Justin Bieber has opened up about growing up under the public spotlight.

The 21-year-old shot to fame as a teenager after being spotted on YouTube.

However, his behaviour has often come under scrutiny, with the singer arrested last year for DUI.

Speaking in the April issue of Men's Health, Bieber admitted that he lost out on part of his natural growth due to fame.

He said: "I had to grow up so quick. And it was almost like I grew up for the public but I didn't necessarily grow up.

"There were things I had to do, as far as the way I had to make relationships, and conversation, but as far as actually growing up, there were a lot of things I missed out on."

The Canadian added in the interview that he has matured over the last year.

The April issue of Men's Health will go on sale in the US from March 10.

Follow us: @Pressparty on Twitter / Pressparty on Facebook.

Watch Justin Bieber performing live below: