Hader opened up about the weight gain in a new interview with 'The Hollywood Reporter.'
Bill Hader is getting real about gaining weight.
"To know that I’ve grown as a filmmaker is really rewarding," Hader said when asked what he's learned about himself over the course of the show's four seasons.
Outside of the show, one of the biggest things Hader said he learned, was that he puts on weight much faster than he did at the show's start.
"But I also know that I’m 45 and I put on weight way faster than I used to. That’s what I really learned, that I’m suddenly 25 pounds overweight," he quipped. "How the hell’d that happen? I've learned I can't eat sweets the way I used to."
Hader continued, reflecting on his final season weight gain, "I think it was toward the end of the season that the costume designer was like, 'I think you need to wear bigger clothes. You're wearing a large, and, well … We’ve got to go up a size, or three.' Great!"
Hader previously spoke about gaining weight while making Barry in an April conversation with Access Hollywood, telling the outlet he was "stress eating" during filming.
"I don't train at all. I eat a lot of doughnuts and stress," Hader said when asked if he trained for Barry's action scenes. "I put on... between episodes three and four... I put on 25 lbs. from sheer stress eating. None of that is for the character. That is purely a guy during all the episodes and writing everything, and just stress eating like crazy. I'm in the process of trying to lose it."
The show, which is up for 11 Emmy nominations this year, including four for Hader, was created by the Saturday Night Live alum and Alec Berg. The award-winning series sees Hader as the titular character, a former U.S. Marine who worked as a hitman before he stumbles into an acting class taught by Henry Winkler's Gene Cousineau.
While speaking to the ET's Denny Directo at the show's season 4 premiere in Los Angeles in April, Hader said he felt satisfied that he and the writers were able to end the dark comedy on their terms.
"Oh yeah, it feels good," Hader said. "It's nice to write, 'The End,' on the thing, but it's going to be sad to say bye to everybody. That's the hardest part of it."
The show's fourth season wrapped up in May, with all four seasons of the series available to stream on Max.