Weight Loss: Best Diet Pills  

We know ephedra helps people lose weight. We also know it isn't for everybody, which is why the warning labels told people with high blood pressure, heart disease, and other health problems to stay away. But when Baltimore Orioles pitching prospect Steve Bechler died after using ephedra -- even though he ignored warnings that were so specific to his health problems that his picture might as well have appeared on the label -- supplement companies knew it was all over. The FDA banned ephedra more than two years ago.

But the manufacturers are still selling their products. They've simply reformulated them, promising the same results but with different, "ephedra-free" ingredients. They're telling us we can have our cake and eat it, too, confident that none of those frosting-covered calories will end up hanging over our belts. And even before the FDA ban, we were buying it -- in 2002, sales of just one ephedra-free weight-loss supplement totaled $25 million. But what are we really getting for all that green? Science or snake oil? A little of both, it turns out. Here's a sampling of what's inside today's kinder, gentler fat burners.

The product: Ephedra-free Hydroxycut

The claim: "Can help increase your body's weight loss potential . . . and reduce hunger cravings!"

Primary active ingredient: Hydroxycitric acid (amount unknown)

An extract of an Indian fruit called malabar tamarind, hydroxycitric acid (HCA) is touted as a natural appetite suppressant. And that's partly true -- it is natural. A study published in the Journal of the American Medical Association determined that a 1,500-milligram (mg) daily dose had absolutely no effect on appetite or weight loss. Still, the company cites a study (as yet unpublished) that found that people who took 2,800 mg HCA every day for 8 weeks lost twice as much weight as those taking a placebo. But experts remain unconvinced. "Having worked with the product, I am skeptical," says James Hill, Ph.D., director of the University of Colorado's center for human nutrition. "It's possible that higher doses have this great effect, but I personally think it's unlikely."

The verdict: Until there's evidence otherwise, drop this acid from your supplement shopping list. Instead, stick with a fruit extract that's a proven hunger squelcher: pectin. Just 5 mg of this gelatinlike substance -- the amount in one large apple -- has been found to increase satiety and reduce weight, according to research published in the Journal of the American College of Nutrition.

The product: Xenadrine EFX

The claim: "Uses advanced thermogenic technology!"

Primary active ingredient: Thermodyne complex, including green-tea extract and caffeine (amounts unknown)

The Chinese have been sipping green tea for thousands of years, so this isn't exactly "advanced" technology. But that aside, a study published in the American Journal of Clinical Nutrition did find that when 10 men were given 270 mg EGCG -- a chemical found in green tea -- and 50 mg caffeine, their metabolisms increased by 4 percent, compared with less than 1 percent when they had the caffeine alone. Over the course of a year, this boost to your fat burner could translate to an additional weight loss of 12 pounds. The catch? The study only looked at the effects of EGCG and caffeine over the course of a single day. "Green-tea extract elevates metabolism over a 24-hour period, but we don't know if this effect continues if you take it every day," says Jose Antonio, Ph.D., C.S.C.S., a nutrition and exercise researcher in Deerfield Beach, Florida.

The verdict: Without knowing the amount of caffeine and green tea in Xenadrine, there's no way to tell if it'll work, be it for a day or a week. A better bet: Shortly before you go to sleep, eat 1 cup of cottage cheese, one of the best sources of a protein called casein. You want casein in your bedtime snack because it reduces catabolism, a process in which your body breaks down muscle tissue instead of fat, while you sleep, says Christopher R. Mohr, M.S., R.D., a nutritionist at the University of Pittsburgh. Retain more muscle and your metabolism will speed up over time, causing you to wake up leaner than when you hit the pillow.

The product: Trim Spa Completely Ephedra Free

The claim: "Has an ingredient that prolongs the amount of time that food is available for energy, thus keeping it from being stored as fat"

Primary active ingredient: Glucosamine (300 mg)

Yes, the same glucosamine that greases your joints is supposed to shrink your gut. The theory: Glucosamine, a naturally occurring amino acid derivative, weakens insulin action, which in turn may prevent fat storage. When researchers at the Washington University school of medicine tested this theory on fat rats, they found that giving the rodents 10 millimoles (mM) of glucosamine increased their insulin resistance by 50 percent. Problem is, 10 mM is enough glucosamine to flood every cell in a rat's body. Now, if you were to try to swallow a proportionate amount of the stuff -- well, you couldn't. "The doses used in rodent studies are typically much higher than are used in humans," says Michael Schwartz, M.D., head of the section of clinical nutrition, division of metabolism, endocrinology, and nutrition, at the University of Washington.

The verdict: Save the glucosamine for your bum knee. And if you want to make insulin your ally in your struggle to slim down, check out our primer "The Jekyll-and-Hyde Hormone," on the next page. It explains what to eat (and when) to maximize the hormone's appetite-suppressing powers.

The product: Prolab Therma Pro Ephedra Free

The claim: "Stimulates metabolic rate and promotes fat loss"

Primary active ingredients: Synephrine (60 mg) and Coleus forskohlii (375 mg)

Synephrine is ephedra's chemical cousin, but it may be a weak sister when it comes to weight loss. In a 6-week study published in Current Therapeutic Research, researchers found that people who took synephrine (975 mg), caffeine (528 mg), and St. John's wort (900 mg) daily while also dieting and exercising lost about 3 percent of their body fat, versus no change in those who only dieted and exercised. Not bad, but not necessarily a result of the synephrine, particularly given the megadose of caffeine used. "You can't really say whether it's specifically tied to one of the ingredients or it's a synergistic effect," says Jeff Volek, Ph.D., R.D., an exercise and nutrition researcher at the University of Connecticut. As for Coleus forskohlii, you may burn more calories trying to pronounce the name than you will by taking the stuff; there is virtually no scientific research to support consuming this Indian plant as a way to manage one's weight.

The verdict: Even if synephrine was the force behind the fat loss seen in the study, Prolab's product is about 915 mg shy of the amount the researchers tested. But you can still speed up your metabolism -- just eat more fish, especially salmon and tuna. Several studies have shown that the omega-3 fatty acids in fish can help lower the body's blood levels of leptin, a hormone that can keep our metabolisms stuck in first gear.

The product: Zantrex-3

The claim: "The ultimate appetite suppressant"

Primary active ingredients: Yerba mate, guarana, and damiana (amounts unknown)

This herbal threesome from South America supposedly suppresses your appetite by slowing the digestive process. The evidence: A study published in the Journal of Human Nutrition and Diet shows that people who took the combination for 45 days dropped 10 1/2 pounds more than those taking a placebo. Impressive results, until you consider that the researchers neglected one small detail: food, as in the amount and type everyone ate. "You can't measure weight loss without controlling for diet," says Mohr. For all the researchers know, the supplement group was on Atkins and the sugar-pill subjects were carbing it up. But even if you assume that diet wasn't a factor (and you really shouldn't), it's impossible to know whether Zantrex-3 will work, since there's no mention on the bottle of how much yerba mate, guarana, and damiana is in each capsule.

The verdict: Don't bother going below the equator to shorten your own latitudinal lines. Stay put and time the length of your next meal. "It takes 20 minutes for your brain to recognize that you're full," says Marilyn Tanner, M.S., R.D., a spokeswoman for the American Dietetic Association. If you usually finish in less time, you could be overeating. Can't seem to slow yourself down? Tanner suggests breaking your meals into courses, taking a sip of a low-calorie beverage between bites, and never eating with your fingers -- even if it's a finger food. (You can't fit as much on a fork.)

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