Gen X women, young for their age
"You guys [Gen X] feel that that this look is not antithetical to being good in your profession ... we [baby boomers] assumed that to be feminine and be attractive was at odds with that," Diller says.

Seymour has also noticed this generational change. "I don't think that there are very many women out there who now believe that they have to be ugly to be smart. Or that if you use anti-aging products, hair color or care about what you look like, it means that you don't have brains … that was really the old message: That you couldn't be attractive and smart — that you had to give up one for the other."

Diller and Seymour talk about the pressure Generations X and Y feel to live up to airbrushed, celebrity-driven impossible beauty standards — even if that means a full face of makeup at the gym. "At the gym, we wore sweat pants," Diller says. "Going to bed we wore funny-looking pajamas. You guys have Victoria's Secret now, and waxing. The baby boomer generation had places where we could just let it go. Now there's so much pressure."

Perceptions of middle age

The new attitude translates to the group's beauty habits. Gen-Xers rely on preventive anti-aging beauty regimens to a greater extent than boomers do, according to the Mack's JWT study. A report from the Symphony IRI National Consumer Panel says that Gen X spent $5.3 billion on beauty products in the 12-month period that ended June 26, which represented 28% of all beauty spending.

As they enter their 40s, Generation X women tend to look younger than their mothers and grandmothers did at this age. Less cigarette smoking, more sunscreen use and a greater awareness about nutrition and beauty industry advances help. The media are taking note of the younger looks and greater purchasing power of the generation as women 35 and older frequently grace magazine covers once reserved for teen or twentysomething models. Jennifer Lopez, born in 1969, was named People magazine's 2011 Most Beautiful Person of the Year just a few months before her 42nd birthday. Covers of Allure magazine, just to name one, recently have featured Generation X and older women including Lopez, Catherine Zeta-Jones, Julianne Moore, Eva Mendez, Victoria Beckham, Jennifer Aniston and Eva Longoria.

"You know what's funny about this," says Allure's editor in chief Linda Wells (who is a boomer). "I'm not even conscious of the fact that they're over 35 or over 40 because to me they're just really interesting women who are great-looking, who have great careers, who have something to say and that's why they're on the cover because they have all of those magic combination of qualities."

In an Allure survey last November, 93% of female and 84% of male respondents said there is greater pressure to look younger today than there's ever been before. But on the positive side, "middle-age" women were seen as more attractive today than they were in a survey Allure took 20 years ago. And younger men are most likely to see the demographic as "hot."

Like baby boomers, Wells says, Gen-Xers have grown up not accepting the status quo. That can translate to wearing long hair even past a certain age, eschewing "mom jeans" and participating in music, sports and other interests once reserved for "younger women."

Molly Ringwald, 43, is a prime example. Ringwald has been heralded as a generational touchstone, starring in the John Hughes classics "Sixteen Candles," "The Breakfast Club" and "Pretty in Pink." Most recently she's known as the mother of a teen in the television show "The Secret Life of the American Teenager." She also wrote the book "Getting the Pretty Back: Friendship, Family and Finding the Perfect Lipstick."

Ringwald, who had her children later in life, says that turning 40 is a milestone that people deal with in different ways. "Looking back at pictures of my mother and grandmother, 40 just seemed so old," she notes. "Some people get depressed. Some people get inspired. I would say it was a combination for me. Leading up to it, I was sort of a little nervous because it seems like such a big deal." But 40 ended up being a positive turning point that kicked her life into high gear. Today she is a mom who acts, sings jazz and writes.

To stay beautiful she believes in trainer workouts and terrific skin care and one secret ingredient.

"It sounds really corny, but I really do think that the most important thing that you can do is make happiness a priority," she says. "Because I think that is the main thing that seems to keep me looking good, giving me the shine and giving me the glow that no other beauty product, no surgery, nothing can … if you're not happy, figure out how to get happy. It will change your entire life, and it will make you look 10 years younger."