Association between zinc consumption and chronic diarrhea based on NHANES 2005 to 2010 data

Chronic diarrhea is a digestive disorder with a global prevalence ranging from 3% to 20%. The etiology of chronic diarrhea is complex and can be life-threatening in severe clinical cases. Zinc serves as a vital trace element that plays a pivotal role in stabilizing the intestinal barrier and regulating gut flora. However, previous evidence on the association between dietary zinc intake and chronic diarrhea remains limited. We extracted and analyzed questionnaire, laboratory, and dietary data from the National Health and Nutrition Examination Survey database (2005-2010). Dietary zinc intake was categorized into quartiles to explore its potential association with chronic diarrhea. The correlation between zinc intake and the risk of chronic diarrhea was analyzed using complex sample-weighted statistical methods, including weighted t tests, weighted chi-square tests, one-way regression analysis, and multivariate logistic regression analysis. The findings indicated a significant positive correlation between zinc intake and risk of chronic diarrhea across all 3 adjusted continuous variable models. For categorical variables, the highest zinc intake group (Q4) exhibited an elevated risk of chronic diarrhea compared with the lowest intake group (Q1). A 2-piecewise linear model identified an inflection point of 22.647 mg in the relationship between zinc intake and chronic diarrhea, with a positive correlation observed below this threshold and a negative correlation detected above this cutoff. Our study provides novel insights into the association between dietary zinc intake and risk of chronic diarrhea. A 2-piecewise linear model revealed a complex correlation between the 2, under the influence of the threshold effect.