The Dukan Diet

Medically Reviewed by Christine Mikstas, RD, LD on August 01, 2024
14 min read

Most people who lose weight regain more than half of it within 2 years and gain back nearly all of it within 5 years. The Dukan diet is a high-protein, very low-carbohydrate eating plan that promises to help you lose weight and "keep it off forever."

This diet was created in 2000 by French doctor and nutritionist Pierre Dukan. It's a four-step plan that cuts carbohydrates and fat and boosts protein to supposedly promote long-term weight loss. In the first phases, you're limited to 100 foods, but you can eat as much of them as you'd like.

The first two phases of the Dukan diet promote weight loss with a high-protein, no-carb diet. Eating this way puts your body into a state of ketosis, where you burn fat for energy instead of carbohydrates. In the third phase, the goal is to maintain the weight loss while slowly reintroducing some of the foods you cut. Phase four aims to keep the weight off long-term with a generally healthy diet that includes one all-protein day each week.

The Dukan diet is basically an elimination diet. It cuts certain carbs to promote weight loss.

This is how the Dukan diet claims to work, but everyone responds differently to diet plans. Even the diet's website includes the disclaimer, "Results may vary for each person."

The Dukan diet's claims are not backed by WebMD. Talk to your doctor before you start any new diet to make sure that it's safe for you.

The first phase of the diet is only protein. You may want to clear your fridge and pantry of carbs to resist the temptation. Shop for protein-based foods such as:

  • Chicken and other poultry
  • Lean beef
  • Fish and shellfish
  • Fat-free milk and other dairy products
  • Eggs
  • Tofu and tempeh
  • Sugar-free gelatin

Also, get oat bran to supply you with fiber and carbs.

So that you don't have to run to the store again in a few days, you might also want to have vegetables in your fridge for the next phase of the diet. You can include a variety of non-starchy vegetables such as broccoli, carrots, onion, tomato, kale, and mushrooms.

The first two phases of the Dukan diet are based on elimination. Your food options during these periods are very limited. As the diet progresses, you can add in more food groups.

Foods allowed on the Dukan diet

Which foods you're allowed to eat depends on the phase you're in. For the first few days, you can only eat animal proteins, sugar-free gelatin, and oat bran. Then, you can add non-starchy vegetables until you reach your weight-loss goal.

The third phase allows fruit, whole-grain bread, and cheese. Plus, you get one to two "celebration meals" where you can choose what you want to eat. In the last phase, no foods are off the table, but once a week you eat only protein.

Sugar-free gum, artificial sweeteners, spices, and unsweetened coffee and tea are also OK. As for alcohol, you can have a glass of wine per day during the consolidation and stabilization phases.

Foods to avoid on the Dukan diet

In the first phase, you'll cut everything from your diet except protein. That means no starches such as bread and white rice. They're off-limits until the third phase. So are desserts. In the final phase, you can pretty much eat what you want, except for 1 day a week when you eat nothing but protein. But to maintain weight loss, you're not supposed to go back to old habits such as eating fast food and sweets.

Dukan diet attack phase

This first phase is meant to jump-start weight loss. It's also the most restrictive phase because you can only eat 68 animal proteins, although you can eat as much of them as you want.

How long you stay in the attack phase depends on how much weight you want to lose:

  • Less than 10 pounds: 1 or 2 days
  • 15 to 30 pounds: 3 to 5 days
  • More than 40 pounds: Up to 7 days (but check with your doctor before you stay on the diet for this long)

It's recommended that you eat 1.5 tablespoons of oat bran each day for fiber and carbs and drink at least six cups of water daily to stay hydrated. Exercise every day, ideally in the morning.

Dukan diet cruise phase

In this phase, you'll continue to lose weight steadily until you reach your goal weight, which Dukan calls your "true weight." The goal is to lose 1 pound every 3 days. How long this takes depends on your current weight and your goal weight.

The cruise phase adds 32 non-starchy vegetables to the 68 animal proteins, for a total of 100 allowed foods. You alternate between all-protein days and protein-plus-vegetables days. Continue to eat oat bran. Increase your daily walks to 30 minutes to boost weight loss.

Dukan diet consolidation phase

The third phase, consolidation, is when you stick to your goal weight. It lasts 5 days for every pound you've lost. If you've dropped 10 pounds, you'll be in this phase for 50 days (about 2 months).

