The Dukan Diet (4 page)

Carbohydrates contain only 4 calories per gram but are usually eaten in such large quantity that the calories soon mount up. Carbohydrate calories are also totally assimilated, which increases their energy yield. Furthermore, we digest starch and flour products slowly, producing fermentation and gas, which causes bloating as unpleasant as it is unattractive.

Carbohydrates so energy-rich and easily available, and they have such a pleasant taste that they are often used as comfort foods. And, as for sweet foods, some people snack on them compulsively. Our affinity for sweet tastes is in part innate, but most psychologists agree that lengthy conditioning starting in childhood makes sweet flavors gratifying as they are associated with rewards.

Finally, carbohydrates are almost always the cheapest foods available, which is why they are served at everyone’s table, from the richest to the poorest.

As far as the body’s metabolism is concerned, carbohydrates help the secretion of insulin, which in turn encourages fat to be produced and stored.

For all these reasons, for a long time, people predisposed to being overweight were instructed to be wary of carbohydrates. Nowadays, they are told instead to be wary of the fat content in foods, which—and rightly so—has now become the overweight person’s most deadly enemy. However, this is not a reason to lower one’s guard in respect to carbohydrates, especially during the Attack phase.

The Dukan Diet excludes carbohydrates completely during the Attack phase. In the Cruise phase and until the desired weight has been reached, it only allows vegetables with extremely low sugar levels (see “
Vegetables You Can and Cannot Eat
”). Carbohydrates make a comeback during the Consolidation phase, but it is only during the final Stabilization phase, 6 days out of 7, that total restriction is lifted.

Fats are the absolute enemy of anyone trying to be slim, as they represent the most concentrated form in which surplus energy is stored. Eating fats means you are eating an animal’s energy reserves, which, in theory as in practice, improve your chances of increasing your weight.

Since the Atkins Diet appeared, opening the way for eating immoderate amounts of fat by demonizing carbohydrates, many diets have adopted this point of view. However, this approach was quite clearly a major mistake for two reasons: (1) cholesterol and triglyceride levels rise dangerously; (2) mistrust of fats is gone, and once gone it makes any form of stabilization impossible.

There are two major sources of fats: animal and vegetable. Animal fat, found in a virtually pure state in lard, is very much present in pork products such as pâtés, salamis, sausages, hot dogs, and meat spreads. Lamb and mutton and certain poultry, such as goose and duck, have a plentiful supply. Beef is not as fatty, especially those cuts that can be grilled. Only ribs and the rib eye are really rich in fat. Butter, which comes from the creamy top of milk, is practically a pure fat. The fat content of heavy cream is around 36 percent.

The five fish with the most fat, easily recognizable by their rich taste and blue skin, are sardines, tuna, salmon, mackerel, and herring. But
remember that these fish are no fattier than ordinary steak, and the fat of coldwater fish is rich in omega-3 fatty acids, a known safeguard against cardiovascular disease.

Vegetable fats are, for the most part, represented by the long list of plant and nut oils and fruits such as avocado. Oil is even fattier than butter. Although some oils like olive, canola, or sunflower oils have nutritional qualities that have been proved to protect the heart and arteries, they all have the same caloric value and should be banned from any weight loss diet, avoided during the Consolidation phase, and eaten sparingly during the final Stabilization phase. Peanuts, walnuts, hazelnuts, pistachios, and macadamia nuts are snacks that are often eaten with a cocktail; their combination with alcohol greatly increases the calorie intake of the meal to follow.

For those who want to be slim, and in particular for those who are trying to lose weight, fats represent every danger possible.

• Fats contain, by far, the most calories—9 calories per gram (more than double the calories in carbohydrates, which provide only 4 calories per gram).
  
• Fats are very rich foods and so are rarely eaten alone. Oil, butter, and heavy cream are often associated with bread, starch, pasta, or salad dressings; the combination increases the overall calorie count considerably.
  
