A lot has been written about happiness - and the Journal of Happiness Studies chimed in today with a study says that woman are happier than men - but only until their late 40s. Then, as CBS News correspondent Cynthia Bowers reports, everything changes.

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For anyone who doesn't understand the results of the study, take a look at Exhibit A: Hugh Hefner, a man who gets happier as he gets older - and his girlfriends get younger.

As the advice columnist for the Chicago Tribune, and as a woman of a certain age herself, Amy Dickenson understands that middle age can be a turning point.

"The most we can hope for in terms of a compliment is for someone to say that you look good for your age, you know?" Dickenson said. "That's not so good!"

The study, which analyzed data from 47,000 people, considered happiness levels of men and women. It found in their 20s, women are happier than men. Researchers blame that on young men's lackluster love lives and low-paying first jobs, Bowers reports.

The gap closes with age - and by 48, men are happier. The study suggests it's because by then men are married and better off financially.

But the actual survey the study was based on was headed up by Tom Smith at the University of Chicago. It only asked women how happy they are, and just like a lot of men, didn't bother to ask them why.

"We think we have a good understanding of why women start off happier - they make that transition to adulthood much easier than men," Smith said. "Uh, it's less clear why they lose the advantage over men."

In a personal observation, Bowers had her own thoughts on the matter: "Hello … it's because we hit 48! Not only are we raising kids, and worrying about aging parents, we're worrying about aging us. All the sudden we realize that even with Botox, and body shapers, we'll never look like we used to."

The hit movie "Knocked Up" showed that very fear - that dreaded day when age becomes the enemy.

"Men! I get worse-looking and he gets better-looking," one character says.

Buried deep in this study is the best part, though, and that's this: Older men - and women! - claim to be the happiest of us all.

Researchers say by then we've realized what's important in life. In other words: with age comes maturity - and that's a good thing.