Do you worry about your weight?

I'm currently kinda sorta dieting. I eat what I want up to a certain hour, after that I have to pull out the rabbit food. I definitely have the fat gene in my family. All of my uncles hit a certain age and they balloon out and I'll be damned if I let that happen to me. I can't be the sexy, fat R&B guy.

What exercise do you take?

I go to the gym every morning to do free weights and cardio, then I'm on stage for 50 minutes a night, sweating hard. That's pretty much all the exercise I need. I'm not in top shape right now, but I'm damn near it.

How do you relax?

Writing, not necessarily writing a song, just writing in general. I have little notebooks that I carry around with me; some of them have songs in them, some just have random rants. It keeps your song-writing sharp.

How much do you drink?

I stopped drinking in September last year. I couldn't go out to a club and have fun without having a drink and I don't like feeling like something else is in control of me like that. It's actually a lot more fun sober.

Attitude to smoking?

Not a smoker, never been a smoker, don't condone it whatsoever. I'm a singer, so that's like kryptonite to me. I tried marijuana when I was younger because all of my friends smoked, but it's not for me.

Are you happy?

I'm the happiest person you'll ever meet. The glass is always half full. I look at my life and think, "I'm 29 years old and I get to do what I love for a living" - it's like letting a kid play video games all day long and then paying him to do it.

Is sex important to you?

Of course. It's like jump-starting your engine.

How do you feel about cosmetic surgery?

Each to his own. I personally feel that God created everybody the way he created them for a reason. For me? There's nothing I'd change. I would just go ahead and get old, get crow's feet and let stuff sag - that's what's supposed to happen.

• Ne-Yo's album Year of the Gentleman is out now