Actress Kristen Johnston is struggling to gain weight again after a burst ulcer turned her skinny overnight - because the illness has robbed her of her hunger for food.

The 3rd Rock from the Sun star was last year (08) forced to deny rumors she was suffering from an eating disorder, after she was snapped looking skinny, revealing she fell ill during a run on London's West End stage in Love Song and dropped 40 pounds (18 kilograms) in weight in a London hospital.

Six months on, the statuesque star claims she's finding it impossible to bulk up to her former size, because she's never hungry.

Johnston, 40, tells People magazine, "The problem is, my stomach no longer indicates to me whether it's hungry. When food is in front of me, I eat it, but I'm never hungry. Ever. I went to the doctor about it. He says my stomach will eventually get back to normal." (IG/PE/MT)

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