Factors and Mechanisms Underlying Individual Differences in Intestinal Susceptibility to Dietary Emulsifiers: A Review

Dietary emulsifiers, common in processed and ultra-processed foods, improve food texture and shelf life but may affect gut health by interacting with the microbiota and intestinal barrier. While emulsifiers have long been considered safe, growing evidence links their presence in ultra-processed foods to chronic disease risk. This review aims to evaluate the current understanding of the factors and mechanisms underlying individual differences in intestinal mucosal susceptibility to dietary emulsifiers. A search of PubMed and Embase through February 2026 identified eight relevant studies. Overall, the available evidence indicates a heterogeneous and highly individualized host response to dietary emulsifiers. These differences appear to be strongly influenced by the gut microbiota and its functional properties, while animal studies further suggest that host factors such as sex-related differences in microbial composition may also contribute to variability in response. Importantly, not all emulsifiers have the same effects, underscoring compound-specific impacts on gut physiology. The findings demonstrate that sensitivity to dietary emulsifiers varies substantially between individuals, challenging the long-standing assumption that these additives are universally safe. Given the multifactorial nature of this susceptibility, particularly the role of the gut microbiota, future research should adopt an integrative approach that combines microbial profiling with host genetics, immune responses, and early-life exposures. Such efforts will be essential to identify at-risk individuals and to inform more personalized dietary recommendations aimed at preserving intestinal health and reducing disease risk. Importantly, there is a clear need for larger, well-powered studies that can validate and expand upon these initial observations.