Chrissy Metz Fighting For Every Breath!

Doc warns 403-lb. TV sensation must diet – OR DIE!

PORKY This Is Us star Chrissy Metz has ballooned to 403 pounds — and pals are begging the tub-o-lard to slim down!

“Chrissy can hardly walk a red carpet without breaking a sweat and she tires very easily,” dishes an insider.

“There’s a genuine fear she’s putting herself at risk of a heart attack — and friends are urging her to lose 100 pounds, at least!”

The five-foot-five actress’ extra bulk nearly ruined her live singing debut with Carrie Underwood and other stars at April’s Academy of Country Music Awards!