Dietary emulsifiers are a common ingredient in highly processed foods that form a large part of the Western diet. These substances are added to foods to improve their texture, consistency and shelf life. Along with the increased use of processed foods, we are witnessing an increase in the incidence of Inflammatory Bowel Diseases and behavioral disorders for which there seems to be no rational explanation.
The list of emulsifiers included in the foods we eat is long, and research into the health effects of these molecules is still in its infancy. Popular food emulsifiers include Xanthan Gum, Maltodextrin, Soy Lecithin, Carrageenan, Carboxymethylcellulose, Polysorbate-80, Aluminosilicates and Titanium dioxide. Studies have shown that some of these can alter the gut microbiota, disrupting the delicate balance of microorganisms that live in our bowels.
The microbiota is that diverse collection of bacteria that increasingly are being recognized as an important “organ” in the homeostasis of the human body. It plays important roles in the integrity of the bowel wall and in the breakdown of indigestible fibers we consume in our diets, The fermentation of fiber in the large bowel produces important molecules, called SCFAs (Short-Chain Fatty Acids) that, among other things, regulate the immune system. SCFAs are absorbed through the bowel wall where they travel to the liver and act as an energy source for liver cells. Those that are not used up in the liver can enter the general circulation and travel to the brain and brainstem, where they influence the production of neurotransmitters important for a variety of central nervous system functions.
Food emulsifiers alter the gut microbiota, so that the proportion of beneficial bacteria is decreased and, instead, a greater portion of harmful bacteria take up residence in the bowel. This results in a lower production of those very important SCFAs, immune dysregulation, and a chronic inflammatory state. The inflammation caused by this alteration of the gut microbiota is low grade, meaning that there is a systemic increase in inflammatory cytokines, but there is no accumulation of inflammatory cells in the bowel wall. This chronic inflammation can eventually lead to Inflammatory Bowel Diseases, such as Ulcerative Colitis and Crohn’s disease.
This has been proven in animal studies involving mice. Mice fed Carboxymethylcellulose and Polysorbate 80 develop bowel inflammation accompanied by a change in their gut microbiota called dysbiosis. And when fecal material from these mice was transplanted into the bowel of mice not fed these emulsifiers, they too developed bowel inflammation. This suggests that the change in microbiota of the gut is the triggering factors in bowel inflammation.
The chronic bowel inflammation predisposes to the development of bowel cancer. Although the experiments were performed in mice, the observation that there is a growing incidence of Inflammatory Bowel Disease and Bowel Cancer in parallel with the increasing consumption of food emulsifiers presents a powerful argument to avoid highly processed foods containing emulsifiers. And diets restricting the intake of emulsifiers have been shown to induce remission in childhood Crohn’s disease.