Thinner (1996)

In the shadow of an eerie enchantment, a fat lawyer undergoes a disturbing metamorphosis, shedding pounds rapidly under the spell of an aged gypsy. Desperate to shatter this curse, he enrolls his criminal associates' help from the underworld. Racing against mortality's grip, the lawyer battles time as his body withers away. This narrative is derived from Stephen King's novel of the same title, if you are a fan just do not miss that.