Understanding the association of food insecurity and nutrition insecurity with diet quality: a cross-sectional analysis of 2 national samples

Background: Food insecurity is associated with poor diet quality. However, nutrition security may better predict diet quality as it specifically measures healthy food access. Objectives: This study aims to examine the associations between food security, nutrition security, and joint food and nutrition security status with diet quality. Methods: Data came from 2 cross-sectional surveys of United States adults (n = 4554) and Supplemental Nutrition Assistance Program (SNAP) participants (n = 1463). For United States adults, food security was measured with the 18-item Household Food Security Survey Module, and diet quality was measured with the Prime Diet Quality Score (PDQS). For SNAP adults, food security was measured with the USDA's 6-item Food Security Survey, and diet quality was measured with the rapid PDQS (rPDQS). Nutrition security was measured with the Center for Nutrition and Health Impact's Household Nutrition Security (HNS) in both samples. Linear regression models analyzed the relationship between food and nutrition security and diet quality separately and jointly, adjusting for sociodemographic covariates. Results: In the United States adult sample, 52.8% were food and nutrition secure (FS/NS), 16.4% were food insecure and nutrition secure (FI/NS), 4.2% were food secure and nutrition insecure (FS/NI), and 26.6% were food and nutrition insecurity (FI/NI). In the SNAP sample, 24.1% were FS/NS, 27.5% were FI/NS, 1.4% were FS/NI, and 46.9% were FI/NI. After multivariate adjustment, food insecurity was associated with lower diet quality in both samples [United States adults: β = −1.2 PDQS points; 95% confidence interval (CI): = −1.9, −0.54; SNAP sample: β=−0.92 rPDQS points; 95% CI: −1.7, −0.14]. Nutrition insecurity was not associated with lower diet quality for either sample. In both samples, joint food and nutrition insecurity was associated with the lowest diet quality compared with other groups. Conclusions: Further research is needed to understand the utility of the HNS because food insecurity was more strongly associated with lower diet quality than nutrition insecurity.