After a series of weight fluctuation, Jonah Hill surprised his fans after showing a fitter than ever body this weekend.

The 33-year-old actor shared in the past about his weight loss regimen which seems not to be an easy one. He admitted that the culprit for his weight gaining back is when he drinks beer—something he has a hard time going without.

“I went to a nutritionist and I said, ‘I’ll lose weight, I’ll eat healthier or whatever, but figure out how I can drink beer,’” he previously revealed. “It’s so annoying because if I don’t drink beer, I get really, really thin. Then when I drink beer, I get a little bigger.”

Hill also credits his recent weight loss transformation to some advice from his friend and “21 Jump Street” co-star, Channing Tatum.

“I wanted to get in better shape, so I called Channing Tatum and said, ‘Hey, if I ate less and go to a trainer, will I get in better shape?'” Hill said during an interview on “The Tonight Show.” “Yes, you dumb mother****er, of course you will. It’s the simplest thing in the entire world.”

Currently, Hill is under a “Japanese diet” and according to him, it is the most effective diet he tried among the other plans he had been into.