The Dukan Diet and Carbohydrate Restriction in Nutrition

French general practitioner Pierre Dukan created the diet that bears his name in the 1970s, promising rapid weight loss through a high-protein, low-fat, and low-carbohydrate eating plan. This hyper-protein diet gained worldwide popularity in 2000, with the publication of The Dukan Diet in France and its subsequent translation into multiple languages.

It is important to note that this diet can sometimes cause unwanted side effects, so consulting a dietitian before starting is recommended.

Table of Contents

• What is the Dukan Diet?

• Phases of the Diet

  • Phase 1 – Attack

  • Phase 2 – Cruise

  • Phase 3 – Consolidation

  • Phase 4 – Stabilization

• Dukan Diet: Forbidden Foods

• Dukan Diet: Allowed Foods

• Benefits and Risks of the Diet

• How Carbohydrate Restriction Affects Long-Term Health

What is the Dukan Diet?

According to the diet, people who want to lose weight can consume up to 100 different foods without portion restrictions, as long as daily meals follow specific rules.

The diet focuses on consuming meat, fresh fruits, and vegetables with minimal processing and encourages an active lifestyle to enhance the effects of dietary restrictions.

Of the 100 permitted foods, 68 are pure proteins, and 32 are low-starch vegetables that can gradually be added depending on the diet phase.

Phases of the Diet

The high-protein Dukan Diet is divided into four distinct phases, based on the types of allowed foods and the desired results. The first two phases are more restrictive in terms of food variety and aim to kick-start weight loss by altering metabolism.

The last two phases are more flexible, allowing a gradual return to a more varied diet to maintain the achieved weight.

Phase 1 – Attack

The Attack phase initiates weight loss and stimulates ketosis, where the body burns fat for energy instead of carbohydrates.

Recommended foods include lean proteins from fish, eggs, low-fat dairy, 1.5 tablespoons of oat bran, and at least 1.5 liters (about 6 cups) of water per day. Artificial sweeteners, shirataki noodles, and low-carb noodles can be consumed without restriction. However, the intake of vegetable oils, lemon juice, and pickles should be limited.

This phase typically lasts 3–7 days, depending on the weight loss goal and individual progress. Moderate exercise can enhance the diet’s effects and shorten this initial phase.

Phase 2 – Cruise

The Cruise phase introduces non-starchy vegetables (from the 32 allowed types) alongside proteins, aiming for steady, gradual weight loss.

Oat bran consumption increases to 2 tablespoons per day, and small amounts of olive oil are allowed for meal preparation.

During this phase, protein-only days are alternated with protein + vegetable days (1–5 days in rotation), and weight loss averages about 1 kg every 3 days.

Phase 3 – Consolidation

The Consolidation phase helps maintain weight and prevents regaining previously lost kilos. The key rule is to have one pure protein day per week, following the Attack phase guidelines.

Daily oat bran consumption and physical activity continue, along with adequate hydration.

Phase 4 – Stabilization

The Stabilization phase focuses on long-term maintenance with three rules:

1. Consume 3 tablespoons of oat bran daily.

2. Have one protein-only day per week.

3. Walk at least 20 minutes daily.

There are no dietary restrictions in this phase, though moderate consumption of fruits and alcohol is recommended.

Dukan Diet: Forbidden Foods

The main foods to avoid include:

• Fatty meats

• Certain fruits: bananas, cherries, grapes, figs, avocado

• Full-fat dairy: milk, butter, cheese

• Potatoes

• Nuts and seeds

• Whole grains, bread, pasta, rice

• Sugar

Dukan Diet: Allowed Foods

Proteins

• Skinless poultry

• Beef, pork, and game

• Fish and seafood

• Eggs

• Low-fat dairy

• Soy products, tofu, and seitan

Daily oat bran, goji berries, and lemon juice are also recommended in moderation.

Vegetables (low-starch)

• Mushrooms, green beans, zucchini, carrots, artichokes, eggplant, onions, leeks

• Lettuce, cabbage, arugula, cucumber, fennel, tomatoes, radishes, asparagus, celery

Starchy foods (allowed once a week)

• Potatoes, dried beans, chickpeas, dried peas, rice, corn, pasta, and other cereals (except oats)

Fruits (from phase 3 onward)

• Apples, pears, peaches, nectarines, oranges, strawberries, blueberries, raspberries, apricots, mandarins, kiwi

Benefits and Risks of the Diet

The Dukan Diet is popular among those who want to lose excess weight but cannot give up meat. Its benefits include:

• Promotes satiety due to high protein intake

• Helps maintain ghrelin (the “hunger hormone”) within physiological limits

• Supports glycemic balance

However, high-protein diets have drawbacks when followed long-term:

• Protein intake exceeds recommended levels

• Limited fruit intake can lead to vitamin deficiencies

• Induced ketosis can increase the risk of nausea and vomiting

• Prolonged hyper-protein diets may cause liver, kidney, bone, or cardiovascular problems

It is not recommended for overweight individuals with chronic conditions, diabetic patients on insulin, those with severe eating disorders, pregnant or breastfeeding women. Consulting a dietitian is advised before starting.

How Carbohydrate Restriction Affects Long-Term Health

Low-carb diets can produce short-term results but may deprive the body of essential nutrients if followed long-term. They can slow metabolism, and most people regain weight after returning to normal eating.

While the Dukan Diet can be effective for rapid weight loss, it is not suitable for everyone and should be adopted carefully with professional guidance.

References

• Murphy, T. Diets That Do and Diets That Don’t: Part 4 – The Dukan Diet

• The Dukan Diet: The Revised and Updated Edition

• The Truth About the Dukan Diet

• Traditional Weight Loss and Dukan Diets: Nutritional and Laboratory Results, Journal of Food Science and Nutritional Disorders