Research indicates that meat consumption and inflammation go hand-in-hand, which is a bummer for your skin. Inflammation breaks down collagen and elastin, the building blocks of a youthful complexion. As for milk, it often comes from pregnant cows—meaning you’re gulping down cow hormones, which can bring on the zits. And both milk and meat contain an amino acid called leucine that may ramp up oil production in your skin, causing pimples. Yick. Veggie burger anyone?

MORE: What Going Vegan Can (and Can’t) Do for Your Skin