How to read a supplement label

Every supplement sold in the United States carries a Supplement Facts panel in a standard format. Once you know where to look, a label tells you almost everything you need.

Serving size and servings per container

Everything on the panel is per serving, and a serving is not always one capsule. If the serving size is two capsules and the bottle holds 60, that is 30 servings, not 60. Check this first; it is where most surprises hide.

Amount per serving and % Daily Value

Each nutrient is listed with its amount and, where one exists, the percentage of the Daily Value (%DV) for adults. 100% DV means one serving provides the reference daily intake for that nutrient. A dagger (†) means no Daily Value has been established, which is common for ingredients like amino acids, herbs and probiotics.

The form matters

The same nutrient can come in different forms, shown in parentheses: vitamin D3 (cholecalciferol), magnesium (as bisglycinate chelate), vitamin B12 (as methylcobalamin). Forms differ in how they are made, how they are absorbed and how they sit in the stomach. The label should always say which form you are getting.

Other ingredients

Below the line you will find everything else in the product: the capsule material, fillers, flow agents, flavors and sweeteners. A short list is usually a good sign. This is also where you find out whether a capsule is gelatin or vegetable-based.

Allergen statements

Products that contain milk, egg, fish, shellfish, tree nuts, peanuts, wheat, soy or sesame must say so. Whey protein contains milk; fish oil contains fish. If you have an allergy, read this line every time, because formulas change.

Lot number and dates

The lot number identifies the production run your product came from; keep it if you ever need to contact the company. The “best by” date tells you how long the product is expected to keep its labeled amounts when stored as directed. Store products as the label says, usually in a cool, dry place with the lid tightly closed.

Directions and warnings

The directions tell you how much to take and when. The warnings tell you who should check with a healthcare provider first, typically anyone pregnant or nursing, taking medication or managing a condition. “Keep out of reach of children” appears on nearly every product for good reason.

The FDA statement

Supplements that describe how a nutrient supports normal body functions carry the statement: “These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.” It is required by law and is a useful reminder: a supplement is a food, not a medicine.

This guide is general information, not medical advice. Talk to your healthcare provider about which products, if any, are right for you.