Invisible Threat: Everyday Additives That Compromise Our Microbiota and Immune Defenses

For several years, the composition of our processed foods has prompted increasing vigilance. Behind creamy textures, the shelf life of products and more homogeneous preparations, hides a multitude of additives with well-defined functions. Among them, food emulsifiers occupy a central place. Their widespread use, including in products intended for infants, now raises profound questions about their long-term effects on immune and intestinal health.

Massive exposure from a very young age

Food emulsifiers allow you to mix substances that do not mix naturally, such as oil and water. They are essential to the texture and stability of many products: ready meals, industrial pastries, ice creams, margarines, thickened sauces and even certain infant formulas. According to EUFIC, Europe authorizes more than 60 additives of this type, including mono and diglycerides of fatty acids E471, lecithin E322 or carrageenan E407.

This omnipresence leads to massive exposure. In the PLOS medicine study, 99.8% of participants consumed at least one food emulsifier. However, certain animal experiments had already warned of their effects: modification of the composition of the intestinal microbiota, stimulation of inflammation, weakening of the intestinal barrier. Warning signals that human research is beginning to confirm.

An association between food emulsifiers and cancer

Relayed by the SciTechDaily site, a recent study by the Pasteur Institute highlighted the long-term effects of exposure to emulsifiers in mice. Researchers have shown that when mothers consume certain emulsifiers, such as carboxymethylcellulose and polysorbate 80, before and during pregnancy, their babies develop microbiota disruptions, chronic inflammation and an increased risk of obesity, without having been directly exposed. According to them, the early closure of intestinal immune passages, called GAPs, plays a key role in this silent transmission.

This work, published in Nature Communications in November 2025, highlights the importance of the maternal nutritional environment in building the child's immune system. They ask many questions about the regulations governing the presence of additives in foods intended for infants or pregnant women.

Epidemiological confirmation in humans

To find out if these effects observed in animals also exist in humans, researchers analyzed data from 92,000 adults. Their study reveals an association between high consumption of certain emulsifiers and an increased risk of breast and prostate cancers. They notably highlighted a link with mono- and diglycerides of fatty acids (E471), as well as with carrageenans (E407).

Although no relationship has been observed with colorectal cancer, these data reinforce the concerns already raised by experimental work. They remind us of the difficulty in assessing the cumulative impact of small daily doses of additives, particularly in the youngest individuals.