WASHINGTON - Now that you've indulged in all those holiday goodies and made that New Year's resolution to shed some pounds, the government says don't count on a diet pill to help.

In this March 19, 2003, file photo, a bottle of Xenadrine RFA formula with ephedrine lies in front of a new formula of the medicine, the EFX version, without the ephedrine in South Brunswick, N.J. The Federal Trade Commission on Thursday fined the marketers of four weight loss pills, including Xenadrine EFX, millions of dollars for making false advertising claims. [AP]

The Federal Trade Commission said Thursday it was fining the marketers of four weight-loss drugs a collective $25 million for false advertising claims. Despite that, the pills ¡ª Xenadrine EFX, CortiSlim, One-A-Day WeightSmart and TrimSpa ¡ª will remain on store shelves.

"It is resolution time again, isn't it?" said FTC Chairman Deborah Platt Majoras. "We're implementing our resolution to fight back against companies that use deceptive advertising claims."

Some of the products marketed their claims through infomercials or celebrity endorsements. Anna Nicole Smith, for example, has endorsed TrimSpa.

"Testimonials from individuals are not a substitute for science," Majoras said. "And that's what Americans need to understand."

The FTC investigated a variety of claims, including rapid weight loss and reduction in the risk of osteoporosis, Alzheimer's and even cancer, Majoras noted.

The largest fine was levied against the marketer of Xenadrine EFX, made by New Jersey-based Nutraquest, Inc., formerly known as Cytodyne Technologies. The marketers will pay at least $8 million and as much as $12.8 million. The marketer was identified as RTC Research & Development, LLC, based in Manasquan, N.J.

Majoras said Xenadrine had a study showing that people who took a placebo lost more weight than those taking the pill. The FTC's investigation also found that consumer endorsers ¡ª people who appear in the before-and-after pictures in many ads ¡ª lost weight by engaging in rigorous diet and exercise programs.

A $12 million fine was assessed against Window Rock Health Laboratories, based in Brea, Calif., the marketers of CortiSlim. Majoras said CortiSlim falsely promised that all users would see permanent and fast weight loss, and that its TV infomercials were "deceptively formatted" to appear as talk shows rather than ads.

The Bayer Corp., based in Morristown, N.J., will pay a $3.2 million civil penalty to settle the claims. The FTC said Bayer marketed One-A-Day WeightSmart with unsubstantiated claims including that it increases metabolism. Bayer violated an earlier FTC order requiring all health claims for its One-A-Day brand vitamins be supported by competent and reliable scientific evidence.

The marketers of TrimSpa, Goen Technologies Corp., will pay $1.5 million. Both Goen and TrimSpa are based in Whippany, N.J. The FTC said Goen had inadequate scientific evidence to support claims that TrimSpa causes rapid and substantial weight loss.

Marketers for Xenadrine EFX and CortiSlim did not return telephone calls for comment.

Bayer disagreed with the FTC's description of the company as a marketer of a weight-loss pill.

"It's a multivitamin," said Tricia McKernan, spokeswoman for Bayer HealthCare's Consumer Care Division. "We don't market ourselves as a weight-loss product."

Rather than go through the expense of litigation, Bayer decided the way to "close this issue" was to settle, McKernan said.

TrimSpa released a statement saying the FTC's investigation of a handful of its ads was "amicably resolved" without the company's admission of any liability.

Some of the fines could be returned to consumers who purchased Xenadrine EFX and CortiSlim. The marketers of the other two drugs paid civil penalties.

Consumers who purchased Xenadrine EFX and CortiSlim directly from the marketers will be contacted by the FTC about getting their money back. People who bought the pills over the counter will have to wait a few months for the agency to put up a public notice on its Web site telling them how to recoup money.

Dr. Louis Aronne, director of the Comprehensive Weight Control Program at New York-Presbyterian Hospital/Weill Cornell Medical Center, said people turn to the pills because they promise results with no effort.

"They make it sound like you don't have to do anything but take the pill," Aronne said. He said Congress should regulate diet pills as medication, which would place much more stringent measures on manufacturers and marketers.

Joan Salge Blake, a professor of nutrition at Boston University, said dieters should do what they've heard before ¡ª cut calories, eat healthier foods and exercise.

"If a pill sounds too good to be true, it probably is," she said.