The FDA does not regulate supplements. They are barely subjected to government scrutiny due to a law passed in the 1990s. The claims that include vague words like "promotes", "maintains" and "supports" are legal as long as manufacturers attach a disclaimer that reads: “These statements have not been evaluated by the Food and Drug Administration. Our product is not intended to diagnose, treat, cure or prevent any disease.”
However, target consumers are starting to become educated and care enough to call the beauty industry out on their wild claims.