• Fats are not assimilated as quickly as fast sugars, but they are assimilated far more quickly than proteins, and thus their comparative energy contribution increases accordingly.
  
• Fatty foods reduce our appetite only moderately, and snacking on them, rather than on proteins, does not reduce your desire for a large meal afterward or delay the time before you next feel hungry.
  
• Finally, animal fats with high amounts of fatty acids—butter, sausages, dried meats, and fatty cheeses—pose a potential threat to the heart. For this reason, they cannot be consumed without restriction, as has been the case with the Atkins Diet and other regimes inspired by it.
  

Proteins are the third universal food group. The foods richest in proteins come from the animal kingdom. Their most abundant source is meat.

Among animal meat, beef is especially high in protein. The leaner cuts are extremely low in fat, but just as rich in protein. Mutton and lamb are visibly more marbled, and this fat reduces their protein content. Finally, some cuts of pork, which are even fattier, are not rich enough in protein to belong to the elite group of protein foods.

Organ meats like liver, kidneys, tongue, sweetbreads, chicken hearts, and tripe are very rich in protein and low in fat and carbohydrates. However, liver contains a small dose of sugar.

Poultry, with the exception of domestic goose and duck, is a relatively lean meat very rich in protein, especially turkey and chicken breast.

Fish, particularly lean white-fleshed fish like sole, skate, cod, sea bass, or tilapia are a gold mine of proteins with a very high nutritional value. Coldwater fish such as salmon, tuna, sardines, and mackerel have fattier flesh, which slightly reduces their protein content, but they nevertheless remain excellent sources of protein and greatly promote cardiovascular health.

Shellfish and other types of seafood are lean and carbohydrate-free, and rich in protein. Some, like shrimp and scallops, are often not allowed on weight loss diets because of their high cholesterol level, but that substance is concentrated in the “coral” (eggs or ovaries) of the animal’s head and not its flesh, which means that you can eat shrimp, crab, and lobster without restriction as long as you take the precaution of removing the coral first.

Eggs are an interesting source of protein. The yolk contains fats and enough cholesterol that should you be predisposed to high cholesterol, you should avoid excessive consumption of the yolk. On the other hand, egg white is the purest and most complete known form of protein, which gives it the status of benchmark protein, as it is used to classify all other proteins.

Plant proteins are found in most cereals and legumes, but these are far too rich in carbohydrates to be included in a diet whose effectiveness
depends on the purity of proteins. Furthermore, apart from soy, these plant proteins are desperately short of certain vital amino acids, so they cannot be used exclusively over a prolonged period of time.

So how can we be vegetarian? If it means not eating anything from an animal that has been raised and slaughtered for us to eat, but consuming eggs and dairy products, this is sufficient for people who are not trying to lose weight. If vegetarian means eating only vegetables, my diet becomes very hard to follow, as there is no other choice but to use incomplete vegetable proteins that have to be very cleverly teamed up with cereals and legumes to ensure that all amino acids are consumed, because without all amino acids, it is impossible for the body to produce vital proteins.

It is important to realize that humans emerged from their animal condition by becoming carnivorous. Our apelike ancestors, like today’s great anthropoid apes, were essentially vegetarians, even if, occasionally, certain apes hunted other animals for food. Indeed, it was by becoming group hunters and meat eaters that humans were able to acquire uniquely human faculties. The human body possesses a whole system for digestion and elimination that still allows us today to eat unlimited quantities of meat and fish.

We are designed to eat meat, fish, and poultry, as far as both our metabolism and psychology are concerned. Yes, it is possible to live without hunting and without eating meat, but by doing so we give up a part of what our nature expects, and we lessen the emotional effect our body is programmed to produce when we give it what it expects. What I am saying to you here may seem trivial, but it is absolutely crucial, as the purpose of any living creature, whether animal or human, is to live in such a way that what it does fits with why it has been made that way.

