Here’s some simple math that many people still can’t seem to grasp. You’re in the gym for only an hour or so each day, leaving another 22–23 hours in which muscle growth depends solely on what goes in—or stays out of—your piehole. So why is the nutrition side of the mass-gaining equation often marginalized? It’s probably because a bench press is a lot sexier than a spinach salad.

But if you want to take your physique from string bean to Mr. Clean, certain dietary principles need your utmost attention. These 12 get-big eating tips will help you build the body you’ve always yearned for without blowing up like the Pillsbury Doughboy.