Mono- and diglycerides
Fat-derived emulsifiers that stop oil and water separating, used widely in bread, spreads, ice cream and margarine.
E471 can contain trans fatty acids and glycidyl esters as manufacturing impurities. Glycidyl esters break down to glycidol in the body, which IARC classifies as probably carcinogenic (Group 2A). Regulators have called for tighter limits on both impurities in the product specifications.
What is it?
Mono- and diglycerides are partial glycerol esters of fatty acids, produced commercially by reacting glycerol with natural or hydrogenated vegetable or animal fats. They occur naturally in small amounts in digested fat in the gut. As additives they are not pure compounds but a mixture, with the mono- and diglyceride content varying by grade.
What does it do?
They are emulsifiers: the glycerol head is water-attracting and the fatty acid tail is oil-attracting, so they sit at oil-water interfaces and prevent the two phases from separating. In bread they interact with starch to slow staling; in ice cream they improve texture and resistance to melting; in margarine and spreads they stabilise the water-in-fat emulsion.
Where you will see it
Sliced bread and other baked goods, margarine, low-fat spreads, ice cream, whipped cream, chocolate, coffee whiteners, peanut butter, instant mashed potato, cake mixes and cooking oils. On a UK label it appears as 'mono- and diglycerides of fatty acids', 'mono- and diacylglycerols' or 'E471'.
What the science says
Trans fatty acids in the manufacturing process
When vegetable oils are partially hydrogenated or deodorised to make E471, trans fatty acids can form as a byproduct. Trans fats raise LDL (bad) cholesterol and lower HDL (good) cholesterol, increasing cardiovascular risk. The EFSA re-evaluation in 2017 found no maximum limit for trans fatty acids in the E471 product specification and recommended one be set. In general-population-grade E471 samples tested, trans fat content reached as high as 59.92%, though the contribution to overall dietary trans fat intake depends on the amounts used in food.
No maximum limit for trans fatty acids currently exists in the EU or UK specifications for E471; EFSA recommended establishing one after finding trans fat levels up to 59.92% in commercially tested samples.
Dietary trans fatty acids raise LDL cholesterol and lower HDL cholesterol, increasing the risk of cardiovascular disease; this is an established finding across multiple meta-analyses.
Glycidyl esters and the IARC Group 2A concern
Refined vegetable oils used in E471 manufacturing can contain glycidyl esters as process contaminants. Once ingested, glycidyl esters hydrolyse to glycidol, which IARC classified as probably carcinogenic to humans (Group 2A) based on animal evidence. EFSA found no limit for glycidyl esters in E471 specifications and recommended adding one. Commercial samples had glycidyl ester levels up to 111 mg/kg, roughly ten times above the technically achievable limit proposed by regulators.
Glycidol is classified as probably carcinogenic to humans (IARC Group 2A), based on sufficient evidence in animals.
Commercial E471 samples showed glycidyl ester levels up to 111 mg/kg; EFSA recommended adding a maximum limit of 10 mg/kg to product specifications.
For infant formula-grade E471 samples, glycidyl ester levels also reached up to 111 mg/kg; the 2021 EFSA follow-up opinion recommended the same 10 mg/kg limit be applied urgently for infant products.
No numerical ADI: what that means
EFSA concluded in 2017 that no numerical acceptable daily intake (ADI) is needed, because the additive is metabolised the same way as naturally occurring dietary fat. This is a standard conclusion for substances that are physiologically normal food components at the doses used. It means the panel did not identify a tolerable upper intake from the additive itself, not that no upper limit on trans fats or impurities matters.
The EFSA ANS Panel set no numerical ADI for E471, concluding it is metabolised as ordinary dietary fat and presents no safety concern at authorised use levels, with the caveats about impurity specifications noted separately.
