Weight-loss products containing the hormone HCG are illegal and potentially dangerous, the Food and Drug Administration (FDA) said today, and consumers are advised to steer clear of the oral drops, pellets and sprays that can be found online and in retail stores.

The FDA, along with the Federal Trade Commission, issued warning letters today to seven companies selling over-the-counter, homeopathic weight-loss products marketed as containing HCG.

The products are marketed with claims that hormone human chorionic gonadotropin, which is found in the urine of pregnant women, is a "natural" way to increase metabolism and spur weight loss.

But the products are labeled with the recommendation to consume no more than 500 calories a day, and there is no evidence that HCG contributes to weight loss beyond what comes with such severe a calorie restriction, said Elizabeth Miller of the FDA's Center for Drug Evaluation and Research, speaking at a news conference today.

There are no FDA-approved weight-loss products that contain HCG, and HCG products that are marketed for weight loss are unproven and potentially unsafe, Miller said.

Moreover, limiting calorie intake to 500 calories a day is unhealthy, and increases risk of developing gallstones, heart arrhythmias and electrolyte imbalances, Miller said.

"The weight-loss industry, perhaps more than any other, is fad-driven," said Richard Cleland, an assistant director at the Federal Trade Commission. "It's also fraud-driven," Cleland said, citing the past examples of products containing the plant Hoodia gordonii and acai berries, which were also marketed as weight loss products without evidence of being effective or safe.

Neither agency had data available on how many consumers have bought such products, but the heavy marketing on the Internet indicates there are many purchasers, Cleland said. A recent survey showed  that almost 5 million Americans each year are victims of weight-loss fraud, he said.

The warning letters inform the companies that they are violating federal law because they are advertising products without having reliable scientific evidence that their claims are true. Letters were issued to Nutri Fusion Systems, Inc, Natural Medical Supply, LLC DBA HCG Complete Diet, HCG Platinum, LLC, Theoriginalhcgdrogs.com, HCG Diet Direct, LLC, Hcg-miracleweightloss.com and HCG Drops, LLC.

Other companies marketing similar products should also take action to correct any violations, Cleland said.

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