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The Skinny on Diet Scams

Experts weigh in on the top 5 diet scams and how to avoid them.

Top Diet Scams continued...

1. Metabolism-boosting/calorie-burning pills

At the top of the list of diet scams are pills based on herbal ingredients that promise to boost your metabolism and help you burn calories or fat faster.

"New herbs always seem to percolate to the top as potential diet aids, as one leaves another shows up because the FDA doesn't monitor herbs," says Zanecosky. "Most of time they are just ineffective; once in a while they are dangerous."

Two recent examples of herbal diet pills that caught the attention of the FDA as dangerous are ephedra and kava (Piper methysticum, also known as kava kava).

Until recently, ephedra was found in many herbal dietary supplements for weight loss, but in February 2004, the FDA banned the sale of ephedra in any dietary supplement in the U.S. due to the risk of illness or injury. The herb is a close chemical cousin of methamphetamine or speed and can cause high blood pressure, irregular heartbeat, insomnia, nervousness, tremors, seizures, heart attacks, strokes, and even death.

Kava is a plant found in the islands of the South Pacific. Supplements containing the herbal ingredient are often promoted for relaxation as well as weight loss. But the FDA issued a warning in 2002 that use of supplements containing kava has been linked to severe liver injury.

2. Fat- and carb-blocking pills

Pills that claim to block your body's absorption of fat and more recently carbohydrates are also commonly-sold diet scams.

Even if these fat and carb blockers worked as they say they do, researchers say the effects can be dangerous if not just plain unpleasant.

It's like making someone lactose intolerant, says Zanecosky. By making the body unable to breakdown nutrients in the body, which leads to gastrointestinal problems like diarrhea, bloating, and gas, these pills also block the absorption of the vitamins that travel with these nutrients.

"Why would someone purposely submit themselves to that?" says Zanecosky. "Some fat blockers might have something in them that can interfere with how people absorb fat, but they've never been shown to help with substantial weight loss."

3. Weight loss teas

Teas based on herbal ingredients are also touted as diet aids, but researchers say the main ingredient in many of these teas is caffeine, which is a diuretic and leads to water loss.

"Losing water isn't losing weight," says Zanecosky. "Caffeine can also increase metabolic rate by a small amount but not enough that you would be able to say that it contributed to weight loss."

Registered dietitian Nelda Mercer agrees and says the only potential weight loss benefit of drinking herbal teas might be using them as a substitute for high-calorie beverages.

Mercer says that with some diet teas, it's the program the comes along with the teas that may sometimes promote weight loss, such as teas that recommend you drink it after dinner and then not eat anything else until morning. That way it could curb late-night eating, but it's not necessarily a result of drinking the tea itself.

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