Are emulsifiers safe to eat? Experts explain

The word 'emulsifier' may sound scientific, but if you're a keen home cook, chances are you're already familiar with the concept.

Simply put, emulsifiers make it easier for several substances to combine into a single, cohesive whole.

To make mayonnaise, egg yolks – which are rich in lecithin (a natural emulsifier) – hold the sauce together. In salad dressings, mustard binds oil and vinegar.

Emulsification is a common technique in home cooking, so it seems confusing that they have been linked to poor gut health. But, that's because some emulsifiers are manufactured and used in ultra-processed foods.

Here's what the experts say.

Dr Alicia Sandall, external, a registered dietitian, explains: "Emulsifiers can have many different functions in food – for example, retaining water for freshness, strengthening dough crumb texture, reducing the melting rates of frozen foods, lengthening the shelf life of cream-based foods, and as gelling agents."

That means emulsifiers are commonly in ultra-processed foods (UPFs) like cakes, milkshakes, ice cream, chocolate, bread, margarine, nut butters (the emulsifiers prevent the oil from separating), plus pre-made frostings and ready meals.

"Research suggests that emulsifiers, especially those that are naturally derived, are safe," says Haffner.

"Although emulsifiers are used in small quantities, their abundance in packaged foods has caused many to question if they could potentially cause harm. In the UK, the FSA reviews the safety of approved food additives, external based on the best, most up-to-date research."

By UK law, manufacturers must provide information about and list any additives, external (including emulsifiers) used on the label, along with their E number, external.

Tanya Haffner, external, a registered dietitian and founder of MyNutriWeb, says: "Many emulsifiers used today are of a naturally derived variety called hydrocolloids.

"These serve as thickening agents, external and support the structure, texture, flavour, and shelf life of various food products, and they are often referred to simply as 'gums' because of the food texture and consistency they create."

Some are made from plants and aquatic sources. Locust bean gum is made from the beans of the carob (locust bean) tree and is used to extend the shelf life of confectionery. Carrageenan, made from red seaweeds, is used as a thickener for soy milk and milkshakes.

Lecithin is a natural emulsifier and is found in soybeans, egg yolks and other foods. It's often used in chocolate as a replacement for cocoa butter, and it makes chocolate easier to temper and mould.

Xanthan gum, often used as a thickener or stabiliser, is a product of microbial fermentation, external. Many gluten-free bakers and commercial bakers use xanthan gum to give elasticity and open texture to bread that gluten in wheat would otherwise provide.

Mono and diglycerides, external and sodium stearoyl lactylate are also used as 'bread improvers' and 'dough conditioners', to make production faster and easier and to extend the loaf's shelf life.

Agar, derived from algae, is a vegan gelatine alternative.

Gum arabic is used in cake decorations, frozen desserts and soft-drink syrups. Lactic acid esters are used in ice cream and imitation creams, and acetic acid esters are used in cakes and shortenings.

In a recent trial, external, common emulsifier carboxymethylcellulose was shown to significantly affect the gut bacteria in healthy adults. This and polysorbate-80 were also linked to inflammation. Some animal and human studies, external also suggest emulsifier carrageenan may subtly affect the gut barrier and inflammation, too.

That being said, there's still not enough research to suggest singular emulsifiers are the cause of bad gut health – what's more likely, based on the evidence, is that a diet heavy in UPFs (which often includes large amounts of emulsifiers, fat, sugar and salt) may negatively affect our gut health, external.

There's evidence that certain emulsifiers can have some health benefits. "It depends on the type of emulsifier and amount used," explains Haffner. "Some of the gums, external can be a source of soluble fibre and most of us can benefit from eating more fibre."

Doctor Adele Costabile, external, professor in clinical nutrition and the microbiome, says, "Soy lecithin and guar gum may lower cholesterol levels, and several studies have linked acacia and xanthan gums with improvements in insulin function among people with type 2 diabetes.

"Acacia also appears to act as a natural prebiotic, external, feeding the beneficial bacteria in the gut."

For most people without existing health problems (such as irritable bowel syndrome), there's no need to say no to the occasional ice cream.

"As yet, we cannot say that people should avoid eating emulsifiers," says professor of dietetics at King's College London, Kevin Whelan.

Even still, "most scientists, dietitians, and doctors would recommend that it's sensible to eat a diet that contains more unprocessed, natural plant foods."

Originally published November 2022. Updated February 2026.

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