Feb. 8, 2007 -- Imagine that you could put your diet on overdrive and speed up the fat-burning by 50 percent by simply popping a pill.
Well, it's a reality, and now you won't even need a prescription.
There are plenty of weight loss products out there, but the Food and Drug Administration says Alli is the first diet pill that really works. The FDA approved it this week for nonprescription use.
The pill is taken with meals and blocks the absorption of fat, but it's hardly a magic potion. Users must also exercise and eat a low-calorie, low-fat diet.
"I think this is something that people who are committed to the idea of losing weight carefully can use and can use effectively," said Dr. Arthur Frank, the director of George Washington University Weight Management Program.
GlaxoSmithKline, which markets Alli, says those taking the drug can lose 50 percent more weight than those dieting alone.
But one FDA critic calls the medication dangerous, saying it can cause precancerous lesions.
"It's too bad that the FDA has sided with Glaxo and approved this drug. We strongly recommend people do not use this drug," said Dr. Sidney Wolfe of the group Public Citizen.
Glaxo insists that the drug is safe and expects that 5 million to 6 million Americans will use it.
Alli can cause diarrhea, but less so if a dieter eats less fatty foods; in that way, it encourages users to eat right. The pills will be on store shelves just in time for the summer bathing suit season.
"It [Alli] can work," said "Good Morning America" medical editor Dr. Tim Johnson. "It's been on the market since 1999 as Xenical."
Although the side effects such as diarrhea can be annoying, they're not fatal, according to Johnson.
"It's not lethal, but it can be grave socially speaking," he said. "[It's] not something you want while on a date. … That's one reason the drug hasn't really taken off."
Johnson said that although you could lose weight on the drug without diet and exercise, patients would lose more adding those elements.
"I call it a minor aid," he said. "It's now over the counter, and I personally think that's a good thing."