The Dukan diet is a high protein, low carbohydrate eating plan designed by Pierre Dukan, a former French physician and self-proclaimed nutritionist.
Also called the Dukan method, this diet is based on how hunter-gatherers may have eaten.
The diet includes 100 foods, and all are either proteins or vegetables. A person can eat as much as they like, as long as they only eat those 100 foods.
The Dukan diet may contribute to weight loss, but research has linked it to possible health complications, including kidney disease and liver disease. Also, it may not provide the full range of nutrients the body needs.
This article provides a review of the Dukan diet, including its method, if it works, and some possible health risks.
The Dukan diet requires a person to eat high protein foods and reduce their intake of carbs and fats. It focuses on natural rather than packaged foods, and it encourages daily physical activity.
The official Dukan diet website provides a list of the 100 foods allowed on the diet. Of the 100 foods, 68 are “pure proteins” and 32 are vegetables. A person can introduce additional foods during the later stages of the diet.
The Dukan diet is based on the theory that eating a lot of protein can help people lose weight. This is because:
- lean, high protein foods tend to be lower in calories
- eating protein can help people feel full
- digesting protein uses more energy, so the body burns a few more calories
Restricting carbs and fats induces a starvation-like state, which forces the body to use fat stores for energy, similar to the Atkin’s diet.
There are four phases in the Dukan diet:
The attack phase
The attack phase consists of eating foods from the “pure protein” list. It aims for rapid weight loss.
The theory is that eating a high quantity of protein-rich foods will kick-start the metabolism. However, although it takes a few more calories to digest protein, dietitians agree that no particular foods can kick-start the metabolism. Exercise can boost it, however.
People might lose weight in this phase because cutting back on carbs removes water from the body, and this water loss plus dehydration might lead to rapid weight loss.
The attack phase usually lasts for around 2–5 days, but people aiming to lose more than 40 pounds might stay in this phase for longer than 7 days.
During this phase, a person can eat any of the 68 pure proteins listed. These are all lean protein sources and include lean beef, fish, chicken, eggs, soy, cottage cheese, and fat-free dairy. Choices should be low in fat and contain no added sugars. A person can eat as much as they want, and there is no calorie counting.
The diet also requires them to eat at least 1.5 tablespoons (tbsp) of oat bran each day. Oat bran is very high in fiber, so the body cannot break down or digest most of this carb. High fiber foods help suppress hunger.
During the attack phase, the diet requires a person to drink at least 1.5 liters (l) of water and exercise for 20 minutes each day.
The cruise phase
The cruise phase aims to lower a person’s body weight gradually by adding 32 specific vegetables to the diet. People can now eat all 100 food items on the list, though they should try to alternate between pure protein days and protein plus vegetable days.
The length of this phase will depend on how much weight the person wants to lose. It lasts for 3 days for every pound they want to lose.
A person can eat unlimited amounts of low fat proteins and unlimited amounts of nonstarchy vegetables, including spinach, okra, lettuce, and green beans.
In the cruise phase, the diet requires them to eat 2 tbsp of oat bran and exercise for 30–60 minutes each day.
The consolidation phase
In the consolidation phase, the aim is not to lose weight, but to avoid regaining it. A person is allowed to introduce some starchy foods. Every day, they can now eat:
- unlimited quantities of protein and vegetables
- one piece of fruit
- 1.5 ounces of hard-rind cheese
- two slices of whole grain bread
They can also have one or two servings of starchy food and one or two celebration meals each week. In a celebration meal, a person can eat whatever they want.
This phase requires them to eat the core diet of pure protein one day each week, preferably on the same day of each week.
This phase requires 25 minutes of exercise per day.
The stabilization phase
The stabilization phase is the long-term maintenance part of the plan. The person should not expect to lose or gain weight during this time.
One day each week, they will have an all-protein day, as in the attack phase. Apart from that, they can eat whatever they want, as long as they follow some simple rules:
- Eat 3 tbsp of oat bran each day.
- Take the stairs as often as possible.
- Have a “pure protein day” each Thursday.
- Exercise for 20 minutes each day.
- Continue to drink 1.5 l of water daily.
The stabilization phase is a long-term plan that becomes part of the person’s lifestyle.
At this point, people can consume artificial sweeteners, vinegars, sugar-free gum, and spices. The diet also recommends taking multivitamins with minerals.
Following a high protein diet may lead to weight loss, but research has not proven that this is healthy weight loss.
According to a 2014 study, high protein diets may promote weight loss for a number of reasons, including:
- helping the person feel more full
- reducing the levels of a hunger hormone called ghrelin
- improving the balance of glucose in the body
- causing diuresis, or a loss of body fluids
However, researchers have noted that the diet limits certain food groups, such as grains and fruits, which means that it is not nutritionally complete.
It can also be a difficult and inconvenient diet, as it requires a person to prepare all meals from scratch. Eating out is possible, but it may be difficult to control the food preparation methods in a restaurant.
The Dukan diet has many rules that may make it difficult to maintain, especially if there are others in the household who are not following the diet.
Other problems include the following:
- The initial weight loss will mainly be water, which is temporary.
- Lean protein, such as meat and fish, can be expensive.
- The rules are strict, so it can be hard to follow long term.
So far, research has not proven that high protein diets are a healthful approach to weight loss.
According to health experts in the United Kingdom, the Dukan diet “isn’t nutritionally balanced,” and “there’s a danger [that] this type of diet could increase [the] risk of long-term health problems if [people] don’t stick to the rules.”
The 2014 study reports that eating lots of protein, in combination with a Western diet, could increase the risk of metabolic disease. High protein diets can also place the kidneys under stress due to the need to eliminate waste produced in the digestion of protein.
One 2015 study states that following the Dukan diet long term can pose health risks, including:
- kidney disease
- liver disease
- cardiovascular disease
The Dukan diet website explains that there are some similarities between the Dukan diet and the Atkin’s diet, as they both involve reducing carbs.
However, there are some key differences:
- In the Dukan diet, people do not need to count calories, carbs, or other nutritional values.
- The Dukan diet offers a list of 100 foods, plus some other items in the last phase, whereas the Atkin’s diet is more restrictive.
- The Dukan diet concentrates on low fat protein, including fat-free dairy products, whereas the Atkin’s diet has no limits on dairy fats, meat fats, or any saturated fats.
- The Atkin’s diet recommends shakes, bars, and other packaged foods, whereas the Dukan diet emphasizes 100 natural foods.
The Dukan diet is a high protein, low carb diet. Though it may help people lose weight, research has linked the diet to several possible health complications. Also, any weight loss may actually be a result of the daily exercise the diet requires.
A person should speak to a doctor or nutritionist before making any significant changes to their diet. These healthcare professionals can recommend healthful ways to lose weight.