Dissociated diet: a good idea?

Very popular in the early 90s, dissociated diets continue to appeal to candidates for weight loss. Their principle? Separate the consumption of different food groups, with the aim of limiting calorie storage and reducing energy intake. But do these diets actually work? What are their limits ? Let's do a check in.

Food dissociation: what is the principle?

Food dissociation consists of separating different food groups within the same meal, or even an entire day for some.

These diets are based on the idea that combining certain types of foods could interfere with digestion, causing the digestive system to become overloaded and even leading to increased fat storage.


There are many separate diets, depending on the categories of foods that should not be combined. The most common are based on a dissociation of foods rich in carbohydrates and foods rich in proteins and lipids . Some suggest not combining acidifying and alkalizing foods . Most recommend not mixing fruits with other foods, and therefore always eating them alone between meals. Finally, the strictest are required to consume only one type of food per day.

How does the dissociated diet work and why eat like this?

The first dissociated diet was born in the United States, in the 1930s, from its designer Dr Hay, a fan of natural medicine . According to Dr. Hay's theories, proper digestion of proteins requires a level of acidity incompatible with that of carbohydrates, which is ideally done in an alkaline environment. Foods that are sources of protein (meat, fish, eggs, cold meats, etc.) and foods that are sources of carbohydrates (starches, bread, sweet products) should therefore not be consumed within the same meal to be able to be digested correctly. When these two families of foods are consumed during the same meal, digestion risks being disrupted: as the carbohydrates are only partially digested, some of it stagnates in the intestines and ferments, causing intestinal gas. This poor digestion would promote the storage of fats , and would be the cause of an accumulation of acid residues responsible for a certain number of pathologies.

To avoid this, Dr Hay recommends 5 main rules to follow.

The dissociation of acidic and alkaline foods  : Dr Hay recommends not consuming acidifying foods (animal proteins, cereals and dairy products) and alkalizing foods (fruits and vegetables) in the same meal in order to facilitate optimal digestion and maintain the acid-base balance of the body.

Separation of carbohydrate and protein meals  : Dr. Hay recommends leaving an interval of at least 4 hours between carbohydrate meals and protein meals.

Limiting refined carbohydrates and saturated fats  : Although Dr. Hay's diet focuses primarily on food dissociation, he also recommends limiting processed foods, refined sugars, and saturated fats (butter, crème fraîche).

The emphasis on fruits, vegetables and whole grains, which should ideally represent the main energy intake.

Milk and its derivatives should not be mixed with other foods and their consumption should be as limited as possible.

Proteins, starches, fats: What foods should not be combined or mixed to lose weight?

As seen previously, Dr. Hay's dissociated diet suggests not combining acidic foods and alkaline foods in the same meal. But since then, other diets based on the dissociation of foods have emerged and been emulated. This is particularly the case for so-called “low-carb” diets which were very successful in the 90s, such as the Scarsdale and Montignac diets.

These Low-carb diets have the fundamental principle of limiting the amount of glucose in the blood by reducing the consumption of carbohydrates (simple sugars, starches, starch), with the aim of causing a reduction in insulin secretion , the hormone responsible for fat storage. Their main objective is therefore to promote the burning of fat as a source of energy.

Montignac, Antoine, Shelton: how to do the different types of dissociated diets

Montignac: the best

Imagined by Michel Montignac in the 1980s, the Montignac diet essentially focuses on the selection of foods based on their glycemic index (GI), namely the speed at which carbohydrates contained in foods raise blood sugar levels after being consumed. . This diet recommends not combining high GI foods and foods rich in lipids , based on the principle that the insulin secreted when consuming high GI foods promotes fat storage.

Unlike some diets, the Montignac diet does not focus on counting calories, but rather on the quality of foods consumed and their impact on blood sugar levels. It is a dissociated diet which does not exclude any category of food, which is based on common sense principles (limit saturated fats, encourage physical activity, favor low GI foods) and which is balanced.

Antoine: not recommended!

The principle of the Antoine dissociated diet, created by Doctor Jean-Claude Houdret, a French nutritionist, in the 1990s, is to eat only one category of food per day, for a week .
As an example, here is an example of an attack week from the Antoine diet:

  • Monday: fish only (cod, sole, shrimp, salmon, etc.)
  • Tuesday: fruit (apples, strawberries, watermelon, pear, oranges, etc.)
  • Wednesday: eggs,
  • Thursday: meats (beef, poultry, pork, etc.)
  • Friday: starchy foods (potatoes, pasta, rice, legumes, etc.)
  • Saturday: dairy products (natural yogurts, cheeses, cottage cheese, etc.)
  • Sunday: vegetables (green beans, zucchini, tomatoes, salad, cauliflower, etc.)

The official explanation is that by consuming several types of food in a single meal, the digestive system and metabolism would be slowed down, and the organs would be overworked.

In practice, this diet is mainly based on the principle of food weariness and saturation of the appetite: by eating only one food per day, we inevitably and drastically reduce the daily caloric intake, which leads to a loss of weight.

Although the risk of deficiencies is limited, because a balanced diet is not achieved over a single day but rather over the week or month, this diet risks generating intense frustration, as well as potential digestive and psychological disorders. It is also and above all a diet which drastically cuts off all social and family life, and which is therefore difficult if not impossible to follow in the long term.

Shelton: not so easy to follow

Named after the American naturopath Herbert M. Shelton who invented it, the Shelton diet is based on the principles of naturopathy, natural biology and food combinations. This diet emphasizes several main concepts, including the dissociation of protein foods and alkaline foods (namely fruits and vegetables), intermittent and prolonged fasting , a natural diet , purification and regeneration of the body through methods such as fasting, relaxation and rest. According to the Shelton diet, fruits must also be consumed alone on an empty stomach, therefore as a single food meal or at a distance from meals.

This diet does not exclude any food, apart from ultra-processed foods which are in any case not recommended either for health or for weight, and is therefore rather balanced if you take the time to follow it correctly. Its big downside  : its complexity of implementation  ! The rules are numerous, which makes spontaneous eating, social meals and long-term monitoring difficult.

How effective is it for weight loss?

The principle of food dissociation, based on a theory according to which the digestive system has difficulty efficiently processing several types of nutrients (carbohydrates and proteins), is not based on any serious scientific study. Their effectiveness in weight loss is only the consequence of the reduction in daily calorie intake, linked to the numerous rules to follow, which largely reduce the range of possible menus.

Remember that weight loss is only a reflection of the difference between caloric intake and caloric expenditure . A sharp reduction in caloric intake therefore inevitably leads to fairly rapid weight loss.

This type of diet is unsustainable in the long term, and generally leads to weariness which pushes you to suddenly abandon everything. The patient then returns to his old bad eating habits, since he has not learned to eat well.

The result is a weight gain, most often with a yo-yo effect, since the body tends to adapt to the low caloric intake imposed on it by naturally reducing its basic metabolism, and to store nutrients more quickly. kilos when stopping the diet. This is the reason why all diets that are too low-calorie , fancy diets and diets that are difficult to maintain are not recommended. To lose weight sustainably, we recommend: eating a balanced diet without excluding any food category, favoring fresh fruits and vegetables as well as whole grains, legumes and nuts and limiting ultra-processed foods as much as possible. , rich in sugars and saturated fats.