Calcium hydroxide (E526)
- Food Fine
- Cosmetics Caution
What is Calcium hydroxide (E526)?
Calcium hydroxide (E526), also called slaked lime, is used to adjust acidity and to make corn tortillas. Acids in the food neutralise it, so it isn't a concern in properly made food. It's fine; only the concentrated powder irritates on contact.
What does Calcium hydroxide do in cosmetics?
In cosmetics, calcium hydroxide raises pH, especially in hair removal creams and hair straighteners. Gentle, well-made products are acceptable, but strongly alkaline ones can irritate skin and seriously injure the eyes. Keep it away from your eyes and follow the directions carefully.
What is Yasno’s verdict on Calcium hydroxide?
Yasno’s verdict on Calcium hydroxide: In food: Fine. No meaningful concern at normal amounts. In cosmetics: Caution. Some evidence of a concern, it depends on the amount, or it is genuinely worth knowing. A Caution always has a specific, sourced reason.
Is Calcium hydroxide allowed in the EU?
EU status of Calcium hydroxide: In food: Permitted as a food additive. In cosmetics: Restricted in cosmetics (limits and conditions apply). Conditions and limits come from the regulation cited below. Yasno summarises them and does not replace the legal text.
| Where | EU | US |
|---|---|---|
| Food | Permitted as a food additive | Generally Recognised as Safe (GRAS, a US regulatory category) |
| Cosmetics | Restricted in cosmetics (limits and conditions apply) | Not recorded |
What else is it called?
- Slaked lime
- Hydrated lime
- Lime hydrate
Sources
- EU Food Additives Register — POL-FAD-IMPORT-3223, European Commission (DG SANTE), 2011
- Calcium hydroxide, Joint FAO/WHO Expert Committee on Food Additives (JECFA), 1965
- SCOGS Report Number 72, U.S. Food and Drug Administration, 1975
- International Chemical Safety Card: Calcium hydroxide, International Programme on Chemical Safety, 2000
- 2021 Cosmetic Ingredient Review assessment of calcium hydroxide, Cosmetic Ingredient Review, 2021
- Biocidal Products Committee assessment of calcium hydroxide/hydrated lime, European Chemicals Agency, 2021
Always check the physical label. Yasno describes evidence and regulatory status. It never says a product is free of an allergen or safe for you, and it is not medical advice.
Yasno reads the whole label from a photo and explains every ingredient like this. It is coming soon to the App Store.