Standard toxicology is reassuring: no evidence of genotoxicity, carcinogenicity, or reproductive toxicity, and celluloses are essentially unabsorbed and excreted in feces. The active question is gut health. In mice, low-dose P80 and CMC induced low-grade intestinal inflammation, microbiota shifts, metabolic syndrome and, in susceptible animals, colitis (Chassaing 2015). A double-blind controlled-feeding RCT of 15 g/day CMC for 11 days in healthy adults (Chassaing 2022) reduced microbiota diversity, depleted beneficial metabolites, modestly increased postprandial abdominal discomfort, and in a subset showed bacteria encroaching into the normally sterile mucus layer. Large cohort data are not yet confirmatory for these two additives specifically: the NutriNet-Sante cancer analysis (Sellem 2024) flagged E471 and carrageenans rather than P80/CMC, and the type-2-diabetes analysis implicated several emulsifiers (notably carrageenans). People with inflammatory bowel disease (Crohn's, ulcerative colitis) or irritable bowel syndrome may be the most plausible group to limit intake, though firm clinical guidance does not yet exist. Overall this is an emerging signal, not established harm. Educational only — always check with your doctor or pharmacist before combining Emulsifiers (Polysorbate-80 & CMC) with any medicine.