Reference
Glossary
Supplement labels are written in a vocabulary designed to sound like evidence. Here is what each term actually means, and which ones mean nothing at all.
- Bioavailability
How much of an ingredient your body can actually absorb and use, as opposed to how much is printed on the label. Curcumin is the clearest example: plain turmeric powder is absorbed so poorly that a large dose can still do nothing, which is why formulations use enhanced delivery systems.
Bioavailability is one of the reasons dose alone is a bad way to compare products. Two gummies listing the same milligram number can deliver very different amounts.
Where this comes upMagnesium →Joint Comfort →Omega-3 →
- Certificate of analysis (COA)
A lab document reporting what a specific production batch was found to contain. A useful COA names the testing laboratory, gives the batch or lot number, states the method used, and reports the actual measured amounts rather than the label claim.
A COA you cannot read is not verification. We count a COA when the brand publishes it and it comes from an ISO 17025 accredited laboratory.
Where this comes upCreatine →Gut Health →Metabolic Support →
- Creatine monohydrate
The most studied sports supplement there is, used to support strength and power output during short, intense effort. The research base is built almost entirely on the powder at roughly 3 to 5 grams a day.
It is also the ingredient with the worst record in gummy form. Creatine degrades into creatinine in moisture and heat, and independent testing has repeatedly found gummies containing far less creatine than claimed, or effectively none.
Where this comes upCreatine →
- Elemental magnesium
The amount of actual magnesium in a compound, as distinct from the weight of the whole compound. Magnesium citrate is only around 16 percent magnesium by weight, so 500 mg of magnesium citrate is not 500 mg of magnesium.
Labels are supposed to list elemental magnesium, but marketing copy often quotes the compound weight. When a gummy quotes a large number, check which one it means.
Where this comes upMagnesium →Stress & Calm →Sleep →
- Gummy matrix
The pectin or gelatin base that carries the active ingredient. It is the reason gummies fail testing more often than tablets: the ingredient has to survive manufacturing heat, then sit in a sugar and water environment for the life of the product.
Some ingredients tolerate this well. Vitamin D and B12 are stable. Creatine, probiotics, and fish oil are much harder to keep intact.
Where this comes upCreatine →Omega-3 →Gut Health →
- Metabolic support
A marketing phrase, not a medical one. Because supplements cannot legally claim to treat obesity or diabetes, products aimed at weight and blood sugar are sold as supporting metabolism instead. The phrase has no regulated definition and no required evidence behind it.
In gummy form it usually means apple cider vinegar, chromium, or cinnamon. The honest summary is that the effects documented in the research are small, and the doses that produced them are often larger than a gummy delivers.
Where this comes upMetabolic Support →
- Prenatal vitamins
A multivitamin formulated for pregnancy and the months before it, built around folate to reduce the risk of neural tube defects, plus iron, iodine, choline, DHA and vitamin D.
Gummy prenatals share one structural problem: iron tastes metallic and does not work in a gummy, so nearly all of them leave it out. Whether that matters depends on your iron status, which is a blood test question rather than a label question. Prenatal choices belong with a clinician, not a review site.
Where this comes upPrenatal →
- Proprietary blend
An ingredient list that gives a combined weight for several ingredients without saying how much of each is present. It is legal, and it makes the dose impossible to evaluate.
A proprietary blend that hides the dose of the main active ingredient is an automatic disqualifier in our rankings.
Where this comes upMetabolic Support →Energy →Hair, Skin & Nails →
- Structure/function claim
The kind of statement a supplement is allowed to make: that it supports, maintains, or helps with a normal body function. "Supports immune function" is a structure/function claim. "Prevents colds" is a disease claim and is not permitted.
Any gummy that makes a disease claim is telling you it is willing to break the rules it can be checked against, which is a reasonable signal about the rules it cannot.
Where this comes upImmune Support →Metabolic Support →Joint Comfort →
- Third-party tested
The single most abused phrase in the category. Used honestly it means an independent laboratory confirmed the contents. Used as it usually is, it means nothing verifiable, because no lab, method, batch or result is named.
We treat the phrase as worthless on its own. It counts only when there is a certification body or a published COA behind it.
Where this comes upCreatine →Gut Health →Immune Support →
- Tolerable upper intake level (UL)
The highest daily intake likely to pose no risk of harm for most people. It is a ceiling, not a target.
It matters most for the fat-soluble vitamins, which accumulate, and for children, whose limits are much lower than adults'. Gummies make exceeding it easier than pills do, because they taste like candy.
Where this comes upVitamin D →Kids' Multivitamin →
- USP Verified
A certification from U.S. Pharmacopeia confirming that a product contains the listed ingredients in the listed amounts, does not contain harmful contaminants, and was made under good manufacturing practices. It is the strongest widely available mark in the supplement aisle.
One caveat specific to this format: USP holds gummies to looser potency tolerances than tablets. A USP Verified gummy is a far better bet than an unverified one, but the seal is a floor rather than a guarantee of precision.
Where this comes upSleep →Magnesium →Vitamin D →Prenatal →
- NSF Certified
An independent certification confirming label accuracy and contaminant screening, with an additional programme, NSF Certified for Sport, that screens for substances banned in competition.
Roughly comparable to USP in rigour. The two rarely overlap, so the practical question is whether a product carries either.
Where this comes upSleep →Stress & Calm →Energy →