What is fairy dusting? The tiny-dose label trick in plain English

Fairy dusting is not an official FDA category. It is a very useful nickname for a familiar supplement move: put an impressive ingredient on the label, then make the actual dose hard to judge. FDA dietary supplement labeling guide

Sometimes the dose is listed and it is tiny. Sometimes the ingredient is tucked inside a proprietary blend. Sometimes the claim on the front sounds much bigger than the facts panel on the back. Either way, the ingredient is doing more marketing work than label work.

That matters because dietary supplements are not preapproved by FDA for safety and effectiveness before sale, and supplement companies are responsible for making sure their products meet the law. FDA 101 dietary supplements

Imagine a greens powder that brags about a fancy mushroom, an adaptogen, and an antioxidant blend. Nice lineup. Then you turn the tub around and find one giant blend with no individual amounts.

Now the label has made you notice the ingredients, but it has not given you enough information to know whether any one of them shows up in a meaningful amount. That is the fairy dusting problem.

FDA's labeling guide says Supplement Facts panels list dietary ingredients and amounts, and it also explains how other dietary ingredients and proprietary blends are handled. The label can be technically informative and still leave the buyer doing detective work. FDA dietary supplement labeling guide

Proprietary blends are the cozy hiding spot for fairy dusting. The label may tell you the total blend size and list ingredients in order, but the buyer still may not know the amount of each ingredient.

That does not prove the formula is weak. It proves the formula is harder to audit. There is a difference, and that difference is exactly where marketing likes to hang out.

The order clue helps a little. Ingredients earlier in the blend generally contribute more by weight than ingredients later in the blend. But order is not a dose. A parade is not a spreadsheet. FDA dietary supplement labeling guide

The slippery part is when marketing leans on research about an ingredient without showing that the product contains a comparable amount of that ingredient.

FTC guidance says health-product claims should be backed by competent and reliable scientific evidence. That does not mean a brand can point at a study, sprinkle in a mystery amount, and call it a day. FTC health products compliance guidance

If the ingredient amount is hidden, the reader cannot tell whether the product is meaningfully similar to the evidence being implied. That is not a small detail. That is the whole snack.

NutriScore does not treat every proprietary blend as a scam. That would be too easy and not quite fair.

But hidden amounts do cost trust. A formula with clear ingredient amounts is easier to score, easier to compare, and easier for a buyer to understand. A formula that hides the dose asks the reader to trust the brand's homework without seeing the math. FDA dietary supplement labeling guide

That is why fairy dusting belongs in the penalty box. Not because every hidden ingredient is useless, but because hidden dose math makes the strongest claims harder to believe.

Here is the light version: if a supplement makes you say, wow, that ingredient sounds important, the next sentence should be, cool, how much is in there?

If the answer is easy to find, great. If the answer is buried inside a blend, missing, or replaced with brand poetry, keep your wallet in its pocket for a second.

The best labels do not need magic dust. They just show the dose.