Gut-Friendly Eating Linked to Fewer Kidney Stones

Kidney-stone disease is a major health problem around the world. One way to study diet looks at the gut. The Dietary Index for Gut Microbiota, or DI-GM, estimates how food choices may affect gut microbes. In Chinese adults, the key question was simple: could a higher DI-GM score be linked with a lower chance of nephrolithiasis?

The research used the Shenyang sub-cohort of the Tianjin Chronic Low-Grade Systemic Inflammation and Health cohort. It included 278 adults with nephrolithiasis and 556 healthy adults without the condition. Each patient was paired with two healthy participants by age and sex. Food habits were recorded with a validated food frequency questionnaire. The team then calculated DI-GM scores.

Statistical tools were used to test the link. Conditional logistic regression adjusted for multiple factors. Restricted cubic splines checked whether the pattern curved. Separate checks were also done by age and sex.

The main result was clear. People with higher DI-GM scores had lower odds of nephrolithiasis. After adjustment, the risk fell step by step as scores rose, and the trend was statistically significant. Those with scores of 8 or more had 83% lower odds than people scoring 0 to 5. The odds ratio was 0.17, with a 95% confidence interval of 0.08 to 0.36.

The lower-odds pattern appeared in the age and sex groups checked. The data did not show a curved or non-linear relationship. The test for non-linearity was above 0.05. This means the score did not seem to change direction at one point. The result should be treated as an association, not proof of cause. It does suggest that diet patterns aimed at gut health may matter. Future prospective studies are needed to test whether the link holds over time.