That's not surprising, according to New York City psychotherapist Robi Ludwig. "This is really developmentally the time of life that women plug into themselves and respect themselves, listen to their own voice, and develop their own voice, so it makes perfect sense that they would really feel good, because they're doing that," she tells Yahoo Shine.
With age comes wisdom, she says. "Women in their 20s today are still very much young-minded…They almost see themselves as kidlike. As they're into their 30s, they're beginning to make more adult choices that will serve as the foundation [of the future], but there's still a bit of wanting to please parents, wanting to please bosses, be culturally in sync."
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By the late 40s and into the early 50s, "It's almost like a second adulthood in the sense that you've played by other people's rules, and now the name of the game is, 'What works for me? What makes me happy?' And that's what this phase is all about."
It's liberating, Ludwig says.
Also, 53 is "right between the perfect age of having the last child move out and the perfect age for retirement," points out Regina A. Corso, the senior vice president of Harris Interactive. (The poll says most Americans hope to be empty-nesters at 45 and then retire at 61.)
"There's really a sense that, 'This is my time, mine and my spouse's time,'" Corso says. "You're still working, probably at a decent point in your career, don't have kids at home anymore, and you can start doing what you want to do."
Even if kids aren't in the picture, many women in their early 50s have reached a point in their career where they're making good money, have some disposable income, and can start planning vacations for when they retire, Corso says.
"Fifty-three is still young enough that you're healthy, you can travel and see the world and start crossing things off your bucket list," she tells Shine.
And your love life probably keeps getting better then, too, whether you're married or single. You don't have to worry about having more children at that point. And age might be less of a factor in finding a partner. "If you're very comfortable in your own skin, sure, you'll date a 35-year-old guy. Why not?" says Corso.
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Just 10 years ago, the same poll found that 41 was the ideal age. So what's changed? "A lot has to do with the boomers themselves...the graying of America," says Corso. Also, that the past few years have been rough economically, but by now many Americans in their 50s might feel like they're back on track financially and professionally.
For men, the ideal age is 47, the poll says.
The perfect age also varies slightly depending on the region in which you live. On the East Coast, 53 is the perfect age. It's 51 in the South, 50 in the Midwest, and 47 in the West. Those with kids say 47 is the perfect age, and those without kids would prefer to be 53.
When you don't account for gender, 50 is the ideal age if you could live forever in good health, the poll says.
And despite Republicans and Democrats not being able to get along in Washington, D.C., they both agree that 53 is perfect. Independents, however, prefer to be 46.
Being in your 50s "doesn't have the same stigma as it did years ago," says Corso.