Food Additives, Gut Microbiota, and Irritable Bowel Syndrome: A Hidden Track

Abstract

The interactions between diet, gut microbiota, and irritable bowel syndrome (IBS) have many complex mechanisms that are not fully understood. Food additives are one component of the modern human diet that deserves attention from science and government policies. This review aims at identifying the current knowledge about the impact of food additives on gut microbiota and their potential role in the development of IBS. To date, few data on the effect of food additives on gut microbiota in IBS patients are available. However, exposure to food additives could induce the dysbiosis and dysregulation of gut homeostasis with an alteration of the gut barrier and activation of the immune response. These microbial changes could exacerbate the gut symptoms associated with IBS, such as visceral pain, low-grade inflammation, and changes in bowel habits. Some additives (polyols) are excluded in the low fermentable oligo-, di- and monosaccharide, and polyol (FODMAP), diets for IBS patients. Even if most studies have been performed in animals, and human studies are required, many artificial sweeteners, emulsifiers, and food colorants could represent a potential hidden driver of IBS, through gut microbiota alterations. Consequently, food additives should be preventively avoided in the diet as well as dietary supplements for patients with IBS.

Keywords: IBS; artificial sweeteners; carboxymethylcellulose; emulsifiers; food additives; food preservatives; microbiota; personalized medicine; polyols; polysorbate-80; titanium dioxide.

Figure 1

Food additives, gut microbiota, and irritable bowel syndrome (non-exhaustive list of food additives). Abbreviations: E171, titanium dioxide; E202, potassium sorbate; E211, sodium benzoate; E251, sodium nitrate; E420, sorbitol; E433, polysorbate 80; E466, carboxymethyl cellulose; E481, sodium stearoyl-2-lactylate; E950, acesulfame potassium; E951, aspartame; E954, saccharin; E955, sucralose; E961, neotame; E965, maltitol; E966, lactitol; LCN2, lipocalin-2; IBS, irritable bowel syndrome; LPS, lipopolysaccharides; Mucin-2, oligomeric mucus gel-forming protein encoded by the MUC2 gene; NFκB, nuclear factor-kappa B; PAMPs, pathogen associated molecular patterns; Reg T cells, regulatory T cells; TNF, tumor necrosis factor.