HOUSTON - An animal rights group says Alicia Silverstone appears naked in a television ad promoting vegetarianism that was to debut Wednesday in Houston. AP Video

The 30-second ad was to air about two dozen times in Houston on Wednesday, the People for the Ethical Treatment of Animals said.

PETA said Houston was picked for the commercial's launch because it is often high on lists of cities with unhealthy eating habits. Houston was named the sixth fattest city in the nation by Men's Fitness magazine this year.

Silverstone is shown emerging from a swimming pool and talking about the benefits of being a vegetarian. She obscures the view of her body with her arms as she gets out of the pool, PETA said.

"I wasn't always a vegetarian, but I've always loved animals," the 30-year-old actress said in a statement. "Physically, the effect has been amazing."

Silverstone's screen credits include "Clueless" and "Batman & Robin."