The hCG Diet, popularized in the 1950s for its rapid weight loss results, claims to help dieters lose up to 30 pounds in a month. The plan combines a 500-calorie-a-day diet—less than half the daily calories recommended by the National Institutes of Health for healthy weight loss—with daily injections or drops of hCG (human chorionic gonadotropin), a pregnancy hormone said to diminish appetite and burn stored body fat.
“This diet is very extreme, and I would not try it myself, nor recommend it to even my worst enemy,” says registered dietitian Lona Sandon, an American Dietetic Association spokesperson and assistant professor at the University of Texas Southwestern in Dallas. “The rapid weight loss has to do with the calories, not the hCG. Anyone would lose weight on 500 calories a day.”
And while dieters may lose the weight, is it unlikely that the weight is gone for good. “There is no way you can get all the nutrients you need in 500 calories, and rapid weight loss is not synonymous with being healthy,” Sandon says. “Fad diets like this are the fastest route to rapid weight gain when the diet is over.” And it’s not without its risks. Sandon notes that rapid weight loss can result in electrolyte imbalances, low blood sugar, fatigue, irritability, bad breath and mood swings.
To make things even tougher, Sandon says, “when you restrict your calories to this low of a level, the body actually compensates by increasing hunger-triggering hormones,” making it that much harder to keep the weight off.
Sandon likens the injections, which can cost $1,000 per monthly session, to placebos, and she notes that there’s no scientific data to indicate that the hormone plays any role in weight loss. “The hormone is approved to treat fertility issues, not obesity,” she says. “Research does not support the use of hCG for weight loss.” In a 1995 review of 14 studies on the effectiveness of hCG as a weight loss aid, only two deemed it effective. The recent resurgence of the diet has inspired the Federal Drug Administration to declare homeopathic hCG, like the kind sold online, illegal and fraudulent when it is sold for weight loss.
Because hCG is an approved fertility drug, doctors can prescribe it for “off label” use—in other words, to treat another condition, Sandon says. “The types of medical professionals I see administering it are in private practice weight loss clinics. I’m not aware of any MDs within my university who would promote its use for weight loss,” she says.
The bottom line? “No one should attempt this diet without supervision,” Sandon says.