Rob McElhenney gained fifty pounds to play Mac this season. Why? For the sheer comedy of playing his character as a fat guy. “It’s been disgusting to watch him go through with this adventure,” said Charlie Day. “We were a little on the fence about it for his own personal health and safety,” he added, “but it has definitely made Mac a lot funnier.”

http://www.screenjunkies.com/tv/tv-news/its-always-sunny-in-philadelphia-season-7-preview/

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