E525
Potassium hydroxide
What the research shows
Not enough
published research on this page yet
A white solid also called caustic potash.
It is used to make soft and liquid soaps.1
- Vegan
- Vegetarian
- EU permitted
What research says
Single cases of misuse or overdose
One person or one incident, such as an accidental overdose or a mistake in a kitchen or factory. They are real, but a single case does not show what happens at normal amounts, so the signal does not count them.
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Harm from a supplement2
A person was poisoned after eating potassium hydroxide used as a nutrient in a supplement.
The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.
What expert reviews concluded
Expert panels that weigh all the research. Shown for context: the signal at the top does not count them.
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UN and WHO food additive experts (JECFA), 1965
No daily limit needed (“ADI not specified”, JECFA’s term for very low toxicity).
Regulatory status
Checked Sep 2026-
United States Permitted FDA 21 CFR 184.1631
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European Union Permitted EUR-Lex Reg. (EC) 1333/2008
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United Kingdom Permitted FSA retained EU law
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Canada Permitted Health Canada · Adjusting Agents
Status reflects the named register on the date checked. It is not a safety rating.
How we checkProducts
The 6 most-scanned of 530 products on Open Food Facts that list potassium hydroxide.
- Fine Dark Cocoa Powder Dr. Oetker · 190 g 2 additives
- Cocoa Dr. Oetker · 100 g 2 additives
- Original nutrition shake Ensure · 237 ml 5 additives
- Alkaline Ionized Hydration Member's Mark 0 additives
- Cacao Dr. Oetker · 50 grame 2 additives
- Cocoa Asda · 250 g 2 additives
References
- 1Potassium hydroxide. Wikipedia. Accessed September 26, 2026. CC BY-SA 4.0.
- 2Zovi A, Ferrara F. Is Potassium Hydroxide Safe as a Source of Nutrient in Food Supplements? An Expert Opinion. Int J Vitam Nutr Res. 2025;95(2):31370. doi:10.31083/IJVNR31370