"When you're in your mid-20s, you go, 'Oh, I'm not old yet, I'll be old when I'm in my late 20s,'" he says. "Then when you're in your late 20s, you're like, 'I'm not old yet, I'll be old when I'm in my 30s.' And I think when I hit 31, I [said], 'Alright, I can't (bleeping) fool myself anymore. I'm an adult.'"
In Braff's new movie, "The Last Kiss," that same realization is knocking on the door for Michael (Braff) and his friends. They're all 29 and, to varying degrees, are afraid that turning 30 will end their carefree glory days.
Braff, who is currently single but used to date actress-singer Mandy Moore, says that he can relate to societal pressure about when "adult" life is supposed to start.
"I think society says when you're 30 or 31, you're supposed to think about marriage and settling down and having kids," he says. "Guys can push that a little bit later than girls can because of their maternal clock, but you can't help but think about it, and think about, you know, 'Who do I want to be? Do I want to have kids? Do I want to have a family? When should I start that?'
"And if you're in a relationship and you're in love, you can't help but think when you're 31, 'Is this the one I'm going to spend the rest of my life with?'"
Marriage isn't a popular topic of discussion for Braff's character in "Kiss." Michael loves his pregnant girlfriend, Jenna (Jacinda Barrett), but is tempted by college student Kim (Rachel Bilson). Much of Michael's fear of settling down comes from the lack of stable marriages around him, including that of his buddy, Chris (Casey Affleck).
Braff says that with today's high divorce rate, many people deal with fear of commitment.
"Our generation grew up with most of our parents getting divorced, and we can't help but have a cynical view when we're honest with ourselves whether marriage works and whether you can spend your entire life with one person," he says.
"Kiss," with its look into life's more difficult questions, seems to have come along at the right time for the New Jersey-born, Northwestern University-educated Braff. The actor has certainly had to ask himself tough questions regarding the direction of his career after the popularity of "Garden State," his first big screen lead and his feature debut as a writer-director.
"I think the best thing to do is for me to be honest with my fans and say, 'Don't expect there to be "Garden State 2," it's not going to happen ,'" he says. "I'm not going to be the guy that makes generational transition movies; that's not going to be, like, my calling card. It just so happens that my first two are that."
Right now Braff's thinking about his NBC sitcom "Scrubs." He says his contract is up after the upcoming season that he is working on now, but he hasn't decided if it will be his last. The new season, Braff says, will feature "a lot of babies flying around" and "a show about abortion that I'm sure will generate a lot of mail."
As for the humor of the show, the formula is simple: "At this point we just do what makes us laugh," he says.
For his next big screen project, Braff won't be going for laughs. He plans to direct, write and star in "Open Hearts," a remake of a Danish film about a woman coping after her husband is paralyzed in a car accident. Before that, he'll hit theaters in the workplace comedy "Fast Track."
Braff wouldn't confirm that he plans to revive the crime-solver Fletch in "Scrubs" director Bill Lawrence's "Fletch Won" film.
"No updates," Braff said. "Bill's going to do it and I gotta talk to Uncle Harvey [Weinstein, the producer] about it and see if he can work something out."
On top of his already busy schedule, Braff tries to find time to approve loads of friend requests on his MySpace page. He currently approaching 70,000 friends on the site. Eventually he wants to tackle things on his "life to-do list," he says, including learning to horseback ride, playing the drums and flying a plane (He is taking flying lessons).
But most of the time, "I think I live a normal life of a guy who works ridiculous hours at his job and comes home and watches TV," he says.
That is, a normal guy who's a TV and movie star and has built a community of loyal and, apparently, romantically interested fans with no qualms about commitment.
"I do get quite a few marriage proposals," he says. "I'm very flattered, but ironically, I'm not ready to get married."