Introduction
If you’re looking into healthier food alternatives, understanding what goes into ultra-processed foods is crucial. Food additives, especially emulsifiers, have become a hot topic among health-conscious consumers. These ingredients give ice cream its creamy consistency or keep oil and vinegar from separating in salad dressing, but recent studies say they may impact our health in unexpected ways. In this post, we’ll explore what food emulsifiers are, why they’re used, and what recent scientific research suggests about their impact on well-being. The goal is to provide insights that help you make more informed and health-aligned food choices.
What Are Emulsifiers?
Emulsifiers are substances that help mix ingredients that normally don’t blend well, like oil and water. At the molecular level, emulsifiers have both water-friendly and fat-friendly sides, allowing them to stabilize mixtures of fats and liquids. This makes them incredibly useful in food manufacturing – they create smooth textures, improve appearance, and extend shelf life in products ranging from baked goods to sauces. In fact, emulsifiers are among the most commonly used food additives in ultra-processed foods, added specifically to improve texture and stability.
You can find emulsifiers in thousands of everyday foods: they’re in chocolate and peanut butter (to keep oils from separating), in ice cream (for that soft, uniform mouthfeel), in creamy dressings and mayonnaise, and in many packaged snacks. Common examples include lecithin (often derived from soy or egg yolk), mono- and diglycerides (found in many breads and desserts), carrageenan (a thickener from seaweed used in dairy alternatives and jellies), various gums like xanthan or guar gum, and compounds like polysorbate 80 or carboxymethylcellulose. One analysis found that 7 of the 10 most widely consumed additives in a French adult population were emulsifiers. There are dozens of emulsifiers approved for use (around 60 in Europe and even more in the US), each tested for safety in isolation. However, studies suggest that safety in small doses or short-term may not tell the whole story when these additives are eaten regularly over a lifetime. This is why scientists have begun re-examining emulsifiers, especially for their subtle effects on the gut.
What Does the Research Say?
Emulsifiers, Gut Health, and Metabolism
Over the past decade, researchers have uncovered evidence that emulsifiers might disturb the gut’s delicate balance. Much of this work has been in animal studies or controlled lab experiments. For example, one recent mouse study found that certain emulsifiers – specifically sucrose fatty acid esters and carboxymethylcellulose (CMC) – induced high blood sugar levels and insulin resistance in mice. In that study, all tested emulsifiers (including lecithin, CMC, sucrose esters, and mono- and diglycerides) also disrupted the normal diversity of gut microbiota, essentially causing a state of dysbiosis (microbial imbalance) in the intestines. Notably, the mice consuming emulsifiers showed signs of metabolic disturbances, and one emulsifier (the mono- and diglyceride blend) even caused gut bacteria to encroach into the mucus layer that normally protects the intestinal lining. This bacterial encroachment was accompanied by elevated inflammatory molecules, hinting at a potential mechanism by which emulsifiers could provoke inflammation. In simple terms, the additives appeared to make the mice’s metabolism worse and their gut barriers weaker – a combination that could set the stage for obesity, diabetes, or other metabolic issues.
A key suspect is how emulsifiers interact with gut bacteria. Our intestines are home to trillions of microbes that play crucial roles in digestion, immunity, and overall health. Scientists have observed that emulsifiers can alter the composition and behavior of these microbes. A comprehensive 2021 study tested 20 common dietary emulsifiers on an ex vivo human gut microbiome. The results were striking: several widely used emulsifiers directly changed the gut microbiota in ways that are considered pro-inflammatory. In accordance with earlier animal research, both CMC and polysorbate 80 had lasting, detrimental impacts on the microbiota’s composition and function. Many of the other emulsifiers tested (including certain gums and carrageenan) also disturbed the microbial balance. However, a few emulsifiers showed little to no effect on the gut microbes. Notably, lecithin did not significantly disrupt the microbiome in this model. Since lecithin is frequently derived from soy—a plant-based ingredient valued for its nutritional profile—this finding is particularly relevant for health-conscious consumers. Soy-derived lecithin’s minimal impact on the microbiome in this study suggests it could be a more favorable emulsifier option for those looking to support gut health. This supports the broader idea that not all emulsifiers are equal in their biological effects—some may be relatively neutral or even compatible with a health-forward diet, while others appear to be more disruptive.
Laboratory studies have also shed light on how emulsifiers could be contributing to diseases associated with chronic gut inflammation. Research in cell cultures and rodents suggests that emulsifiers like polysorbate 80 can make the intestinal wall more permeable. At very low concentrations, polysorbate 80 has been shown to trigger bacterial migration across gut tissue and to induce intestinal inflammation in experimental models. These changes resemble the kind of gut barrier breakdown observed in conditions such as inflammatory bowel disease. Scientists suggest that if certain emulsifiers chronically weaken the mucus barrier or alter the microbiota, they might ultimately provoke immune reactions or metabolic changes that increase the risk of diseases beyond the gut. Some researchers note that certain naturally derived emulsifiers might interact differently with our biology.
