Zayn Malik has been "partying too much".
The Pillow Talk hitmaker - who recently pulled out of the Capital FM Summertime Ball due to anxiety issues - is doing his best to eat healthily after his lifestyle began taking its toll on his health.
He said: "I've not been feeling too well recently because I've been partying too much and not looking after myself and eating enough food. I'm just trying to take care of myself."
The former One Direction hunk admits the reaction to his solo material from his fans has been "overwhelming".
He told Paper magazine: "There've been a few moments where I've been really taken aback...
I feel like everybody looks for some sort of approval from some form in their life, and my fans are my approval. It's a sense of achievement that you can't really explain."
The 23-year-old singer - who is dating model Gigi Hadid - was unable to dye his hair or sport facial hair during his time in One Direction because it made him look "old" so he is thrilled he can now grow a beard without getting into trouble.
He said: "Facial hair was a weird thing.
"I think it's 'cause I just looked old. And they didn't like that. [And] I always wanted a beard! I think every dude does when they're young.
"Seeing Al Pacino in 'Carlito's Way' - I needed the goatee after that. I was like, 'I wanna be Al Pacino.' I've always been obsessed with that, and I had to shave it off. I used to get a bit sad."
Zayn's London home boasts its own pub, which he based on one of his favourite movies, Disney's Pirates of the Caribbean.
He said: "I love the [movie's] aesthetic and how well it's done.
"I feel like it's really authentic to pirate times...
"Like I know anything about 'pirate times.' I guess I just love it. I'm a big kid."
- Bang! Showbiz