Matthew Lewis, who caused a frenzy when photos of his buff, new look surfaced on Twitter, is going one step further to show off his recent transformation. In the new issue of the British gay magazine, Attitude, the actor strips down to his skivvies to give fans a full view of his six pack -- and more. 

Though, the new bod doesn’t come without effort. The 25-year-old actor explains that he gave up alcohol in order to portray a triathlete in the new film, "Me Before You," co-starring Emilia Clarke ("Game of Thrones") and Sam Claflin ("The Hunger Games" series).

“I spoke to the director and I said it’d be nice to get into the mindset of someone like that, because he’s not drinking alcohol, he’s just eating salads all the time, and I was very interested to know where you go to in your mind to have that level of commitment,” Lewis says.“So I sort of gave up alcohol -- I say sort of, I have given up alcohol.”

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He also reveals that his diet has taken a hit.

“I’m off sugar and I can’t really eat carbs. I really wanted to see if I could stick to such a strict regime, and to really understand what it’s like to have a goal like that and really 110 percent go for it,” Lewis says. “I mean I’ve always been a bit of a sports enthusiast anyway, I love the gym and all that stuff, but I can’t wait for a pint of lager, I tell you that!The pizza and beer will definitely be making a comeback over the summer.”

Well, Potter fans rejoice because the hard work has paid off!