Dangers of the Dukan Diet

Jennifer O'Donnell-Giles | September 15, 2016

New diets and diet crazes are everywhere these days. Few of them are healthy and are based on science, while others are money-making schemes. And some are just downright dangerous. The Dukan diet is one of those dangerous ones that can wreak havoc on your body and should be avoided.

The Dukan diet recently gained popularity due to celebrity endorsements. It was developed in 2000 by a French doctor, Pierre Dukan, but there’s no science-based evidence that it supports optimal health or long term weight loss. This strict diet limits many foods and severely lacks a balance of nutrients. It’s high in protein but low in healthy fats, cholesterol, and carbohydrates that our bodies actually need. The Dukan diet is broken up into four phases: the Attack Phase, the Cruise Phase, the Consolidation Phase, and the Stabilization Phase.

  1. Attack Phase: Unlimited protein is allowed, along with 1.5 tablespoons of oat bran and 6 cups of water. This phase lasts 5 to 10 days and is supposed to yield approximately 7 pounds of weight loss.
  2. Cruise Phase: This phase cycles between 5 days of eating only protein and 5 days of protein with non-starchy vegetables and 2 Tbsp oat bran until a goal weight is achieved. Expected weight loss is a pound every 3 days during this phase.
  3. Consolidation Phase: Some fruits and grains are allowed, specifically one piece of low sugar fruit, two slices of whole grain bread, 2 Tbsp oat bran, and one ounce of hard cheese every day. Dieters are also allowed one cheat meal a week, but they have to go back and complete one day of the Attack Phase regulations once a week, as well.
  4. Stabilization Phase: This is a maintenance plan for the rest of the dieters’ lives. It basically consists of regular eating with the inclusion of 3 tablespoons of oat bran every day, along with exercise. However, on Thursdays, they can only consume pure protein.

A menu for a day during the Attack Phase would look like the following:

  • Breakfast: warm drink, low-fat cottage cheese, and two slices of chicken breast
  • Lunch: beef and low-fat yogurt
  • Snack: low-carb cinnamon oat bran pancake
  • Dinner: garlic tiger prawns and garlic chicken

Rapid weight loss, combined with nutrient deficiencies, does the body significantly more harm than good. Side effects of the Dukan diet may include bad breath, constipation, dry mouth and fatigue. It doesn’t meet basic human nutritional requirements, especially because it greatly cuts down on essential food groups like fruits and vegetables. The diet lacks vitamins A, B2, C and D, as well as folates, potassium and fiber. Due to the unhealthy rate of weight loss, dieters also reported loss of muscle mass. On top of all that, there are high risks of developing gallstones and regaining the weight lost during this diet.

It’s no surprise that the Dukan diet earned its label as one of the five worst diets in the world in 2011. Dangerous diets that promise quick and easy fixes to lose weight are devoid of essential nutrients and will wreak havoc on our health. By equipping people with science-based knowledge, we can avoid these unhealthy and dangerous diets and focus on maintaining a balanced whole food diet that’s paired with regular exercise to help us safely lose weight and keep it off in the long term.

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Jennifer O'Donnell-Giles

Jenn Giles, R.D., C.S.S.D. is all about health and wellness. She has over 15 years’ experience, including a dual master’s degree in Nutrition and Exercise Physiology from Columbia University. She is a Registered Dietitian (RD) and a Board Certified Specialist in Sports Dietetics (CSSD). She supplements all of this with her spin instructor certification and USATriathlon Level I Coach Certification.

Jennifer is passionate about (actually, obsessed with) the sport of triathlon. She has been personally participating in triathlons since 2000 and running road races since 1992. She is a two-time Ironman finisher and has completed countless numerous marathons. She has been a member of Power Bar Team Elite since 2006 and competed as a member of the 2006 Aquaphor/Active.com Sponsored Athlete Team. She was ranked as USAT All American Honorable mention in 2006 and 2011. Jennifer does all of this along side of her husband, Patrick, who is an equally accomplished triathlete and runner. They try as hard as they can to do all of their training and racing together.

She will tell you, however, that her most important, most rewarding and most challenging job is as a mother of four. She knows first hand the challenges of maintaining optimal fitness, overall good health and achieving goals while raising a family - of which good nutrition is the cornerstone.

Most importantly, she knows how to motivate, inspire and challenge athletes based on their own abilities, strengths and everyday lifestyles. She believes there is an athlete in everyone - no matter what their abilities are – and if those abilities are manifold, then there is an even better athlete in there!

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