From ice cream to ketchup: These food additives could be secretly damaging your gut |

For decades, food additives have been considered harmless ingredients that make our foods smoother, creamier, and longer-lasting. But recent studies, including one published in Frontiers in Nutrition, have raised new concerns, suggesting that some of these supposedly “safe” additives may quietly disrupt the gut’s delicate microbial balance, with possible effects on immunity, metabolism, and long-term health.Emulsifiers, the compounds that help blend ingredients like oil and water, are found in countless ultra-processed foods, from ice cream and salad dressings to bread and chocolate. They prevent separation, improve texture, and extend shelf life. Yet emerging evidence, including research in the BMJ and Clinical Gastroenterology and Hepatology, now indicates that certain emulsifiers might interfere with how the gut’s microbial community functions.

The gut microbiome, a vast community of trillions of microbes, plays a crucial role in digestion, metabolism, and immune defence. Disruptions to this ecosystem are increasingly linked to chronic health conditions. Research has shown that some commonly used emulsifiers, including carboxymethyl cellulose, polysorbate-80, and carrageenan, can alter the balance of gut bacteria in ways that may reduce beneficial compounds called short-chain fatty acids, which support gut and immune health.

A Nature Reviews Gastroenterology & Hepatology study noted that these additives may diminish microbial diversity, while a Cell Reports (2021) study demonstrated that carboxymethyl cellulose could damage the intestinal mucus barrier, potentially leading to inflammation. These findings suggest that even seemingly minor alterations in gut microbes may have cascading effects on health.Furthermore, human trials have observed that some emulsifiers make the intestinal lining slightly “leakier,” allowing unwanted molecules to pass through and possibly trigger inflammation. While scientists stress that these effects are still under investigation, the consistency of such findings underscores the need for a closer look at how everyday processed foods affect gut integrity.

What the research really says

Several large-scale studies have now examined the potential long-term impact of emulsifier consumption on chronic disease risk. The BMJ (2023) cohort study involving nearly 95,000 adults in France found that individuals with higher intake of additives like E471 and E472 had a modestly increased risk of heart disease and type 2 diabetes. Another analysis in Public Health Nutrition (2023) revealed that although these emulsifiers are used in a relatively small proportion of supermarket products, their widespread presence in processed foods can lead to cumulative exposure.The ADDapt Trial (King’s College London) provided further insight by showing that people with Crohn’s disease who followed a low-emulsifier diet experienced improved gut health and reduced symptoms compared to those who did not. Together, these studies point to a pattern: while the short-term effects of additives may seem minimal, their continuous intake could influence gut microbiota and disease susceptibility over time.

Even so, researchers emphasise that current data reflect associations, not causation. Most additives are approved as safe based on animal studies at extremely high doses. The real question now is whether years of low-dose, repeated exposure in humans can subtly reshape the gut microbiome in ways that affect long-term health.

So, should you be worried?

The takeaway is not that all emulsifiers are harmful, but that context matters. A diet dominated by ultra-processed foods, high in additives but low in fibre, creates an environment where the gut microbiome struggles to thrive. This imbalance may increase inflammation, weaken metabolism, and heighten disease risk over time.Experts suggest focusing on what to add rather than what to remove. Incorporating whole, plant-based foods such as fruits, vegetables, legumes, and wholegrains naturally supports a diverse microbiome, providing the dietary fibre that beneficial gut bacteria rely on. Over time, this can help counteract any negative effects of processed food additives.An occasional ice cream or bottle of ketchup will not undo your health. However, evidence increasingly shows that long-term gut harmony depends on eating patterns, not individual ingredients. For most people, the simplest and most effective approach remains: less processing, more plants.