Supplement Label Glossary

Short answer: on a Canadian supplement label, the NPN shows Health Canada has licensed the product, the medicinal ingredients are the active ones, and units such as mg, mcg and IU measure different things. This glossary explains the terms you will see.

Licence numbers

NPN (Natural Product Number)
An 8-digit number Health Canada issues when it licenses a natural health product after assessing its safety, efficacy and quality. It appears on the label with the prefix "NPN". You can look it up in Health Canada's Licensed Natural Health Products Database. See our guide to checking an NPN or DIN.
DIN (Drug Identification Number)
An 8-digit number on non-prescription and prescription drugs that Health Canada has authorised, such as acetaminophen or ibuprofen products.
DIN-HM
The number on licensed homeopathic medicines, in place of an NPN.

Ingredients

Medicinal ingredients
The active ingredients, such as vitamin D3 or magnesium. The label lists the amount of each per dosage unit (per capsule, tablet or serving).
Non-medicinal ingredients
Everything else: capsule shells, fillers, binders, flavours, colours and preservatives. Check this list if you have an allergy or avoid certain ingredients such as gluten or gelatin.
Elemental vs compound weight
A mineral supplement may state the weight of the whole compound (for example, magnesium citrate) or only the mineral inside it (the elemental magnesium). These numbers are different. When comparing products or checking against a limit, use the elemental amount where the label gives it.
Standardized extract
A plant extract made to contain a stated amount of a marker compound. The label should say what the extract is standardized to.

Units

mg and mcg (or µg)
A milligram (mg) is one-thousandth of a gram. A microgram (mcg) is one-thousandth of a milligram. 1,000 mcg equals 1 mg, so mixing them up is a 1,000-fold error. Always check the unit.
IU (International Unit)
A unit based on biological activity, so the conversion to mg or mcg differs for each nutrient. For vitamin D, 1 mcg equals 40 IU. Many labels now show mcg, sometimes with IU in brackets.
CFU (colony-forming units)
The number of live bacteria in a probiotic. A higher count is not automatically better; the strain matters. See Probiotics 101.

Canadian Dietary Reference Intakes (DRIs)

RDA (Recommended Dietary Allowance)
The daily intake that meets the needs of nearly all healthy people in an age and sex group.
AI (Adequate Intake)
Used when there is not enough evidence to set an RDA. It is an estimate based on what healthy groups typically consume.
UL (Tolerable Upper Intake Level)
The highest daily intake unlikely to cause harm for most people. Count all sources, including food, fortified foods and every supplement you take. Some ULs apply only to supplement or fortified sources, so check the Health Canada table.

Health Canada publishes the values in its vitamin and mineral (elements) tables.

Forms and dates

Softgel
A soft, sealed capsule, usually filled with an oil or liquid. Common for fish oil and vitamins A, D and E.
Vcap (vegetarian capsule)
A hard capsule made from plant material (often hypromellose) instead of gelatin. Check the non-medicinal ingredients to confirm.
Best-before and expiry dates
Natural health product labels show an expiry date. Store the product as the label directs and do not use it after that date.
Recommended use and cautions
Health Canada requires natural health product labels to state the recommended use, dose and any cautions or warnings. Follow them, and ask a pharmacist if you take other medicines.

Related

When to see a doctor or pharmacist

Ask before starting a supplement if you are pregnant or breastfeeding, have a medical condition, or take prescription medicines. Stop and get medical help if you have a reaction.

Sources

This glossary is general information, not medical advice.