You can still eat all 100 foods from the cruise phase in unlimited amounts. Plus, you can have limited amounts of lamb and roast pork, some starchy foods such as bread and rice, hard cheeses, whole-grain bread, and fruit. You can also add one or two celebration meals per week with an appetizer, entrée, dessert, and a glass of wine.

Every Thursday, you eat animal protein only. This protein day helps maintain weight loss. Exercise by taking 25-minute fast walks every day.

Dukan diet stabilization phase

This last phase is designed to maintain the weight loss long-term. You can eat whatever you like, except for 1 day a week when you follow the all-protein rules from the diet's attack phase. In this phase, you also eat 3 tablespoons of oat bran a day and take the stairs whenever possible.

In the attack phase, you can eat protein-based foods, such as:

  • Poultry: Chicken, fat-free turkey sausage, and deli chicken or turkey
  • Lean meat: Beef tenderloin, sirloin, extra-lean ham, extra-lean hot dogs, lean pork chops, veal chops
  • Fish: Arctic char, cod, flounder, haddock, halibut, mackerel, salmon, tilapia, tuna
  • Shellfish: Clams, crab, lobster, mussels, octopus, oysters, scallops, shrimp
  • Vegetarian proteins: Tempeh, tofu, veggie burgers
  • Fat-free dairy: Fat-free cottage cheese, cream cheese, milk, Greek yogurt, ricotta, sour cream
  • Eggs

You can also eat:

  • Sugar-free gelatin
  • Oat bran
  • Goji berries
  • Shirataki, a noodle alternative made from the Konjac root from Asia

During the cruise phase, you add these non-starchy vegetables:

  • Artichokes
  • Cruciferous vegetables such as broccoli, Brussels sprouts, and cauliflower
  • Greens such as arugula, lettuce, kale, spinach, and watercress
  • Colorful vegetables such as beets, carrots, squash, tomatoes, and peppers
  • Mushrooms
  • Onion, leeks, and shallots

You can also use olive oil.

The consolidation phase adds:

  • Starchy foods such as bread, rice, and cereal 
  • Hard cheese such as Gruyère, parmesan, or pecorino
  • Whole-grain bread
  • Fruits (except for bananas, cherries, figs, and grapes)

Every diet has pros and cons. Some have more pros than others. And some diets fit better into one person's lifestyle than another's.

Benefits of the Dukan diet

The goals of the Dukan diet are to help you lose weight and maintain that weight loss long-term. It's hard to know whether this diet really helps with long-term weight loss because there hasn't been much research done on it. In one small study, women lost an average of 33 pounds after 8-10 weeks on this diet.

One benefit of the Dukan diet is that you don't have to count calories. You can eat as much as you want, as long as you only eat approved foods. You shouldn't feel hungry because of all the protein in the diet, and lean proteins and vegetables may help improve heart health, blood sugar, and inflammation.

The Dukan diet also includes exercise. The activities it recommends are easy for most people to do, such as walking and stair climbing.

Risks of the Dukan diet

The Dukan diet is very restrictive. In the first two phases, you have to cut out most food groups, possibly for months. Very restrictive diets can be hard to stick with. And by cutting out fruits and vegetables, you lose important nutrients such as vitamin C and folate.

This is a complicated diet because there are so many rules to follow. It's hard to shop for food and plan meals when you can only eat certain foods on certain days.

You might not feel good when you start on this diet. The lack of carbs could make you more tired than usual. You need carbs for energy.

Putting your body into ketosis can cause side effects such as nausea, vomiting, tiredness, and diarrhea. These problems should go away in a few days or weeks as your body gets used to the diet. Ketosis can also dehydrate you because your kidneys remove more fluid.

The huge amount of protein in this diet can pose health risks. Your kidneys have to filter out the extra protein, which could overload and damage them. Extra protein boosts levels of an amino acid called homocysteine in the blood. High homocysteine levels are linked to blood vessel damage and heart disease. Excess protein also increases the risk for osteoporosis.

This diet isn't safe for people with diabetes. Cutting carbs could make your blood sugar harder to control.

Level of effort: Medium

Prepping your food shouldn't be a problem, and you don't need exotic ingredients. But you will be pretty restricted in what you can eat at the start of the diet. And you'll have to keep up with the changing list of rules in each phase.

  • Level of limitations: Eating mainly protein and oat bran can get tiresome.

