Fried food consumption-related gut microbiota is associated with obesity, fat distribution and cardiometabolic diseases: results from two large longitudinal cohorts with sibling comparison analyses.

Background: In prospective cohort studies, the relationship between fried food consumption, gut microbiota, obesity, and cardiometabolic diseases remains unknown.

Objective: We aimed to explore associations of fried food consumption with gut microbiota and associations of fried food consumption-related microbiota with obesity and related disorders.

Methods: We analyzed 6,637 individuals from the WELL-China cohort (baseline 2016-2019) and 3,466 from the Lanxi cohort (baseline 2017-2019), with follow-up until June 24, 2024. Face-to-face interviews provided data on fried food consumption and other covariates. Analysis of 16S rRNA data from fecal samples collected at baseline identified microbial genera. Body composition was evaluated using dual-energy X-ray absorptiometry (DXA). The Microbiome Multivariable Associations with Linear Models (MaAsLin) helped identify genera associated with frequency of fried food consumption in the cross-sectional analysis. Cox regression models examined the relationship of fried food consumption-related microbiota with cardiometabolic diseases during follow-up. Sibling comparison analyses were used to control for unmeasured familial confounders using the between-within (BW) model.

Results: Twenty-five microbial genera were significantly associated with fried food consumption frequency. Using these genera, we constructed a fried food consumption-related microbiota index. Meta-analysis of both cohorts found a positive relationship of this index with overall adiposity measures (BMI) (β coefficient, 0.26; 95% confidence interval (CI), 0.19-0.32) and central fat distribution parameters (including android-gynoid fat ratio (β, 1.48; 95% CI, 1.14-1.82)). Longitudinal analyses indicated that a higher fried food consumption-related microbiota index was linked to a higher risk of developing cardiometabolic diseases, with adjusted hazard ratios (95% CI) of 1.16 (1.07-1.27) for diabetes and 1.16 (1.06-1.26) for major adverse cardiovascular events. Sibling comparison analyses yielded similar results.

Conclusions: Fried food consumption-related microbiome is associated with a higher risk of obesity, central fat distribution, and cardiometabolic diseases, emphasizing the importance of dietary choices in the management and prevention of chronic diseases.