the effect of dietary glycemic index on inflammatory biomarkers: a systematic review with consideration of confounders

Introduction: the glycemic index (gi) and inflammation are associated with several diseases; however, the relationship between gi and inflammation remains unclear. in this systematic review, the authors hypothesize that gi influences inflammatory biomarkers but can be significantly affected by unrecognized statistical confounders. methods: a comprehensive search was made in sciencedirect, web of science, pubmed, directory of open access journals (doaj), and google scholar from 2010 to april 2022 using mesh and un-mesh keywords. preferred reporting items for systematic review and meta-analysis (prisma) were used. results: out of 24,577 studies, 14, including one master's thesis, were included in this review. seven of these studies were conducted on individuals with a disease, six were on healthy or obese individuals without other illnesses, and one focused on pregnant women. il-6 was measured in 8 studies, tnf-α in 7, crp in 6, and hs-crp in 2. five well-designed studies confirmed that gi can influence inflammation, while seven found no association. several unaddressed confounders and limitations were identified across the studies. the primary factors affecting the results were dietary patterns, metabolic factors, and food processing. conclusion: based on the results, evidence supports a slight effect of gi on inflammatory biomarkers. the bias risk in different studies is high. more studies are required, and this review provides essential considerations to lower the bias risks for further studies.