  • Cooking and shopping: The limited list of ingredients might make shopping easier at first, but you'll have to adapt to the shifting rules in each phase. 

  • Packaged foods or meals: None required.

  • In-person meetings: No.

  • Exercise: A daily 20- to 30-minute walk is essential to the plan.

Does it allow for dietary restrictions or preferences?

Vegetarian or vegan. This diet is based on eating a lot of lean meat, poultry, fish, shellfish, fat-free dairy, and eggs. Seitan, tempeh, and tofu are the veggie protein options available -- beans, nuts, and lentils aren't on the diet's list of allowed foods. On days when all you eat is protein, things can get boring quickly if you don't eat meat.

Low-fat diet. If you're already following a low-fat diet or have a heart condition that requires you to eat ultra-low-fat foods, this diet might fit like a glove. The allowed foods — mainly protein, veggies, and fruit — are lean, low-fat, or no-fat.

Gluten-free. The earlier phases of the diet may work for a gluten-free diet, but as the rules relax, it's not strictly gluten-free. If you're trying to avoid gluten completely, make it a habit to read food labels carefully.

What else you should know

Costs. None beyond your shopping, unless you sign up for online coaching, which is optional. The cost varies depending on how much weight you'd like to lose.

Support. There's a strong community aspect to this plan. The official website offers sample recipes, inspirational success stories from real people, and coaches to help guide dieters through each phase.

You may lose weight at first on the Dukan diet, but registered dietitian nutritionist Kathleen Zelman, MPH, RD, LD, notes that the diet may be too expensive and restrictive to maintain in the long term. "The rules of this diet are complicated -- and potentially frustrating," warns Zelman.

Does the Dukan diet work?

The first stages of this diet will likely result in significant weight loss due to the few carbohydrates allowed on the plan. But when you go back to eating normally after reaching your goal weight, you may gain some of this weight back.

Zelman points out that one study has shown the Dukan diet may help you lose belly fat in the short term, but the evidence supporting the diet is limited.

In general, research shows that high-protein diets are effective for weight loss, but experts still do not know what the long-term effects are for your health and weight. And there is no evidence that having one all-protein day, along with exercise, is enough to maintain your weight loss.

Is it good for certain conditions?

Although the diet can lead to weight loss in the short term, which can help with certain health conditions, the risks may outweigh the benefits.

If you’re on medication for diabetes, you will likely need to change your dose, because the first two stages are very low in carbohydrates. If you have renal disease, you might get more protein than your kidneys can handle. And if you have heart disease or a digestive disorder, you would be missing out on heart-healthy fiber. Talk with your doctor if you are planning to start the Dukan diet.

Who shouldn’t try the Dukan diet?

If you have chronic conditions such as gout, kidney disease, or liver disease, Zelman recommends steering clear of the Dukan diet, as the diet doesn't follow the recommended dietary guidelines for those conditions.

Older adults at risk for muscle loss should talk with their doctor before they start the Dukan diet, which can be a side effect of rapid weight loss.

If you often experience digestive issues or constipation, the Dukan diet may not be the right fit for you, as it provides limited sources of fiber. Zelman notes that gut health is important for your whole body, including your brain health, but you probably won't get enough fiber from solely oat bran. "Oat bran isn't particularly high in fiber," says Zelman. "The Dukan diet recommends 1.5 tablespoons daily, which has 2 grams of fiber, but most people need closer to 28 grams daily." Cutting out foods such as fruits, vegetables, and beans can negatively affect your gut health and may make your stomach problems worse.

Because of the restrictive nature of this plan, it's important to check with your doctor first if you have a health condition. Zelman cautions that children should never be put on the Dukan diet, as the restrictiveness of the diet can lead to nutritional gaps that can affect their growth and development.

And remember: animal protein is expensive. The grocery bill for this diet may put it out of reach if you're on a budget.

The final word

Unlike other high-protein diets, this plan focuses on lean protein sources over those high in saturated fat. And protein can make you feel fuller longer, helping you lose weight.

The downside is that this plan often isn't sustainable. Even more problematic, it recommends that you stay in the consolidation phase until you reach your goal. If you have a lot of weight to lose, this phase could go on for months or even years, which could lead to a nutritionally inadequate diet -- if you're able to sustain the diet at all. Even if you lose a lot of weight on the Dukan diet, the pounds often come back because the restrictive nature of the plan makes it hard to maintain.

