Cayenne pepper has powerful therapeutic effects. It helps with migraine, allergies, digestive issues, bad breath and joint pain. Moreover, it’s been popular as a weight-loss supplement, ever since the Master Cleanse diet offered it as a part of its recommended formulation, along with lemon juice and maple syrup. Cayenne pepper can only help you lose weight through bumping up your metabolism slightly, though. It doesn’t do enough to deserve a label as a weight-loss supplement.