Willis McGahee -- Fart-Sniffing Has Health Benefits? I'll Self-Medicate!

Everyone's talking about the new medical study that suggests sniffing farts could have serious health benefits -- but NFL running back Willis McGahee says he'll ONLY accept prescriptions ... from himself.

The study was conducted by the University of Exeter -- which says one of the chemical compounds found in flatulence can actually help prevent ailments like diabetes, strokes, heart attacks and dementia ... when used in small doses.