We all love a good celebrity transformation, and lately it seems that some stars have been slimming down! Whether it be for a specific role or just getting more fit, here are some men that have noticeably changed their physique recently.

Jason Segal after weight loss (Tumblr)

Known as Marshall in "How I Met Your Mother," Jason Segal has been seen as a giant teddy bear. However, he stepped out looking fit this summer. According to Segal, he's been leaning out for his next movie, "Sex Tape" costarring Cameron Diaz. He said the trick to his weight loss was living healthy: eating right, exercising, the works. 

Jonah Hill after huge weight loss (TwitPic)

Jonah Hill

The "Superbad" star was quite the chubby one back in the day. It wasn't until a year later he slimmed down drastically, catching everyone's eye. Though it looks like he's put on some weight in recent times, Jonah Hill has definitely gotten everyone's attention with his weight loss. 

Rob Kardashian gets fit again (TwitPic)

Rob Kardashian

It appeared that of all the Kardashians, Rob was the one who was not phased by his less fit physique. The only guy in the family, Rob's sisters all have emphasized the importance of weight loss and fitness. Now he's working out more and trying to cut out alcohol, looking to move in a healthy direction.

Josh Peck chisels his body (Tumblr)

Josh Peck

Always the funny child star on television, the "Drake and Josh" star was known as the hefty kid. Everyone can easily recognize Josh Peck for his heavier form since he first appeared on Nickelodeon's "All That" and "The Amanda Show." Peck began to shed off his baby fat as he got older, working for a healthier and happier version of himself. Now he is looking more handsome than anyone would have ever guessed!

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