The Atkins and Dukan diets

Cutting down on the body’s natural fuel to lose weight

Starch is the body’s main source of energy, both in traditional diets as well as in those recommended by the various public health bodies, including the World Health Organization (WHO), which make recommendations for a balanced diet. Robert Atkins intended to provide a diet that would lead to significant weight loss. As such, from 1972, he suggested drastically cutting down on this energy resource and replacing it with either protein or fat. Without any carbohydrate intake, the body would use the energy stored in its tissues, mainly in the form of lipids, leading to fat loss and therefore weight loss. The Atkins diet is therefore a high-protein and potentially high-fat diet that cuts out cereals, starch, fruit, sugary and dairy products, while promoting the consumption of unlimited quantities of meat, fish, eggs, animal and vegetable fat, cheese and vegetables. There are also no calorie restrictions. This diet consists of four phases, starting with the most drastic restriction of sugar, starch, pulses, fruit, milk and yoghurt, and ending with a partial reintroduction of cereals, fruit and dairy products. The initial version of the Atkins diet implicitly allowed the consumption of animal fat in large amounts. This led to people considering it as a high-fat diet that could increase the risk of developing cardiovascular diseases. The Atkins diet is probably one of the most thoroughly studied diets to date. Although it results in weight loss over the short to medium term, primarily due to water loss, the longer-term results (ranging from a few months to several years) are more mixed and many people who give up the diet tend to regain their initial weight, or even exceed it.

In the year 2000, Doctor Dukan proposed an equally low-carbohydrate, high-protein diet, that also encouraged taking particular care to avoid consuming too much fat. For practical reasons, he based the diet on 100 foodstuffs including 72 proteins and 28 vegetables, and recommended eating oat bran for its high fibre content and ability to keep dieters feeling satiated. This protein-based diet cuts out all high-sugar food during an attack phase varying from one week to two months, and requires dieters to eat low-fat, high-protein food. Sweet food such as fruit, sweet vegetables, bread, pasta and rice, are sparingly reintroduced during the stabilisation phase.

One of the advantages of consuming protein is that it is more filling than a portion of starch with the same amount of calories, and, a fortiori, more filling than simple sugars. Diets that promote protein consumption at the expense of sugar and starch are supposedly more effective in maintaining a calorie deficit and therefore bringing about weight loss. While people already suffering from kidney deficiencies are urged to avoid such diets, high-protein consumption apparently does not cause kidney malfunction among people in good health. However, such diets also place other restrictions on the consumption of cereals and pulses, sources of micronutrients and dietary fibre that are particularly useful for maintaining effective intestinal flora.

While Atkins’ and Dukan’s high-protein and low-carbohydrate diets may be effective for weight loss over the short and medium term, similar diets known as ketogenic diets are currently being studied as part of medical research into epilepsy, and are showing encouraging results. However, it is important to remember that this research has clearly defined clinical aims focusing on an approach that weighs up risks and benefits in the interests of patient health. As such, the results of the research are not directly applicable to the healthy population as a whole. Based on what we know today, the medical and scientific profession recommends that, in order to lose weight and stay in good health, we follow the public health organisations’ nutritional guidelines and eat a varied, balanced diet without cutting out any nutrient group in the long term.