How to read a supplement label
Compare serving size, ingredient amount and package cost on the same basis
Checked on 2 November 2026Begin with the serving
Find the number of capsules, scoops or drops in one serving and the number of servings in the package. Net weight alone does not establish the number of comparable portions.
Separate the quantities
Elemental magnesium differs from compound weight. Total fish oil differs from EPA plus DHA. A collagen scoop can include vitamins and flavouring. For probiotics, read strain identifiers and the timing of the CFU guarantee.
Read the rest of the formula
Check declared allergens, sweeteners, additional nutrients, storage and expiry. A manufacturer sample label is useful for comparison but must be checked against the actual product you receive.
Use sources for their actual purpose
Manufacturer labels describe declared composition; they do not independently prove effectiveness. The NIH supplement overview ↗ explains why supplements require care and may interact with medicines.
Cost per serving calculator
Use the same currency for every amount — this tool does not convert currencies or recommend a dose
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Information for comparison, without individual dosing advice. Supplements do not replace a varied diet or prescribed treatment. Discuss use with a doctor or pharmacist.