Food Insecurity and Gastrointestinal Health: Examining Links Between Food Security, Constipation, and Diarrhea in the National Health and Nutrition Examination Survey

Purpose Food insecurity impacts health in a multifactorial fashion, but the relationship with bowel habits is poorly understood. We aimed to examine the association between food insecurity status and bowel habits in a large cohort of U.S. adults. Methods We analyzed adults (age 20–59 years) who completed both the bowel habits questionnaire and the food security survey module in the National Health and Nutrition Examination Survey over a 6-year period from 2005 to 2010 (n = 9,637). Constipation and diarrhea were defined according to Bristol stool form and/or stool frequency. Adjusted odds ratios (AORs) for likelihood of constipation or diarrhea were estimated in a multinomial logistic model across levels of food security. Results Constipation and diarrhea were more prevalent among individuals with lower food security compared to those with full food security (constipation: 19.6% vs. 14.2%; diarrhea: 14.8% vs. 11.0%; both p < 0.0001). Very low food security was associated with nearly twice the odds of constipation (OR 1.90, 95% CI: 1.48–2.42) and 54% greater odds of diarrhea (OR 1.54, 95% CI: 1.22–1.93). After stepwise adjustments for demographic, BMI, and dietary factors, these associations persisted (constipation AOR: 1.39, 95% CI 1.06–1.83; diarrhea AOR: 1.27, 95% CI 1.00–1.61). Adjustment for depression attenuated the significance of this association (constipation AOR: 1.25, 95% CI 0.97–1.63; diarrhea AOR: 1.16, 95% CI 0.90–1.51), suggesting a potential mediating role. Conclusion In a national representative sample of community-dwelling US adults, decreasing food security was associated with increased odds of constipation and diarrhea. However, when multivariable adjustment included depression, this impact was attenuated, suggesting that depression may confound this relationship.