Emulsifiers and Human Health: Epidemiological Evidence
While animal and lab studies provide clues, what about real-world human diets? Direct experiments in people are challenging, but scientists have turned to observational studies for insight. Two large prospective cohort studies in France – part of the ongoing NutriNet-Santé project – have recently examined links between emulsifier intake and health outcomes in adults.
One of these studies investigated emulsifier intake in relation to cancer risk. The researchers collected data from over 100,000 adults and focused on emulsifiers commonly found in processed foods. After about 7 years of follow-up, the study reported a pattern: people who ate the most of certain emulsifiers had higher rates of overall cancer, particularly breast cancer in women and prostate cancer in men. For instance, higher consumption of carrageenans and of monoglyceride emulsifiers was associated with an increase in the risk of these cancers compared to those with the lowest intake. The authors cautioned that these results need to be confirmed in other populations. Although the researchers adjusted for many dietary and lifestyle variables, it’s important to note that emulsifiers are typically found in ultra-processed foods, which contain a variety of other additives and ingredients. Therefore, the health effects observed may not be solely due to emulsifiers, but could reflect the broader dietary patterns associated with ultra-processed food consumption.
Another large analysis from the NutriNet-Santé cohort looked at emulsifier intake and cardiovascular disease (CVD). This study followed around 95,000 adults with no prior CVD for a median of 7.4 years, tracking who had heart attacks, strokes, or other cardiovascular events. The findings indicated that higher total intake of emulsifiers was associated with a small but significant increase in the risk of cardiovascular disease over time. In particular, five types of emulsifiers and two broad categories were identified as contributors. One category was the cellulose family. People who consumed more of these cellulose-based emulsifiers had a higher incidence of CVD and specifically coronary heart disease. Another group flagged was the monoglyceride and diglyceride emulsifiers. Higher intakes of these were linked to increased risks of both overall CVD and cerebrovascular events. These types of studies show associations, not causation, but they add to a growing body of evidence that emulsifier consumption could be a factor in chronic disease development.
Takeaways for Consumers Seeking Healthier Food Alternatives
- Emulsifiers are common in modern food. They make ultra-processed foods more palatable by improving texture and shelf stability.
- Studies say some emulsifiers may disrupt gut health. Lab studies have found that certain emulsifiers can disturb the gut microbiome and erode the protective mucus lining of the intestines.
- High intake of emulsifiers has been linked to health risks in population studies. Large-scale French studies have observed that people who consume more emulsifiers tend to have higher rates of cardiovascular disease and certain cancers.
- Not all emulsifiers are created equal. Lecithin, for example, has shown minimal effect on the microbiome in lab studies. Others like polysorbate 80 or carboxymethylcellulose are more consistently associated with negative outcomes.
- Moderation and whole foods are key. Emphasizing whole foods naturally limits emulsifier exposure. Reading ingredient labels can help identify highly processed items. Look for simple ingredient lists when shopping for healthier food alternatives.
- Stay informed. Science on emulsifiers is evolving. Monitoring ongoing research allows for more informed decisions about healthier food options.
Conclusion
Emulsifiers play a behind-the-scenes role in making our foods tasty and shelf-stable, but studies say they may not be biologically inert ingredients. Research linking these additives to gut microbial changes, inflammation, and disease risk is prompting scientists to take a closer look. There is no need for panic, but a precautionary approach – minimizing intake of ultra-processed foods and favoring whole ingredients – aligns with current science. Choosing simpler foods when possible is a practical way to eat both happily and healthfully while exploring healthier food alternatives.
References
Partridge, Dominic, et al. “Food Additives: Assessing the Impact of Exposure to Permitted Emulsifiers on Bowel and Metabolic Health – Introducing the FADiets Study.” Nutrition Bulletin 44, no. 4 (2019): 329–349. https://doi.org/10.1111/nbu.12400.
Sellem, Laury, et al. “Food Additive Emulsifiers and Cancer Risk: Results from the French Prospective NutriNet-Santé Cohort.” PLOS Medicine 20, no. 7 (2023): e1004338. https://doi.org/10.1371/journal.pmed.1004338.
Sellem, Laury, et al. “Food Additive Emulsifiers and Risk of Cardiovascular Disease in the NutriNet-Santé Cohort: Prospective Cohort Study.” BMJ 382 (2023): e076058. https://doi.org/10.1136/bmj-2023-076058.
Viennois, Emilie, et al. “Direct Impact of Commonly Used Dietary Emulsifiers on Human Gut Microbiota.” Microbiome 9, no. 1 (2021): 66. https://doi.org/10.1186/s40168-020-00996-6.
Wu, Wei-Kai, et al. “Common Dietary Emulsifiers Promote Metabolic Disorders and Intestinal Microbiota Dysbiosis in Mice.” Communications Biology 7, no. 1 (2024): 749. https://doi.org/10.1038/s42003-024-06224-3.