Alicia Silverstone is the latest celebrity to strip down for PETA, baring it all to promote the organization’s anti-wool campaign.

Holly Madison, Katrina Smirnoff, Eva Mendes, Kym Johnson, Dennis Rodman, Olivia Munn and plenty of other stars posed for promos for People for Ethical Treatment of Animals. But do these attention-grabbing ads make any difference?

PETA is confident that the nude ads spread the word.

“For decades, PETA has been using beautiful, sexy ads to convey a serious message and turn heads in order to open hearts. And it's certainly working. In less than 24 hours, on Facebook alone, Alicia Silverstone's gorgeous "I'd Rather Go Naked Than Wear Wool" ad led more than 350,000 people to watch her video on how sheep are killed, punched, stomped on, and cut up. From Hollywood A-listers to everyday men and women who promote vegan eating by showing off their fit bodies, we find that when people get naked, others pay attention to the plight of animals used for food, fashion, or entertainment.”

But several experts told us the star-studded advertisements are unlikely to have an influence.

“I don't think it makes most people rethink things,” said pop culture expert Cate Meighan. “… It's always cool if you're in a position of notoriety to support various causes for sure, but it's really hard to change someone's mind about social, political or religious issues. Those topics run deep, especially right now and a show of support for PETA isn't likely to make someone stop eating meat or prevent them from wearing fur.”

Longtime Hollywood PR guru Howard Bragman agreed. He told FOX411 the celebrity PETA ads are old news and “just not a big deal anymore.”

However, animal rights activist Jane Velez-Mitchell argued the stars’ nude snaps make headlines.

"Stars get naked for PETA because it's a way to get the word out about animal cruelty in the fur, meat and dairy industries,” she said. “When PETA tells it in straight, in a formal news conference, mainstream media ignores them… Media needs to cover animal rights as the serious issue it is for animals, the climate and human health. Then, stars won't have to get naked."

Plus PR expert Ryan McCormick said the ads can help boost the stars’ personal images.

"When celebrities take off their clothes for the purpose of raising awareness of a cause, they are showing a vulnerability,” he said. “They're also relaying a message that they have nothing to hide. Because of these two elements, I think they minimize their chances of eliciting a negative provocation against their cause… Using sex and beauty to sell products has been a part of our culture for a very long time and this another expression of that practice."