Thinner (1996)

Barrister Billy Halleck, complacent and considerably overweight, faces an unimaginable reckoning when a vengeful Romani elder curses him. Suddenly, Halleck experiences rapid and terrifying weight loss, a horrifying transformation hinted at in the single word, "Thinner." Desperate, he turns to his dubious connections within organized crime, seeking leverage to break the hex. But time is a relentless enemy as the curse accelerates, pushing Halleck toward a gruesome demise. The lawyer must confront his past actions before he fades away entirely.