Nutritionist and biochemist Dr. Ingrid V. Van Heerden, a contributor to the Health24 website, explains that this diet is unsafe and unhealthy because of the low-calorie intake and because it is an unbalanced diet. Dr. Van Heerden states that people who are drastically reducing their calorie intake per day will feel weak, hungry, tired and can be receptive to illness. Dr. Van Heerden adds that because this diet cuts out certain food groups, people may suffer from vitamin and mineral deficiencies. Not to mention that because this diet is lacking fruits, dairy, and whole grains, people may also experience kidney problems.
According to the Weight-Control Information Network, an information service of the National Institute of Diabetes and Digestive and Kidney Diseases, a low-calorie diet such as the 13-day diet should only be administered by your physician. In comparison, your physician would use commercially prepared formulas which would include the necessary micronutrients to ensure that there is no lack of nutritional requirements.
I had the pleasure of speaking to Dr. Susan S. Percival, a professor at the University of Florida who specializes in Food Science and Human Nutrition. The first thing she said when I mentioned the 13-day diet was: “That’s three pounds a day. I think the diet has broken the laws of physics.” Dr. Percival is correct when she mentions the amount of weight a person has to lose per day in order for this diet to be successful.
But rather than using the 13-day diet plan, why not choose a healthier, realistic plan? Dr. Van Heerden suggests aiming for weight loss of 1 to 2 pounds per week which will include 45 to 60 minutes of physical activity per day along with a balanced diet if fruits and vegetables and reduced consumption of sweetened drinks.
