Is the hCG Diet Effective—and Safe?

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Human chorionic gonadotropin (hCG) is a hormone that's normally produced by women during pregnancy. Because it is purported to have fat-burning qualities, it is also the foundation of the so-called "hCG diet," which proponents claim can result in dramatic weight loss. The diet is very controversial, however, for a variety of reasons. And according to some, it is a complete hoax.

What Is hCG?

hCG is produced by the placenta early in pregnancy and excreted in the urine, making it responsible for a positive result on a home pregnancy test. Its main function is to make the uterus hospitable for a growing fetus. hCG can also increase metabolism and mobilize the burning of fat to ensure that energy is provided to the developing fetus, as well as to protect the pregnancy even if the mother is facing a situation of starvation or is only able to get limited calories. hCG is also used at high doses to treat infertility.

hCG's Role in Your Pregnancy

The Theory Behind hCG for Weight Loss

For weight loss, hCG is used in minute concentrations, along with a very low-calorie diet, as a way to stimulate the hypothalamus and trigger fat-burning.

The combination of hCG with a very low-calorie diet is sometimes referred to as the hCG Protocol, the hCG Diet, or the Simeons diet, after British physician Dr. A.T.W. Simeons, the doctor who first proposed it as a weight loss method in 1954.

The theory is that the hCG triggers the burn-off of stored fat and allows for weight loss without the normal side effects of a low-calorie diet, such as hunger, irritability, headaches, weakness, reduced muscle mass, or reduced metabolism.

According to proponents:

  • hCG causes the hypothalamus to trigger fat to move out of storage and become available for use as immediate energy. The combination of the released stored energy, plus the energy from the low-calorie diet, adds up to several thousand calories a day of energy available for daily function. Since many of the calories are coming from stored fat, the theory goes, the fat disappears.
  • hCG prevents the metabolism from dropping, despite the very low-calorie intake. The normal response to a very low-calorie diet is for the metabolism to slow down, which can cause fatigue and stall weight loss. The theory is that the hCG circumvents this mechanism with the hypothalamus and keeps metabolism at a stable level.
  • Because hCG targets fat loss, muscle mass is theoretically less likely to be lost.
  • After weight loss on hCG, hypothalamic balance is restored. Leptin and insulin resistance may also be reduced, making it easier to continue losing weight or to maintain weight loss.
  • For patients who have been yo-yo dieters or on very low-calorie diets, hypothalamic dysfunction that has slowed metabolism or reduced their caloric needs may be reversed, allowing the metabolism to return to normal.
    Quick Weight Loss Plans: What to Consider

    Phases of the hCG Protocol

    Generally, the hCG protocol is straightforward. The concept is that you follow a 20- or 40-day cycle of using hCG, along with a very low-calorie diet composed of very specific foods. This allows you to lose a substantial amount of fat, primarily from areas of the body that have excess fat deposits.

    While simple, proponents caution that hCG protocol needs to be followed very carefully.

    You can't take hCG and eat anything you want, or go above the calorie limits. The diet is specifically designed to work with the hCG.

    The protocol involves three phases, including:

    1. The loading phase: You start taking hCG and eat plenty of high-fat, high-calorie foods for two days.
    2. The weight loss phase: You continue taking hCG and eat only 500 calories per day for three to six weeks.
    3. The maintenance phase: You stop taking hCG and gradually increase food intake, but avoid sugar and starch for three weeks.

    Those seeking to lose small amounts of weight may spend three weeks in the middle phase, while those seeking significant weight loss may follow the diet for six weeks and even repeat all phases of the cycle several times.

    hCG meal plans generally advise that each meal contain one portion of lean protein, a vegetable, a piece of bread, and a fruit. Butter, oils, and sugar should be avoided, and you must drink a lot of water.

    Is the hCG Protocol Effective?

    The use of hCG as part of a specific weight loss protocol is a controversial approach and many physicians refuse to prescribe it. 

    The main criticism of the hCG protocol is, frankly, that it's ineffective, and that unscrupulous online marketers have latched onto it as a money-making source.

    Critics of the hCG protocol point to research studies that have found that hCG is no more effective than placebo, and say that the effects of the diet are due to being on a very low-calorie diet of 500 calories a day—not the hCG.

    Some critics suggest that the hCG diet is simply a ketogenic diet, and what's happening is that the limited carbohydrates in the diet are sending the body into a state called ketosis, where appetite typically is suppressed. Stored fat is burned during ketosis, but over time, there are concerns it can increase the risk of kidney stones and gallstones.

    It's also important to note that while hCG is prescribed for and has approval from the U.S. Food and Drug Administration (FDA) as a fertility treatment, its use as a weight-loss treatment is considered "off-label."

    The FDA's Stance

    The FDA requires physicians to advise patients that hCG has not been demonstrated to be an effective treatment for weight loss.

    HCG has not been demonstrated to be effective adjunctive therapy in the treatment of obesity. There is no substantial evidence that it increases weight loss beyond that resulting from caloric restriction, that it causes a more attractive or “normal” distribution of fat, or that it decreases the hunger and discomfort associated with calorie-restricted diets.

    Is hCG Safe?

    High-dose hCG for fertility treatments can result in ovarian hyperstimulation and rupture of ovarian cysts, among other problems. The doses used for fertility treatment, typically 5,000 to 10,000 IU are, however, much higher than the 125 IU a day typically used in the hCG protocol.

    Furthermore, health food stores and online retailers sell homeopathic products that claim to contain hCG, but in fact do not. These products are not regulated and there is no proof they are safe. In fact, the FDA has deemed it illegal to sell these products.

    Real HCG is administered as a fertility drug in the form of injections and is available only through a doctor's prescription. Homeopathic products sold online do not contain HCG and therefore cannot raise blood levels of the hormone.

    The FDA has received reports of serious adverse events associated with the use of hCG injections for weight loss including pulmonary embolism, depression, cerebrovascular issues, cardiac arrest, and death. 

    Still, there are practitioners who are comfortable prescribing hCG injections for weight loss. They have different safety guidelines that they themselves follow, but in general, hCG use is not advised in:

    • Women who are pregnant or nursing
    • Insulin-dependent diabetics
    • Anyone with heart disease
    • Anyone with cancer or a history of cancer

    Some physicians also rule out anyone with gallstones, a history of gout, epilepsy, or kidney disease.

    A Word From Verywell

    Given the fact that there is no research to back up the effectiveness or safety of the hCG diet, the FDA's position that the diet is unsafe, and that homeopathic hCG products are illegal, you are better off choosing a different approach for weight loss. Talk to your physician or a nutritionist for programs that are suitable for you.

    If you are still considering the hCG diet, be sure that you are working with a reputable physician and that you provide him or her with accurate information about your medical history.

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