The effects of acute carbohydrate supplementation on inflammatory cytokines in individuals performing different exercise intensities: a systematic review and meta-analysis

Objective: This study aims to conduct a systematic review and meta-analysis to examine the effects of carbohydrate supplementation on inflammatory cytokines under different exercise intensities, and to explore the interaction between carbohydrate types and exercise intensity in the regulation of inflammation. Methods: A systematic search of PubMed, EBSCOhost, Cochrane, Web of Science and CNKI. Twenty eligible studies were included, reporting on key inflammatory cytokines: IL-6, TNF-α, IL-10, IL-1β, and IL-1ra. Results: A total of 20 studies (n = 286 participants) were included. Carbohydrate supplementation significantly reduced levels of IL-6, IL-1ra and IL-10, while TNF-α levels increased significantl, and changes in IL-1β were not significan. Subgroup analysis revealed that the combination of "glucose, sucrose" had the strongest inhibitory effect on IL-6 during high-intensity exercise, while "glucose, fructose" most significantly increased TNF-α during moderate-intensity exercise. Anti-inflammatory cytokines IL-10 and IL-1ra showed a downward trend under moderate-intensity supplementation, suggesting possible suppression of negative feedback mechanisms in inflammation. Conclusion: Carbohydrate supplementation exerts a significant modulatory effect on exercise-induced inflammatory responses, with the direction and magnitude influenced by carbohydrate type and exercise intensity. In the future, the inflammatory regulatory mechanism should be further explored in depth in combination with metabolic status and training background.