Kirstie Alley and Organic Liaison LLC's weight-loss supplements are at the center of a class action lawsuit, with plaintiffs alleging Alley did not lose 100 pounds using the supplements as she claimed. The lead plaintiff, Marina Abramyan, sued Organic Liaison LLC, Organic Liaison Management and Alley, claiming they use deceptive before-and-after pictures to market the supplements.

The lawsuit seeks damages for false advertising on behalf of consumers who have bought the supplements since July 2008.

According to Courthouse News, the complaint says Alley actually lost the weight exercising, following a low-calorie diet and dancing for the television show "Dancing with the Stars." Courthouse News reported Abramyan bought the products, but did not lose weight or experience any of the advertised benefits.

Marc Ullman, partner, Ullman, Shapiro & Ullman, said it's illegal for a person to claim she lost weight by using a pill alone, if she also dieted and exercised. "That's misrepresentation and could create liability from a consumer suit like this or even from FTC." He noted before and after pictures are regulated just like claims.

FTC requires that each claim made in advertising be truthful, not misleading and backed by sufficient support. The requirement applies to all advertising claims; testimonials and endorsements are no exception. FDA is also on the watch as it has recently issued warning letters against companies, such as Alistrol Health, that use illegal marketing claims in testimonials.

" If the testimonial is that you use only product X, then the endorser must really use only product X," Ullman said, adding, "Consumers, as always, need to be leery of any product that claims to be able to cause weight loss without the need for lifestyle changes or to be able to cause targeted weight loss (belly fat). These types of claims continue to be red flags for potential FTC enforcement action."

Find out more on what product marketers can say in the INSIDER article, "Testify! Keys for the Legal Use of Testimonials and Advertisements" by attorney Justin Prochnow.