Do Any Diet Pills Actually Work? Experts Weigh In

by Jessica Smith, REDBOOK

You see ads for them constantly-all touting the alluring promise of rapid weight loss in a pill. But do over the counter (OTC) diet pills really work? And is it safe to take them? We asked experts to weigh in on the reality of those pill promises.

Do they work?

"Diet pills do offer support for many people trying to lose weight. However, most of my clients who report benefits (from taking diet pills) have them only short-term, and the regain more weight than they have lost with in a few weeks following cessation of the medication," says Lisa Cohn, a registered dietitian, and president of Park Avenue Nutrition in New York City. "And while some pills may help suppress appetite, they don't do anything to promote long-term weight loss. Without nutrition education, dietary changes, and skills for self-management-the pill approach is sure to fail once it is stopped. The business of losing weight includes selling pills, not addressing the basis of the eating problem and creating a dependent group of people (failure breeds more business)."

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"I have had many patients come in requesting diet pills or are on them at the time of their initial visit, but usually after we carefully investigate their diet, lifestyle, emotional relationship to food and supplements we are able to agree that the diet pill is not going to be the answer in successful weight loss," says Dr. Jaime Schehr, a naturopathic doctor and registered dietitian in New York City. "I have not seen any success with diet pills sustained weight loss. Diet pills usually contain laxatives, diuretics and or caffeine that can cause a person to lose significant amounts of water, which presents as weight loss. I believe that if there were a pill available that effectively produced weight loss, more people would be taking it and our obesity rates would likely decline. For now, I recommend the old fashioned way of diet and exercise."

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Are they safe?

According to the Mayo Clinic, OTC diet pills aren't held to the same standards as prescription medications, so they can be sold with more limited evidence of effectiveness and safety-meaning consumers need to be even more wary of OTC products.

"OTC diet pills are the most readily available, and the most abused, says Cohn. "And they have a wide range of side effects-including altered heart rate, create digestive distress, dehydration, disrupt sleep patterns and interference with vitamin absorption."

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"Some of the most dangerous ingredients found in diet pills include Ephedra (ma huang), S. cordifolia (country mallow), phenolphthalein (a laxative suspected to be cancer causing). Recently some diet pills have been manufactured with ingredients that are supposed to only available as prescriptive medications, which need to be closely monitored by a physician including sibutarmine (an appetite suppressant), HcG (a pregnancy hormone), phenytoin (an antiseizure medication) and bumetanide (a diuretic). Diet pills with the above ingredients should be avoided. Other common ingredients in diet pills include xenical, chitosan, conjugated linoleic acid (CLA), green tea extract, laxatives and caffeine. These ingredients may be less dangerous than the previously noted but should be used with caution and under the supervision of a physician," says Dr. Schehr.

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The bottom line? Most OTC pills have limited benefits, at best, and won't help over the long term. And worse, many of their side effects outweigh any of their limited benefits. Why take chances with your health? Stick with dietary and exercise changes for a healthy, slim body-sans side effects.

Jessica Smith is a certified fitness lifestyle expert and creator of the 10 Pounds Down DVD series.

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Reprinted with permission of Hearst Communications, Inc.

photo credit: Peter Dazeley