13 Day Metabolism Diet

You lose weight on the 13 Day Metabolism diet because of its calorie restriction.
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The diet industry is full of crash diets promising instant results. One program that's creating quite a buzz online is the 13-day diet. Also known as the Copenhagen Diet or Royal Danish Hospital Diet, the 13-day metabolism diet is a fad diet that makes bold claims of fast weight loss.


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The 13-Day Diet

Losing 22 pounds in less than two weeks may sound enticing, but it's certainly not realistic. That said, the 13-day diet, a program that is easy to access on the internet, promises users a weight loss of up to 22 pounds in 13 days.


The origination of this diet is unclear; however, a thorough search only results in articles written about the diet. There is no information directly from the Royal Danish Hospital or any medical experts citing studies or scientific evidence that the 13-day diet is a legitimate weight-loss program.


Although the 13-day diet lasts less than two weeks, it is very strict. A March 2018 article published in the Sun Online that featured an interview with Sarah Flower, a UK registered nutritionist, reports that the 13-day diet meal plan is well under 1,000 calories a day and is "a far cry from healthy." As far as food goes, the article lists coffee, tea, meats like steak and ham, hard-boiled eggs, limited fruits and veggies, an occasional slice of toast and low-fat yogurt.


Read more: 9 Unhealthy, Even Dangerous Weight-Loss Diets

Problem With Fad Diets

The problem with fad diets like the 13-day diet is that they act as a quick fix. Rather than teaching you how to make changes to your diet, they tell you exactly what to eat and what to avoid, and kick you off the diet if you break one rule.

While this diet may result in a short-term weight loss, the odds of maintaining that loss are not in your favor. In fact, Johns Hopkins Medicine reports that most people who experience rapid weight loss with extremely low-calorie diets regain it two to three years later.

What's more, the Cleveland Clinic points out that many fad diets lack major nutrients needed to prevent health problems later on life. Quite often, the nutrients that are not included are, dietary fiber, carbohydrates, select vitamins, minerals, and protective phytochemicals.

If you're unsure about the validity of a diet, and more specifically, the 13-day metabolism diet, the Academy of Nutrition and Dietetics says to examine the program with this in mind: If a diet or product sounds too good to be true, it probably is.

When deciding on a diet program, the Academy says to stay away from any diet that makes unrealistic claims or requires you to follow certain rules, including:

  • Claims or promises of rapid weight loss
  • Requirements for eliminating or severely limiting entire food groups or macronutrients
  • Rigid menus with little to no flexibility
  • Requirements for eating foods in specific combinations
  • Claims that you can successfully lose and keep the weight off without any exercise

Read more: The Best Way to Lose Weight in One Month

Better Ways to Lose Weight

If you're ready to ditch the crash diet mentality and work on changing your health long-term, then consider making gradual changes to your daily nutrition and increase your physical activity. The Centers for Disease Control and Prevention (CDC) says that people who lose weight gradually at a pace of about one to two pounds per week are more successful at keeping it off.

To reach and maintain your goal weight, the CDC also stresses the importance of physical activity. The Physical Activity Guidelines for Americans recommends at least 150 to 300 minutes a week of moderate-intensity or 75 to 150 minutes a week of vigorous-intensity aerobic exercise. Plus, two to three days of strength training focusing on all the major muscle groups.

But if you want to lose weight, Harvard Health Publishing says you may need to go beyond the 300 minutes of moderate-intensity exercise a week and reduce the number of calories you eat. Only meeting the minimum standard of 30 minutes of daily exercise for improved health is not enough to help you lose weight. For a loss of one pound per week, consider reducing your daily calories by 250 and increasing your physical activity to burn at least 250 calories.