How do I read a supplement nutrition panel?

Five checks cover most of it. One: serving size — every other number depends on it, and "protein per serving" means little until you know how big a serving is. Two: grams of protein per serving, the honest figure versus front-of-package math. Three: the sugar and sugar-alcohol lines, listed separately from total carbs. Four: whether it is a transparent ingredient list or a proprietary blend that hides doses. Five: any third-party testing or certification. Do those, then compute dollars per 20 grams of protein, and the marketing loses its grip.