Ingredient
Kaolin
The same white powder is regulated three separate ways depending on whether you spread it, swallow it, or never meant to eat it at all.
- INCI name
- Kaolin
- Also on labels as
- China clay, Kaolinite, Clay
- Found in
- cosmetics, food
Part of Eczema and atopic skin · Medicines
Most ingredients on this site are regulated once. Kaolin is regulated three times, by three different parts of the same title, and the three do not refer to each other.
As something you spread
The skin protectant monograph permits “Kaolin, 4 to 20 percent”, which puts it on the same list as Petrolatum, Glycerin and Calamine. A product using it at that strength and claiming to protect skin is a drug and prints a Drug Facts panel; the identical clay in a face mask making no such claim prints nothing.
As something you swallow
The antidiarrhoeal monograph is one of the shortest active-ingredient lists in the whole of the over-the-counter system. It reads, in full, that the active ingredient “consists of any one of the following when used within the dosage limits established for each ingredient in § 335.50(d)”, and then names two: bismuth subsalicylate, and kaolin.
That is the entire permitted field. And the claim a kaolin product is allowed to make is prescribed word for word, in a form that is unusually specific about time: “helps firm stool within 24 to 48 hours”.
As something nobody meant to eat
The food regulation does not treat kaolin as an ingredient at all in the ordinary sense. It affirms it as generally recognised as safe on the basis that “the ingredient is used as an indirect human food ingredient with no limitation other than current good manufacturing practice”.
Indirect means it reaches food from something food touches rather than from a recipe. The same section is where the composition is actually described: “Clay (kaolin) is a white to yellowish or grayish fine powder”, and it notes there are “at least three different minerals, kaolinite, dickite, and nacrite, classified as kaolin”.
Why the three lives matter to a label reader
They are the clearest available demonstration that a US ingredient’s rules are attached to the product’s stated purpose, not to the molecule. Nothing about the clay changes between a mask, a bottle of antidiarrhoeal suspension and a paper coating. What changes is what the package claims, and the claim selects the regulation.
That principle is the spine of the guide on which claims are regulated, and kaolin is its cleanest example.
One thing the three regulations share is silence about each other. The clay affirmed for indirect food use is not thereby approved as a food ingredient, and the antidiarrhoeal dose is not a licence to eat a cosmetic. Reading across between them is the mistake the structure invites and none of the three supports.
Sources
- 21 CFR 347.10: Skin protectant active ingredients US Food and Drug Administration, via eCFR · ecfr.gov Permits kaolin at 4 to 20 percent as a skin protectant active ingredient.
- 21 CFR 335.10: Antidiarrheal active ingredients US Food and Drug Administration, via eCFR · ecfr.gov Names kaolin and bismuth subsalicylate as the only two permitted antidiarrhoeal actives.
- 21 CFR 335.50: Labeling of antidiarrheal drug products US Food and Drug Administration, via eCFR · ecfr.gov Prescribes the wording a kaolin antidiarrhoeal product uses to state what it does.
- 21 CFR 186.1256: Clay (kaolin) US Food and Drug Administration, via eCFR · ecfr.gov Affirms clay (kaolin) as GRAS as an indirect human food ingredient and describes its composition.