There are notable exceptions. In 2003's "Something's Gotta Give," Diane Keaton said she did nothing special to prepare for her first nude scene at 57. "I thought, 'It's going to be a woman's body and that's the way it is,'" she told About.com.
Keaton had also grown more comfortable with her body and no longer had the same hang-ups about showing it onscreen.
"Your idea about your body changes completely as you get older," she told Entertainment Weekly at the time the movie came out. "Now, I just see it as a body. It's not like this precious commodity that I have to hide because I'm, like, Omigod, I don't want anyone ever to see me ever-ever, which I felt for about a bazillion years."
Many audiences commented on how great Keaton's figure looked. Not so with Bates. When the actress, then in her mid-50s, flashed Jack Nicholson in "About Schmidt" in 2002, "It was a shock," Basinger said. "Bates was fabulous in this movie, but seeing her naked is a shock, because we are never confronted with the site of a real 40-something woman carrying some weight, unless we are looking in the mirror. Even Jack Nicholson's character was repelled by her."
Bates took her clothes off because the part called for it. Tomei said she did the same thing for "Before the Devil Knows You're Dead" in 2007, a year before she played a stripper in "The Wrestler," because she wanted to work with director Sidney Lumet, who insisted on explicit nudity for her character.
"I trusted Sidney," Tomei told the Los Angeles Times. "I trusted his taste, and that was a requirement of the role, and I wanted to work with him enough that I was willing to take that leap of faith."
Sobchak said Tomei's decision to strip in "The Wrestler" was a good career move because it got her noticed again. Blogger Silverstein, on the other hand, said the film overdid the nudity.
In the case of "The Proposal" and "Something's Gotta Give," Silverstein said the nudity served as humor in the film.
"It was something you could see happening," she said. "A lot of times where younger women were shown naked or semi-nude, it's gratuitous. When you get into a conversation with older women, it's not about pleasing the male eye or male desire, it's about the script."
While younger actresses, like Jessica Alba, Natalie Portman and Reese Witherspoon, have made it a point to swear off nude scenes, in part, because they worry about the images being widely circulated on the Internet, older actresses appear more at ease with the idea of showing skin.
But Parker, 44, publicly regretted going nude on screen for her Showtime drama series "Weeds."
"I didn't think I needed to be naked, and I fought with the director about it, and now I'm bitter," she told More magazine in June. "I knew it was going to be on the Internet: 'Mary-Louise shows off her big nipples.' I wish I hadn't done that. I was goaded into it."
The bottom line is the decision to undress rests with the actress. "I don't think you have to take your clothes off to be a star that shines for a very, very long time," Sobchack said. "That's not the criteria one way or the other."