If you’re looking to lose a relatively small amount of weight fast, then this diet may work for you. If you are over 50, have a health condition such as diabetes, or need to lose a lot of weight, talk to your doctor before you try out the diet.

While one small study suggests the benefits of this diet, Zelman doesn't recommend it. Instead, she suggests others that have wider support from the medical community: "The Mediterranean diet is a strong, evidence-based plan that we've seen -- over and over again -- has mountains of studies on it."

Use these sample diets as a guide to each phase of the plan:

Attack phase

  • Breakfast: Scrambled eggs, skim milk, fat-free plain Greek yogurt

  • Lunch: Grilled chicken breast with fat-free ricotta cheese

  • Dinner: Sauteed shrimp and scallops

Cruise phase

  • Breakfast: Omelet with spinach, tomatoes, and red peppers

  • Lunch: Vegetarian burger with fat-free cottage cheese

  • Dinner: Pork tenderloin with grilled asparagus

Consolidation phase

  • Breakfast: Poached egg with whole-grain toast and strawberries

  • Lunch: Grilled chicken salad with low-fat dressing

  • Dinner: Sirloin steak with baked potato and zucchini

There are many online sources of good Dukan diet recipes. Here are a few ideas to try, by phase.

Dukan diet phase 1 recipes

  • Scrambled eggs with cream cheese and chives. Scramble egg whites with 1 tablespoon each of fat-free cream cheese and chives.
  • Steamed Cajun shrimp. Boil shrimp in water, lemon juice, and Old Bay seasoning for 4-6 minutes until the shrimp are cooked through.
  • Turkey meatloaf. Mix chopped onion, two beaten eggs, fat-free yogurt, oat bran, and minced turkey together. Form the mixture into a loaf and bake until fully cooked.

Dukan diet phase 2 recipes

  • Oat bran porridge. Mix oat bran with skim milk. Add vanilla extract and Stevia for sweetness. Heat in the microwave for 1 minute. Stir and let the mixture soak. Then, heat in the microwave for another 30 seconds.
  • Tuna patties. Mix one can (in water) of tuna, an egg, oat bran, chives, salt, and pepper into patties. Fry in a pan for about 3-4 minutes each side.
  • Seitan stir-fry. Cook seitan in a wok or frying pan with bell peppers, carrots, diced onion, ginger, mushroom, and leek. Add soy sauce to taste.

Dukan diet phase 3 recipes

  • Blueberry kale smoothie. Blend frozen blueberries, kale, nonfat vanilla Greek yogurt, almond butter, and ice until smooth.
  • Turkey salad. Make a bed of raw spinach, grape tomatoes, baby carrots, chopped tomatoes, and artichoke hearts. Top with chopped turkey and Greek yogurt dressing.
  • Chicken curry. Cut skinless chicken breasts into small pieces. Mix fat-free sour cream, lime juice, and tandoori powder in a bowl. Coat the chicken in the mixture. Saute the chicken mixture with onion, canned tomatoes, and garlic.

Dukan diet phase 4 recipes

  • Cottage cheese pancakes. Mix eggs, baking soda, flour, cottage cheese, and salt. Spoon the mixture onto a heated pan and cook the pancakes until browned.
  • Broccoli bake. Boil or steam broccoli until it is soft. Place it in a baking dish and cover with low-fat mozzarella cheese and low-fat bacon. Season to taste and bake until browned on top.
  • Taco stir-fry. Cook onions and garlic in a pan until soft. Add minced beef tenderloin and cook until browned. Add chili powder, cayenne pepper, and cumin, plus 1/3 cup water. Cook, stirring often, until the water is absorbed. Serve with a dollop of fat-free sour cream on top.

Is the Dukan diet healthy?

That's hard to know because there hasn't been much research on the diet. The early phases are so restrictive that they could lead to nutrient deficiencies. And the excess protein could increase the risk for kidney damage, heart disease, and osteoporosis.

How fast can I lose weight on the Dukan diet?

In one study, women lost an average of 33 pounds after 8-10 weeks on this diet.

How many eggs can you eat on the Dukan diet?

There's no limit to how much you can eat, and eggs are included in every phase of the diet. You can eat chicken, quail, or duck eggs.

Does the Dukan diet put you in ketosis?

In the early phases, the diet puts your body into ketosis. That means you burn fat for energy instead of carbohydrates.