5 Extreme Diets You Shouldn't Try

Beware these dangerous diets.

Losing weight is hard work, so it's no surprise that people often look for a quick fix. But these diets, which often focus on one "magic" ingredient that promises to help you get the body you want quickly, are the equivalent of get-rich-quick schemes, and don't offer any real, long-term weight-loss solution.

But first, what is a fad diet?

These diets are referred to as "fad diets" because they come in and out of popularity, and are also referred to as "crash diets" because they are undertaken with the goal of losing a large amount of weight in a small amount of time. However, they are often dangerous -- restricting your calories to levels far below what your body needs, potentially leading to malnutrition and other health effects. "They may eliminate entire food groups, or they may lack variety, which in turn omits some vital nutrients that your body needs to function optimally," says Nina Eng, chief clinical dietitian at Plainview Hospital in New York. "Fad diets often do not include exercise, and they do not teach healthy lifestyle behaviors and therefore do not cause sustainable weight loss."

The tapeworm diet

The tapeworm diet was around in the 1950s, and yes, it's exactly what it sounds like. People would swallow tapeworms, which are parasites that stick to your intestines and absorb nutrients, to cause weight loss.

"The tapeworm then eats up excess calories, so people think they can continue to eat like they have and still lose weight," says Keith Ayoob, an associate clinical professor of pediatrics who specializes in weight loss at the Albert Einstein College of Medicine in New York. "But there's no free lunch with tapeworms. Tapeworms are parasites, and you want them out of your gut, not in it. Tapeworms can also cause unpleasant side effects, including abdominal cramps, diarrhea and fatigue, and if they stay in your system, all those calories they're eating make them grow -- sometimes into an intestinal blockage."

Thankfully, tapeworms are now illegal for weight loss in the United States.

The hCG diet

hCG is a hormone released by women during pregnancy and is approved by the Food and Drug Administration as a treatment for infertility. The theory is that hCG, taken as a drop or an injection, revs up metabolism, making it possible to lose up to 30 pounds in a month -- a claim that Eng says is bogus. "Individuals will lose weight on this diet," she says, "but simply because only 500 calories are permitted daily, which does not likely supply enough protein either."

The cotton ball diet

Do cotton balls look appetizing to you? If so, you might have finally found the perfect diet! Simply soak cotton balls in juice or a smoothie, swallow and watch the pounds fall off. (Note: Please don't do this, it's incredibly dangerous.)

"This diet can be called the bleached, polyester fiber, chemical diet too, because that is what most cotton balls are made of, and that is what you will be eating," Eng says. "Besides causing malnutrition, because there are no nutrients in cotton balls, this diet could cause choking or may lead to an intestinal blockage or obstruction."

The cabbage soup diet

At least this diet focuses on real food! On the cabbage soup diet, you essentially eat nothing but, you guessed it, cabbage soup for one week, supplementing it with fruits and vegetables on certain days, with the promise of losing up to 10 pounds in a week. "This is a bad idea," Ayoob says. "It only lasts seven days and maximizes water loss, not fat loss. It's not sustainable and it's low in protein, so you'll lose some muscle mass during the week you're on it, no question about it."

Ear stapling

Ear stapling isn't exactly a diet, but it's still meant to help you lose weight. It involves having surgical staples placed on pressure points in your ear, similar to acupuncture, and is thought to suppress your appetite and help you eat less for the months the staples stay in. There's no specific promise of how much weight you will lose, nor is there any evidence that the procedure is effective, according to Mayo Clinic.

The proper way to lose weight

If you really want to lose weight, you need to develop healthy eating habits that you stick with for the rest of your life -- going on and off diets constantly won't help you sustain your weight loss, Ayoob says. "The term 'diet' implies a temporary way of eating that when discontinued will foster old eating habits causing weight to be regained," he says. "For weight loss to be sustainable you should be able to follow healthy eating practices over a long period of time. A variety of food should be consumed and caloric intake should be sufficient."

Amir Khan is a Health + Wellness reporter at U.S. News. You can follow him on Twitter, connect with him on LinkedIn or email him at akhan@usnews.com.