Short answer: a proprietary blend lists ingredients in descending order by weight and gives one combined total. Individual doses are not disclosed, so you cannot tell whether an ingredient is present at a studied dose or as a trace. That is the point of the format.
Proprietary blends are legal, common, and the most effective way a formula can look impressive while telling you almost nothing.
What a blend must disclose
A proprietary blend has to list every ingredient it contains, in descending order by weight, and give the total weight of the blend. It does not have to disclose how much of each individual ingredient is present.
So a 500 mg blend of eight ingredients could be 490 mg of the cheapest one and 10 mg spread across the seven the marketing is built on. Nothing on the label would distinguish that from an even split.
The fairy dusting pattern
‘Fairy dusting’ is including a well-known ingredient at a dose far below what was studied, purely so it can appear on the label. A blend is the ideal vehicle for it because the individual amount never has to be shown.
- A long ingredient list inside a small total weight is the clearest signal — the arithmetic simply cannot support meaningful doses of everything listed.
- Ingredients near the end of the list are, by definition, present in smaller amounts than those before them.
- A branded, trademarked ingredient inside a blend still tells you nothing about its dose.
How to read one anyway
- Compare the blend total against the studied dose of the first ingredient. If the total is smaller than the single studied dose of the lead ingredient, everything after it is a trace.
- Count the ingredients. Divide the total by the count for a best-case average, then remember the real distribution is front-loaded.
- Look for anything disclosed outside the blend. Manufacturers usually break out the ingredients they are willing to be judged on.
When a blend is not a red flag
Blends do have legitimate uses — genuine formulation trade secrets exist, and flavour systems are a real example. The problem is not the format itself but its use to obscure doses in categories where dose is the whole question.
Frequently asked questions
Are proprietary blends legal?
Yes. Listing ingredients in descending order with a combined total meets the labelling requirement. Individual amounts are not required.
Does a trademarked ingredient mean a good dose?
No. A branded ingredient inside a blend still has an undisclosed amount. The trademark speaks to the source, not the quantity.
How can I tell if an ingredient is underdosed?
Look up the dose used in research, then compare it against the blend total. If the whole blend weighs less than one studied dose, the individual ingredients cannot be at studied levels.
Sources
- U.S. Food and Drug Administration — Dietary Supplements, for labelling requirements and regulatory status.
Medical disclaimer. This article is general information, not medical advice, and cannot account for your history, medication or symptoms. Speak to a doctor or pharmacist before starting any supplement. Read our full disclaimer.