Dietary Index for Gut Microbiota and Leisure Time Physical Activity: The Potential Combined Protective Impact on...

Emerging evidence highlights the gut microbiome's role in hypertension via microbial metabolites and endothelial dysfunction, while the Dietary Index for Gut Microbiota (DI-GM) quantifies diet quality for microbiota health. In addition, leisure-time physical activity (LTPA) also reduces blood pressure, but their combined impact on population-level hypertension remains unclear. Therefore, this study explores the individual and joint effects of DI-GM and LTPA on hypertension risk. To address this objective, we conducted a cross-sectional study analysis of data from 27,643 adults in the National Health and Nutrition Examination Survey (NHANES 2007-2020). Excluding individuals with incomplete data, key variables included the DI-GM and LTPA pattern (categorized by intensity, frequency, and regularity; regularly active defined as > 2 days/week). Weighted logistic regression models and restricted cubic splines (RCS) evaluated independent, joint, and non-linear associations of DI-GM and LTPA with hypertension, adjusting for covariates. The results showed that higher DI-GM scores and greater weekly LTPA were inversely correlated with hypertension risk, exhibiting dose-dependent patterns (16% lower odds for DI-GM ≥ 6 vs. lowest groups; 16%-24% lower odds for LTPA (≥ 150 min/week) vs. lowest groups). RCS analysis showed a linear inverse dose-response relationship between DI-GM and hypertension. The regularly active LTPA pattern (> 2 days/week) was linked to a 24% lower risk of hypertension (OR = 0.76, 95% CI = 0.69-0.84), and there was also a significant association observed for the weekend warrior LTPA pattern (1-2 days/week) (OR = 0.80, 95% CI = 0.64-0.99). Notably, joint analysis demonstrated that individuals with DI-GM > 4 scores and LTPA ≥ 150 min/week or regularly LTPA pattern exhibited the lowest hypertension odds. In conclusion, both a high DI-GM score (≥ 6 points) and sufficient LTPA (≥ 150 min/week) were independently associated with reduced odds of hypertension, with their combined effect amplifying protective benefits. Prospective studies are warranted to confirm temporality and causal pathways.