most suitable glucose regimen for each one, would become a perfect fat-burning machine without any undesirable effect thanks to the previously identified glucose content and on which we have calibrated the diet program. The diet program includes a duration aimed at achieving the desired weight, followed by an appropriate maintenance diet.
Pros and cons of the metabolic diet
The merits of this diet, if we can speak of merits, are that usually valid results are obtained in terms of weight reduction, without the problem of hunger (satiety with this diet is guaranteed), of the “food craving” so feared by Americans (compulsive craving for sugars and / or fats) especially in a short time: in two months, in fact, it would be possible to easily lose 8-10 kg without affecting and only for a very little the lean mass so coveted by body builders.
In truth , the defects of this diet abound and let’s see why:
- the carbohydrate unloading phase brings a very small amount of this nutrient (30 g), which is well below that required by the body, which will be forced to rapidly burn all the glycogen (hepatic glucose reserve) for the needs above all of the brain and erythrocytes that we know only use glucose (about 180 grams per day: six times higher than that recommended by this diet);
- once this supply is over (usually in 24 hours), the share of body fat begins to affect and subsequently proteins (B-series fuels) which will provide, much more slowly and at a higher metabolic price, energy with a large accumulation of nitrogenous waste and radicals free;
- the low intake of fruit and vegetables (rich in carbohydrates) also determines a depletion of mineral salts, vitamins but above all of fibers with the real risk of onset of constipation with all the problems that can derive from it (hemorrhoids, diverticulosis, etc);
- the scarcity of carbohydrates with the subsequent recourse to the metabolic consumption of fats and proteins, determines the rapid onset of a high proportion of ketone bodies (metabolic acidosis) in the blood which, if on the one hand, significantly reduces the sense of hunger, another determines the onset of fatigue, nausea, vomiting, dizziness, emotional instability, anxiety, headache up to, in the most severe cases, metabolic coma;
- the energy efficiency, especially in those who do prolonged sporting activity, is decidedly decreased since, for the same amount of oxygen consumed, carbohydrates have an energy efficiency higher than fats and therefore the sporting performance would be damaged both for minor activities and for competitive activity;
- the need to drastically increase the lipid content, requires the daily consumption of high amounts of mainly animal fats (therefore a lot of red meat, cheeses, whole milk, bacon, eggs, etc.) in spite of all the recommendations of the international scientific community on the consumption of these recognized foods (if their consumption is excessive), responsible for the increased risk of atherosclerosis : the result is a sure increase in cholesterol and triglycerides which certainly is not desirable for anyone, without taking into account gastroduodenitis always lurking in these cases.
Criticisms of the metabolic diet
The Metabolic Diet of Dr. Di Pasquale does not follow in my opinion and according to the opinion of many colleagues, the modern acquisition of Food Science in terms of metabolic response and health for the organism.
It does not take into account the forced repercussions on glucose metabolism with the onset of dangerous hyperinsulinemic peaks, it does not take into account the increase in the blood lipid level of both cholesterol and triglycerides; it does not take into account the forced reduction of fibers with negative repercussions on the entire gastrointestinal system; it does not cause an improvement but rather a worsening of physical performance with a reduction in physical resistance to effort. And I could go on but I will stop here, for reasons of space, with a decidedly negative judgment on the goodness of this food model which is much criticized by all nutritional scientific circles, but much followed only for the rapid effect it determines.
