The HCG diet is a very aggressive and restricted weight loss protocol. The HCG diet restricts dieters to only 500 calories a day and is considered a "very low calorie diet." According the UCLA Center for Human Nutrition, a very low calorie diet is a meal plan that is 800 calories a day or less. Proponents of the HCG diet claim that you can safely lose 1 to 3 lbs. a day without experiencing extreme hunger or significant muscle loss.
The HCG diet includes only two solid food meals that are approximately 250 calories each. You will eat an identical meal for both lunch and dinner. You will not eat breakfast or have any snacks in between. To put this in perspective, for most people, following the HCG diet protocol is the equivalent to eating just one regular meal a day or 1/4 the amount of calories that you currently eat. In addition to extremely restricted meal plan, dieters receive a single daily shot of 125 ius of HCG, human chorionic gonadotropin, that is supposed to suppress your appetite according to the "Los Angeles Times."
Muscle loss is very common side effect of the HCG diet. The majority of weight that you lose while following the HCG diet will be muscle and water because the diet is so low in calories and deficient in protein. While dieting, dietary protein helps you maintain your lean muscle tissue and prevents your body from catabolizing muscle tissue for energy. Diana McGuire, teaching professor of Nutrition, Dietetics and Food Science at Brigham Young University, explains that all 500 calories from the HCG diet will be used as energy and not to support and retain muscle tissue. After your body uses the 500 calories for energy, its next source of energy will be your muscle tissue, which it will consume very quickly.
HCG Does Not Support Weight Loss
According to Jennifer K. Nelson, Registered and Licensed Dietitian for the Mayo Clinic, any weight that you lose by following the HCG diet is because of the extreme caloric restrictions, not because of the HCG. The U.S. Food and Drug Administration approves HCG as fertility and hormone replacement therapy medication, not as a treatment for obesity or as a weight loss aid. This is because after over 50 years of research, not one legitimate peer-reviewed clinical study exists even suggesting that HCG supports weight loss, reduces appetite, spares lean muscle or does anything that proponents of this diet claim. Following the HCG diet is really no different than just starving yourself by eating 500 calories a day.
Preventing Muscle Loss
If you are dieting to lose weight, ideally, you will want to lose fat tissue and not muscle tissue. This results in the lean or "toned" look that many people are trying to achieve. The University of Illinois gives guidelines for healthful weight loss that will not result in muscle loss or other unwanted side effects. Reduce your daily caloric intake by 500 to 1000 calories. For most people, this will produce fat loss of 1 to 2 lbs. a week while keeping muscle loss to a minimum. Any weight loss beyond 2 lbs. a week is often muscle loss. The University of Illinois note that most people require 2,000 calories a day, four times more than the HCG diet. In an effort to preserve muscle, you will not want to reduce your caloric intake too far beyond 2,000 calories.