Glossary
This section translates recurring supplement terms into plain English. It is meant to reduce the friction created by label jargon, clinical-sounding wording, certification language, and marketing phrases that make ordinary supplement questions feel harder than they need to be.
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- Bioavailability Useful when supplement-form marketing leans on absorption claims and you want to know when that actually changes the decision.
- CFU Useful when probiotic marketing is leaning heavily on a giant number and you want to know what that number can and cannot tell you.
- Daily Value Useful when %DV looks authoritative but you are not sure how much it should shape the buying decision.
- Elemental calcium Useful when calcium labels look stronger or weaker than they really are because the compound and the actual mineral amount are not the same thing.
- Elemental magnesium Useful when magnesium labels list glycinate, citrate, oxide, or threonate and you need the actual magnesium amount.
- Excipient Useful when the label question is really about fillers, binders, coatings, or why non-active ingredients still affect the product experience.
- Heavy metals Useful when a supplement page mentions lead, cadmium, mercury, arsenic, contaminants, COAs, or clean-label testing.
- NSF Certified for Sport Useful when an athlete, coach, parent, or drug-tested competitor needs a stronger quality signal than a generic tested claim.
- Other Ingredients Useful when the confusing part of the label sits in the ingredient list rather than in the main Supplement Facts box.
- Proprietary blend Useful when a label groups ingredients together and you want to know what is still visible and what is being hidden.
- Serving size Useful when a label hides the real dose behind two capsules, one scoop, or several gummies.
- Third-party testing Useful when a label says tested, certified, verified, or clean and you need to know whether that claim is specific enough to trust.
- Upper limit Useful when a nutrient page mentions too much vitamin D, zinc, magnesium, selenium, iron, or another nutrient.
- USP Verified Useful when a label uses the USP mark and you want to know what it does and does not prove.
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Supplement glossary definition
The Supplement Explained glossary is a plain-English reference for label terms, supplement-form wording, dose math, testing claims, safety-limit language, and marketing phrases that often confuse shoppers. Each term is designed to answer the definition first, then show where the term matters on a real supplement label.
How should you use this glossary?
Use it when a term on a label changes the buying decision: serving size changes dose math, CFU changes probiotic comparisons, elemental magnesium changes mineral comparisons, third-party testing changes quality confidence, and upper limit changes safety context.
What makes a glossary term useful?
A useful definition should be short enough to understand quickly, specific enough to compare products, and connected to the broader guide where the term affects real supplement choices.