Use in infant formula
E471 is permitted in infant formula as a functional emulsifier. EFSA evaluated its use in formula for babies under 16 weeks separately in 2021 and found no adverse effects in available animal studies or post-market data, noting that the exposure from formula is in the same order of magnitude as mono- and diglycerides naturally present in breast milk. The main recommendation was again tightening impurity specifications, particularly for glycidyl esters.
EFSA found no safety concern for E471 in infant formula for babies under 16 weeks at authorised use levels, but flagged glycidyl ester impurity levels as the priority specification gap requiring urgent revision.
Where it stands with the regulators
Who should be careful
People avoiding animal products should check source: E471 can be derived from animal fat (including lard or tallow) as well as vegetable oils. Manufacturers are not required to specify the source on the label, so the label term 'E471' or 'mono- and diglycerides of fatty acids' alone does not confirm plant origin. Those reducing trans fat intake should note that hydrogenated-oil-derived E471 may contribute dietary trans fats; choosing products labelled 'no hydrogenated fat' reduces this exposure.
The honest read
E471 is one of the most widely used emulsifiers in the food supply and its direct physiological action is essentially that of digested fat. The honest complexity lies in its impurities: the manufacturing process can introduce trans fatty acids and glycidyl esters at levels that regulators have flagged as needing tighter control, and glycidol (the breakdown product of glycidyl esters) carries an IARC Group 2A carcinogenicity classification. Whether typical dietary exposure from E471-containing foods translates into meaningful cancer or cardiovascular risk for an individual has not been quantified in long-term human studies. The picture is not alarming for the additive in its clean form; it is more open for the real-world product with its current permissive impurity limits. Regulators have been calling for tighter specifications since 2017; whether those changes have been fully implemented in UK law is worth checking against the most recent FSA update.
Related additives
Common questions
Is E471 banned in the UK?
No. E471 is permitted in the UK under the FSA approved-additives list and assimilated EU Regulation 1333/2008. The UK FSA assessed an extension of use in 2023 and found it of low toxicological concern at the levels proposed.
Does E471 contain trans fats?
It can. When E471 is made from partially hydrogenated vegetable oils, trans fatty acids can be present as a manufacturing byproduct. EFSA found no upper limit on trans fats in E471 product specifications as of its 2017 re-evaluation, and samples tested showed up to 59.92% trans fat content. Regulators recommended setting a maximum limit; whether that limit has since been written into UK law requires checking the current FSA specification.
What foods contain E471?
It is extremely common: sliced bread and other baked goods, margarine and low-fat spreads, ice cream, chocolate, peanut butter, cooking oils, instant mashed potato, coffee whiteners, cake mixes and infant formula all commonly contain it. On UK packaging it will be listed as 'E471', 'mono- and diglycerides of fatty acids', or 'mono- and diacylglycerols'.
Is E471 vegan?
Not necessarily. E471 can be derived from either vegetable oils or animal fats such as lard or tallow. UK labelling law does not require the source to be declared, so the label 'E471' alone gives no information. Some manufacturers state 'vegetable-derived' or list the oil source; absent that, the source is unknown from the label alone.
Sources
- EFSA ANS Panel: Re-evaluation of mono- and di-glycerides of fatty acids (E 471) as food additives (2017)
- EFSA ANS Panel: Follow-up opinion on E471 in infant formula for infants below 16 weeks (2021)
- UK FSA: Outcome of assessment of the extension of use of E471 (RP1057, 2023)
- UK FSA: Approved additives and E numbers
- IARC Monographs Vol. 77: Some Industrial Chemicals -- glycidol classified Group 2A
- PMC full text: EFSA 2017 E471 re-evaluation (PMC7010209) -- cites IARC 2000 for glycidol Group 2A
- PMC full text: EFSA 2021 E471 infant formula follow-up (PMC8573540)
Aaron Keen is the founder of NutraSafe. He researches and writes every additive entry himself, from the primary sources. About the research →
This is a guide, not medical advice. If an additive affects you, speak to your GP or a dietitian.
See this on every food you scan
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
Get NutraSafe on the App Store