Of all the food categories, the digestion of proteins is the most time consuming. It takes over three hours to break down and assimilate proteins.
The reason for this is simple: protein molecules are long chains with well-soldered links, and to break down their resistance requires the combination of good chewing and the simultaneous attack of various gastric, pancreatic, and biliary juices.

This long process of calorie extraction taxes the system; it has been calculated that to obtain 100 calories from a protein food, the system must use 30 calories. We can say that the specific dynamic action of proteins is 30 percent, while it is only 12 percent for fats and just 7 percent for carbohydrates.

What we should remember from this is that when someone wanting to lose weight consumes meat, fish, or nonfat yogurt, the person has to work hard to simply digest and assimilate the food, and the calories they use doing this reduces the energy absorbed from the meal. This really works in the favor of anyone wanting to lose weight. We will explore this process at greater length when we explain how the pure protein diet works. What is more, this slow rate of digestion and assimilation delays the process of emptying the stomach and increases our sense of “feeling full” and our sense of satisfaction.

Of the three universal food groups, only proteins are indispensable for our existence. Carbohydrates are the least necessary nutrient, because our bodies can produce glucose—that is, sugar—from meat or fat. When we are deprived of food or are dieting, we draw upon our fat reserves, transforming them into the glucose that is vital for our muscles and brain. The same goes for fats: an overweight person is expert in both making and storing them.

On the other hand, we do not have the metabolic means to synthesize proteins. Just being alive and ensuring that our muscular system is maintained, that our red blood cells are renewed, that wounds heal, that hair grows, and even that memory functions—all these vital operations require proteins, a minimum of 1 gram per day for every 2 pounds of body weight.

Whenever there is not enough protein, the body is forced to draw
upon its reserves, mainly the muscles, but it also uses skin or even bones. This is what happens when unreasonable diets are followed, such as juice fasts or the Beverly Hills Diet, which allows unlimited quantities of exotic fruits.

Recently, some diets have led people to believe that our bodies can be detoxified by eating just fruit and vegetables for a few days. When you realize it has been scientifically proved that after eight hours without good-quality proteins, the body has to draw upon its own muscle reserves to ensure its vital functions, you can understand just how inappropriate such ideas are.

Anyone wanting to lose weight should therefore realize that however restrictive the diet, it should never supply the body with less than 1 gram of protein per day for every 2 pounds of body weight, and, most important, protein intake should be evenly distributed over the day’s three meals. A meager breakfast, lunch consisting of a pastry and a bar of chocolate, then pizza for dinner with fruit for dessert are all meals that lack protein and will make your skin dull and impair your body’s general strength.

A gram of protein provides only 4 calories, the same as sugar but half of what fat provides.

Only 50 percent of all meat, fish, and other food proteins are assimilated; the rest is waste or useless tissue. This means that 4 ounces of turkey or steak provide only 200 calories. When you take into account that your body has to contribute 30 percent of this caloric value—that is, 60 calories—just to assimilate it, only 140 calories are left from this tasty and filling food, the equivalent of 1 tablespoon of the dressing you deem so harmless when you add it to your salad.

A high-protein diet has two drawbacks:

• Protein is expensive
  . The cost of protein is relatively high—meat, fish, and seafood can easily make a dent in a modest budget. Eggs, poultry, and offal, like chicken livers, are more
  affordable but are still expensive. Fortunately, nonfat dairy products make it possible to get excellent quality protein at a price that allows us to offset the high cost of protein meals.
  
• Protein produces waste products that must be eliminated
  . When protein is digested, waste products, such as uric acid, remain in the system and have to be eliminated. In theory, eating higher amounts of protein foods would increase the amount of waste products and cause discomfort to certain people. In fact, the human organs, and particularly the kidneys, have mechanisms for elimination and are perfectly suited to this task. But for the kidneys to work efficiently, it is absolutely necessary that they have an increased quantity of water. The kidneys will filter and remove uric acid from our blood, provided that we increase our normal consumption of water.