The Association Between Sugar-Sweetened Beverage (SSB) Consumption and Gut Microbiota Composition and Related Metabolites in Adults: A Systematic Review

Background. Sugar-Sweetened Beverages (SSB) are a major source of dietary sugars worldwide. Emerging evidence suggests that dietary factors, including sugar intake, may influence the composition of the gut microbiota, which plays a crucial role in human physiology. However, the relationships between habitual SSB intake, gut microbiota composition, and related metabolites in adults remain insufficiently studied. Aim. This systematic review aimed to synthesize available evidence on the associations between SSB consumption, gut microbiota composition, and related metabolite profiles in adults, while identifying methodological differences and gaps in literature. Material and methods. A systematic search identified observational studies investigating SSB intake and gut microbiota or metabolite outcomes in healthy adult populations. Results. Higher SSB intake was consistently associated with alterations in gut microbial composition, including shifts in the Firmicutes: Bacteroidetes ratio. Changes included reductions in short-chain fatty acid producing species including Eubacterium eligens, Ruminococcus callidus, and several Clostridium species. Metabolomic analyses revealed changes in branched-chain amino acids, aromatic amino acids, glycerophospholipids and bile acids with distinct patterns observed for specific SSB types. Overall, 56 serum metabolites were significantly related to SSB intake and implicated in diabetes risk. SSB was also linked to higher visceral adiposity index, total and LDL-cholesterol. Added sugar intake was positively associated with the genus Lachnobacterium. Conclusions. Habitual SSB consumption may influence gut microbial composition and related metabolites in adults, contributing to metabolic dysregulation. The limited number of studies, methodological differences and observational nature of available evidence, highlight the need for interventional studies and the necessity of standardized methods.