SEINFELD STAR SHEDS 100 LBS!

FORMER fattie Wayne Knight - who played Seinfeld's portly postman nemesis Newman on the hit '90s series - dropped more than 100 pounds after a doctor warned he was eating himself to death!

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Knight, 69, was smashing the scales at more than 300 pounds when a cardiologist told the 5-foot-7 funnyman he was courting diabetes, heart disease and strokes! "That was the ultimate wake-up call," a source dishes.

According to Knight, he's been overeating since childhood, once joking, "I used to get a tan from the light in the refrigerator."