IMPORTANCE: Accurate and practical measures of nutrition security are needed to assess and monitor its prevalence and to identify its associated risk factors in the US. OBJECTIVE: To propose a nutrition security measure derived from combining self-assessed food security and diet quality indicators available in the National Health and Nutrition Examination Survey (NHANES) and to assess the prevalence and associated sociodemographic and health factors of nutrition security. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study used data from 6 cycles of NHANES, which collects data on general health status and behaviors, dietary intake, physiological measurements, and sociodemographic characteristics, conducted from 2007 to 2018. All participants were adults aged 20 years or older. Statistical analysis was performed between October 2023 and April 2024. EXPOSURES: Sociodemographic and health characteristics, including age, sex, race and ethnicity, marital status, household size, presence of children in the household, educational level, poverty to income ratio (PIR), Supplemental Nutrition Assistance Program (SNAP) participation, weight status, chronic conditions, and health insurance coverage. MAIN OUTCOMES AND MEASURES: A nutrition security measure was derived from combining self-assessed food security, measured using the US Department of Agriculture Household Food Security Survey Module, and self-rated diet quality indicators. Four nutrition security status categories were created from dichotomized food security and diet quality measures: food secure with high diet quality (FSHD), food secure with low diet quality (FSLD), food insecure with high diet quality (FIHD), and food insecure with low diet quality (FILD). Only respondents classified as FSHD were considered to be nutrition secure. RESULTS: The unweighted analytic sample included 28 898 NHANES participants. The weighted mean [SD] age of participants was 47.3 [14.5] years
51.9% (weighted) of the sample was female
11.1% identified as Black, 13.6% as Hispanic, and 67.4% as White individuals
and 35.6% of those surveyed were classified by the proposed measure as nutrition insecure (ie, FSLD, FIHD, or FILD). Of these participants, 20.2% (95% CI, 19.4%-21.0%) were categorized as being nutrition insecure due to FSLD, 8.4% (95% CI, 7.8%-9.1%) due to FIHD, and 7.0% (95% CI, 6.4%-7.6%) due to FILD. The remaining 64.4% (95% CI, 63.2%-65.7%) were classified as FSHD (ie, nutrition secure). Younger age (20-44 years: average marginal effect [AME], -0.193
95% CI, -0.217 to -0.168), low income (PIR <
1.30: AME, -0.111
95% CI, -0.136 to -0.085), lower educational level (≤high school diploma: AME, -0.135
95% CI, -0.156 to -0.114), racial and ethnic minority status (Hispanic: AME, -0.054
95% CI, -0.075 to -0.032), SNAP participation (AME, -0.073
95% CI, -0.099 to -0.047), obesity (AME, -0.118
95% CI, -0.138 to -0.097), and self-reported fair or poor general health (AME, -0.239
95% CI, -0.260 to -0.217) were factors associated with nutrition insecurity. CONCLUSIONS AND RELEVANCE: This cross-sectional study proposed a feasible and practical measure for assessing and monitoring nutrition security using validated measures in the NHANES. This study laid the groundwork for exploring other national datasets and performing regular data collection of key dimensions for nutrition security assessment and monitoring in the US.