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A new diet craze, the hCG diet, is unsafe and unsustainable for long-term weight loss, health experts warn.
People who go on the fad diet eat about 500 calories a day and take supplements (either via drops or injection) of human chorionic gonadotropin (hCG) several times a week. The hormone is produced by women during pregnancy.
But eating so few calories a day is dangerous and puts the body in a starvation-type state, said Katherine Zeratsky, a registered dietitian at the Mayo Clinic.
When the body is starved for calories, the body's metabolism slows down to preserve energy and "in the long run, that'll sabotage your weight control efforts," Zeratsky told MyHealthNewsDaily.
"The question is how long can someone sustain a restrictive diet of 500 calories, and the realistic answer is not long," she said. When a person gets off the diet, he or she will likely overeat and overindulge because the body has been in such a restrictive mode, Zeratsky said.
500 calories a day
The only reason why anyone loses weight off this diet is because they're eating 500 calories a day, Zeratsky said. While calorie intakes are different from person to person, most nutrition information at the grocery store is based off a 2,000-calorie diet. For healthy weight loss , a daily intake of 1,200 to 1,800 calories is generally acceptable, she said.
Eating 500 calories a day is equivalent to eating one cup of chopped-up chicken breast, with two servings of fruit and two servings of vegetables -- in essence, it's about the amount of calories a person would consume in just one meal.
"I think there're more reasonable, sustainable and healthier ways to control your weight," she said.
When a body is subsiding off 500 calories a day, the body leeches protein from the muscle in the heart, and that makes the heart muscle irritable, which can lead to ventricular tachycardia and sudden cardiac death, said Dr. David L. Katz, director of the Yale-Griffin Prevention Research Center in Connecticut.
"So I think the diet is not just folly, I think it's potentially fatal folly," Katz told MyHealthNewsDaily.
The 'Dumbo feather'
So what's the purpose of the hormone?
It's the so-called "Dumbo feather" that makes you think you can fly, Katz said.
"If you told people you can lose a lot of weight by eating 500 calories a day, no one would reach for their credit card," he said. "The hormone is the excuse -- the promise of magic."
As far as the actual injections of hCG go, risks are -- as far as experts know -- relatively small. Bleeding, infection and blood clots are all possible, but risks of those are small, Katz said.
But what's also dangerous is the fact that experts could be unaware of some of the potential dangers of the hormone, he said. Right now, hCG is only approved as one part of a fertility treatment for women, so that the body can mimic the state of pregnancy. Only small studies have been done so far on the efficacy of using hCG for weight loss, where evidence of harm is hard to detect because of the small sample sizes, Katz said.
When a woman takes hCG, her blood tests will indicate that she is pregnant because the hormone is only produced during pregnancy. If that woman were to go to the hospital for abdominal or pelvic pain but failed to tell her doctors about taking the hCG, the doctors might think she is having an ectopic pregnancy simply because her hCG level would be positive, said Dr. Pieter Cohen, assistant professor of medicine at Harvard Medical School and an internist at Cambridge Health Alliance in Massachusetts.
"They'd do an ultrasound, see no pregnancy and assume it's ectopic, and that's a surgical emergency," Cohen told MyHealthNewsDaily. "These are the sorts of things that can happen when people are pursuing this paramedical approach to dieting."
And for men, the only time hCG is naturally high in their bodies is when they have cancer, Cohen said.
"So why are people injecting something that is only at a significant level in men when they have cancer?" he said. "That's absurd."
Origins of an idea
So where did the idea that hCG can help with weight loss come from?
In the 1960s, a doctor working at a Roman clinic was treating men with a rare endocrine disorder, in which their bodies were missing hormonal signals to trigger production of normal male hormones, Cohen said.
As part of the treatment for this rare hormonal deficit in men -- which often resulted in the patients becoming overweight -- this doctor injected them with hCG. When treated, they lost weight, he said.
"But that was for someone who was sick, and being treated back to normal levels of hormones," Cohen said. "That's the only reason why they lost the weight."
That doctor then questioned whether hCG was a viable option for weight loss for other people without the rare endocrine disorder. He performed experiments where he put people on 500-calorie diets and gave them hCG supplements, and found that they lost weight. But skeptics weren't sure if it was the diet or the hormone that prompted the weight loss, Cohen said.
Subsequent studies revealed that it wasn't the hCG that prompted the weight loss -- it was the low calorie intake. A 1995 review of studies, published in the British Journal of Clinical Pharmacology, showed that taking hCG did not help people lose weight, did not treat obesity and did not reduce feelings of hunger or promote feelings of well-being.
"A thyroid disease is the same way," Cohen said. "If you have low thyroid function, you can gain weight from that. You give someone back the thyroid hormones, they lose weight. Treating a disease can cause weight loss by balancing hormones in the body."
But for most people who don't have hormonal imbalances in the body, taking hCG does absolutely no good, he said.
Pass it on: The hCG diet is dangerous because it promotes an extremely low intake of calories, and it is not good for sustained weight loss, experts say.
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