Our gastro-intestinal microbiota plays a major role in our lives, from our digestive health and how well we are able to absorb nutrients, all the way up to our brain function through the gut-brain axis. So it is no surprise that our gut bacteria is heavily influenced by our diet and the foods we eat. It is well known that artificial sweeteners and ultra-processed foods have been linked to intestinal inflammation and certain forms of metabolic dysregulation (Naimi et al., 2021). However, there is another food additive present in many foods that is often overlooked by mainstream health media, and those are known as emulsifiers. Emulsifiers are a type of food additive that makes the mixing of two immiscible liquids (think water and fat), possible, for a more homogenous consistency. This is commonly found in things like peanut butter, ice cream, and salad dressings. In recent years, the effect of emulsifiers on our gut microbiome have become more widely studied, and we are learning just why we may want to start limiting our exposure to them in the foods we eat.
There are between 3,000-10,000 “food additives” that have been approved for use in the United States by the Food and Drug Administration (FDA) (Tracy, 2023). Of these 10,000 additives, only 450 have been placed on a Generally Regarded As Safe or “GRAS” list. Once items are placed on the GRAS list, there are no regulatory requirements to monitor their ongoing safety and use regardless of how their concentrations and extended usage differs from the initial study that determined its relative harmlessness. Furthermore, common umbrella terms are used for emulsifiers that have been approved, and synthetically modified variants of that emulsifier can be used without further testing on the product’s safety (Richey Levine et al., 2021).
Some of the most commonly used emulsifiers today are lecithin, mono- and diglycerides (MDG), monosodium phosphate derivatives of mono- and diglycerides, and diacetyl tartaric ester of monoglycerides (DATEM). Lecithin is the most abundant component in cell membranes and it’s what gives egg yolks their natural binding capability in baked goods. Lecithin is biochemically identified as phosphatidylcholine (PC), and regulatory requirements allow companies to label anything with PC as the main component as “lecithin”, with a variety of unspecified phospholipids in varying concentrations unchecked and unregulated (Richey Levine et al., 2021).
Synthetic emulsifier carboxymethylcellulose (CMC) is another widely used emulsifier that has been shown to have detrimental effects on the gut microbiome. In a double-blind human trial by Chassaing et al. it was shown that participants who consumed CMC during the study had increased abdominal discomfort and reduced microbiota diversity compared to the control participants. Two participants who consumed the emulsifier also exhibited early signs of leaky gut syndrome. A recent study conducted in France with over 100,000 participants showed a direct correlation between dietary emulsifier consumption and Type II diabetes (Salame et al., 2024). Additionally, high intake of the mono- and diglyceride emulsifiers has been positively associated with cardiovascular disease, coronary heart disease, and cerebrovascular disease (Daoust, 2023).
Every day companies are creating new ways to improve their products. The development of unique and different emulsifiers allows manufacturers to make their products creamier, tastier, and more shelf stable than their competitors. In return, we purchase the items that last longer to avoid losing money on the products that spoil more quickly. Unfortunately, many changes to emulsifier composition and food additives go widely unregulated. Where the United States has over 10,000 approved food additives, the European Union has just over 300. It begs the question: is our government more concerned with the longevity of the consumers, or the longevity of the products we eat?
References
Chassaing, B., Compher, C., Bonhomme, B., Liu, Q., Tian, Y., Walters, W., Nessel, L., Delaroque, C., Hao, F., Gershuni, V., Chau, L., Ni, J., Bewtra, M., Albenberg, L., Bretin, A., McKeever, L., Ley, R. E., Patterson, A. D., Wu, G. D., & Gewirtz, A. T. (2021). Randomized controlled-feeding study of dietary emulsifier carboxymethylcellulose reveals detrimental impacts on the gut microbiota and metabolome. Gastroenterology, 162(3). https://doi.org/10.1053/j.gastro.2021.11.006
Daoust, L. (2023). Food additive emulsifiers and cardiovascular disease. Nature Food, 4(10), 831–831. https://doi.org/10.1038/s43016-023-00865-z
Naimi, S., Viennois, E., Gewirtz, A. T., & Chassaing, B. (2021). Direct impact of commonly used dietary emulsifiers on human gut microbiota. Microbiome, 9(1). https://doi.org/10.1186/s40168-020-00996-6
Richey Levine, A., Picoraro, J. A., Dorfzaun, S., & LeLeiko, N. S. (2021). Emulsifiers and Intestinal Health: An Introduction. Journal of Pediatric Gastroenterology & Nutrition, 74(3), 314–319. https://doi.org/10.1097/mpg.0000000000003361
Salame, C., Javaux, G., Laury Sellem, Viennois, E., Fabien, Cédric Agaësse, Alexandre De Sa, Huybrechts, I., Pierre, F., Coumoul, X., Julia, C., Emmanuelle Kesse-Guyot, Allès, B., Fezeu, L. K., Serge Hercberg, Mélanie Deschasaux-Tanguy, Cosson, E., Sopio Tatulashvili, Benoit Chassaing, & Srour, B. (2024). Food additive emulsifiers and the risk of type 2 diabetes: analysis of data from the NutriNet-Santé prospective cohort study. the Lancet. Diabetes & Endocrinology, 12(5), 339–349. https://doi.org/10.1016/s2213-8587(24)00086-x
Shakil, M. H., Trisha, A. T., Rahman, M., Talukdar, S., Kobun, R., Huda, N., & Zzaman, W. (2022). Nitrites in Cured Meats, Health Risk Issues, Alternatives to Nitrites: a Review. Foods, 11(21), 3355. https://doi.org/10.3390/foods11213355
Tracy, B. (2023, February 21). FDA hasn’t Reviewed Some Food Additives in Decades. Www.cbsnews.com. https://www.cbsnews.com/news/fda-food-additives-safety-review-california-legislation/ Assessed and Endorsed by the MedReport Medical Review Board