Fig. 1

Study design and analytical method. A This study was based on the Guangzhou Nutrition and Health Study. A total of 741 stool samples were first collected between 2014 and 2017. Among them, 505 follow-up stool samples were repeatedly collected between 2018 and 2019. Metadata including sociodemographic factors, anthropometric parameters, lifestyle factors, medication use, habitual diet, and insulin resistance-related phenotypes were collected for the 505 participants. Shotgun metagenomic sequencing was performed for these 505 paired stool samples. After excluding participants who met the exclusion criterion and performing quality control for species, 426 participants with 171 species remained for subsequent analysis. B The cross-lagged panel analysis of BMI and gut microbiota. ρ1 and ρ2 are cross-lagged path coefficients; r1 and r2 are tracking correlations; r3 is the synchronous correlation between BMI and gut microbiota at baseline. C Gut microbiota mediates the association between overweight/obesity and insulin resistance