Chrissy Metz Defends Chris Sullivan's 'This Is Us' Fat Suit

"He does understand the plight of being overweight."

Chrissy Metz is addressing some fans' criticism of her This Is Us co-star Chris Sullivan's use of a fat suit on the show.

The 36-year-old actress appeared on Watch What Happens Live with Andy Cohen on Thursday, and insisted that Sullivan was the right person to play her character Kate's love interest, Toby, on the show. She also says Sullivan, 36, has previously been heavier, and understands what it feels like to be overweight.

"I just feel that we tested a lot of people that were bigger -- and I get it, the authenticity is kind of ruined by that -- but Chris has been heavier, and I think he does understand the plight of being overweight," Metz told host Andy Cohen. "Also, he was the best man for the job, and people wear prosthetics all the time. This just happened to be weight as opposed to, like, a nose or a chin."

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Metz referred to her own use of prosthetics when she played Ima Wiggles on American Horror Story: Freakshow.

"It's just kind of the name of the game," she said.

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When ET recently sat down with the actress, she admitted that she wishes future episodes of the NBC hit would be less "tear-jerking" and more comedic.

"I'm not always drained, but [sometimes] it's like, 'Can we do a musical episode?'" she joked. "Can we crossover with Will & Grace?"

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