E504 · Magnesium carbonate, magnesium hydroxide carbonate
- WHO
- Safe
- FDA
- Safe
- EFSA
- Safe
- FSANZ
- Safe
- Japan
- Safe
- UK FSA
- Safe
- Health Canada
- Safe
What is E504?
Magnesium carbonate and magnesium hydroxide carbonate are used in food as anti-caking agents, acidity regulators, and colour retention agents, commonly found in powdered foods, spice blends, and some confectionery. They are also used outside food as antacids and in industrial products like rubber and fireproofing materials, but the food-grade forms are considered safe at typical use levels.
Also appears on labels as: Magnesium carbonate, Magnesium hydroxide carbonate, Basic magnesium carbonate, Magnesium hydrogen carbonate, Magnesium bicarbonate, Magnesium carbonate hydroxide, Magnesium carbonate hydrate, Heavy magnesium carbonate, Light magnesium carbonate, Magnesium salts of carbonic acid, MgCO3, Mg(HCO3)2.
What the evidence says
- Very high intake can have a mild laxative effect, similar to other magnesium salts.
- Generally recognized as safe at typical food levels.
Research behind the verdict
- Magnesium Carbonate and Hydroxide Carbonate: Safety Assessment for Organic Food Processing — USDA National Organic Standards Board, USDA Agricultural Marketing Service (2024). A comprehensive 2024 evaluation of magnesium carbonate (E504) conducted as part of the USDA National Organic Standards Board review for inclusion in organic food processing. The study examined both magnesium carbonate and magnesium hydroxide carbonate forms as processing aids. The research confirmed their safety for use in food applications, noting their effectiveness as anti-caking agents and processing aids. The assessment found no significant health concerns and supported their inclusion in approved food processing applications.[safe]
Frequently asked questions
Is E504 safe?
Our overall verdict for E504 (Magnesium carbonate, magnesium hydroxide carbonate) is “Safe”, based on the most cautious of the major regulators’ positions — FDA: safe; WHO: safe; EFSA: safe; FSANZ: safe; Japan: safe; UK FSA: safe; Health Canada: safe.
Is E504 vegan, halal or gluten-free?
According to our ingredient data for Magnesium carbonate, magnesium hydroxide carbonate — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E504 and why is it used?
Magnesium carbonate and magnesium hydroxide carbonate are used in food as anti-caking agents, acidity regulators, and colour retention agents, commonly found in powdered foods, spice blends, and some confectionery. They are also used outside food as antacids and in industrial products like rubber and fireproofing materials, but the food-grade forms are considered safe at typical use levels.
Does E504 contain allergens?
No known allergens are recorded for Magnesium carbonate, magnesium hydroxide carbonate.
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This page summarises publicly available regulatory assessments and research. It is general information, not medical advice. Sources: EFSA, FDA, WHO and the studies linked above.