Mark Wahlberg shed almost 30kg for the title character in Rupert Wyatt's remake of 'The Gambler', it has been revealed.

The 'Ted' actor said that he was on a liquid diet for about a month under the watchful eye of doctors and continued to lose weight during the shoot, News.com.au reported.

He was relieved once he could start eating again and he believes it is lot easier to gain weight than to lose it, as he could see a remarkable rapid transition when he was getting back to his normal size, he added.

The 43-year-old actor plays the role of a literary professor whose gambling addiction sees him run afoul of gangsters in the upcoming movie.