Polysorbate 40
Synthetic emulsifier; microbiome studies debated.
- Category
- Emulsifiers
- Acceptable daily intake
- 25 mg/kg body weight/day (EFSA)
- Vegan
- maybe
- Vegetarian
- maybe
- From palm oil
- maybe
What it is
Polysorbate 40 (E434) is a highly effective, synthetic emulsifier. It forces oil and water to mix smoothly, preventing separation in processed foods.
How it is used in food
A mid-chain polysorbate emulsifier.
Commonly found in- Ice cream (prevents ice crystals and makes it melt smoothly)
- Salad dressings
- Chewing gum
Health and safety
Shares the family’s microbiome debate.
Polysorbates are currently under intense scrutiny from the scientific community. While EFSA approved a group ADI of 25 mg/kg bw/day in 2015 based on traditional toxicology, newer microbiome research has raised alarms.
Microbiome disruption and inflammation
In mice, polysorbate 80 eroded the gut mucosal barrier, allowing bacteria closer to the intestinal wall and promoting low-grade inflammation and metabolic syndrome. The effect is assumed to extend across the polysorbate group, but it has been demonstrated for P80.
Opened by the 2015 Nature mouse study.
Regulatory status
| Region | Status | Notes |
|---|---|---|
| Australia & New Zealand FSANZ |
Permitted | Permitted. |
| European Union EFSA / European Commission |
Permitted | Authorised for food use under EU regulations (Annex II). |
| United States FDA (Food and Drug Administration) |
Not approved | Not permitted in US food. Polysorbate 40 appears in 21 CFR only in the food-contact parts (175, 178) and is absent from FDA's Substances Added to Food inventory; the direct food additive listings cover polysorbates 60, 65 and 80 (172.836/.838/.840). |
Identification on labels
- E-number
- E434
Alternatives to this additive
- E322: Lecithins — A plant- or egg-derived emulsifier, and the one least implicated in the gut-barrier research on synthetic emulsifiers.
How it is made
Produced by reacting sorbitol and a specific fatty acid with ethylene oxide (a petrochemical gas) to make it water-soluble.
- Ethoxylation — Ethylene oxide gas is reacted with a sorbitan ester to form the final polysorbate.
Worth knowing
Chemically similar to Polysorbate 80.
Conclusion
The concern comes from Chassaing et al. (Nature, 2015), where polysorbate 80 stripped the protective mucus layer from the gut lining in mice, letting bacteria reach the intestinal wall and driving low-grade inflammation linked to metabolic syndrome and IBD. That work tested P80, not this polysorbate — the group is assumed to behave alike, which is an assumption rather than a finding. Human feeding trials on emulsifiers are underway and so far point the same way. EFSA's 25 mg/kg group ADI predates this literature.
References
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Open the appEntry last reviewed 2026-07-28.
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