The front of a supplement bottle is advertising. The back is the document that matters. Yet most buyers read the front, glance at the price, and never get to the fine print where the useful information lives. The fine print is not there to confuse you. It is there because the law requires the brand to disclose things it would rather not shout about, and learning to read it takes about ten minutes.

Start with the Supplement Facts panel. This is the boxed table that lists every ingredient and its amount per serving. Two things matter here. First, whether each ingredient has a named amount or is buried inside a proprietary blend. A blend lists a total weight for several ingredients together, which means you cannot tell how much of any single one you are getting. A fully disclosed label names each amount separately. Second, check the serving size against the directions.…