Trends in Adiposity and Food Insecurity Among US Adults

IMPORTANCE: Food insecurity is a pervasive public health issue in the US that is associated with greater body weight. OBJECTIVE: To examine national trends in food insecurity among US adults from 1999 to 2016 according to surrogate measures of adiposity (body mass index [BMI] and waist circumference [WC]). DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study analyzed nationally representative data obtained from nine 2-year cycles (1999 to 2000 through 2015 to 2016) of the National Health and Nutrition Examination Survey in the US. The sample comprised adult survey participants aged 20 years or older. Data analyses were performed from July 1, 2019, to March 31, 2020. MAIN OUTCOMES AND MEASURES: The primary outcome was food insecurity. Data on BMI (calculated as weight in kilograms divided by height in meters squared) were categorized as follows: normal weight (BMI, <25), overweight (BMI, 25-29.9), and obese (BMI, ≥30). Data on WC were categorized as follows: less high risk (men: ≤102 cm; women: ≤88 cm) or high risk (men: >102 cm; women: >88 cm). Food insecurity prevalence by adiposity was further analyzed using key demographic characteristics, including sex and race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, and Other). RESULTS: Among the 46 145 adults in the final sample, the mean (SD) age was 46.9 (0.2) years. Of this sample, 23 957 were women (52.0%; 95% CI, 51.6%-52.5%) and 20 825 were non-Hispanic White adults (68.8%; 95% CI, 66.6%-71.0%). The estimated prevalence of food insecurity was 18.2% (95% CI, 15.3%-21.2%) in the 2015 to 2016 cycle, a statistically significant change from 8.7% (95% CI, 7.3%-10.2%) in the 1999 to 2000 cycle. Among all adiposity categories, food insecurity prevalence significantly increased from the 1999 to 2000 cycle to the 2015 to 2016 cycle. The prevalence of food insecurity was highest in adults with obesity (22.6%; 95% CI, 19.5%-25.8%; P for trend <.001). For both men and women, food insecurity prevalence significantly increased from the 1999 to 2000 cycle (men: 8.8% [95% CI, 6.9%-10.6%]; women: 8.7% [95% CI, 7.0%-10.5%]) to the 2015 to 2016 cycle (men: 17.2% [95% CI, 14.1%-20.2%]; women: 19.2% [95% CI, 16.2%-22.2%]; P for trends <.001). For non-Hispanic White and non-Hispanic Black adults, food insecurity prevalence increased from the 1999 to 2000 cycle (non-Hispanic White: 6.0% [95% CI, 4.0%-8.0%]; non-Hispanic Black: 12.4% [95% CI, 9.6%-15.2%]) to the 2015 to 2016 cycle (non-Hispanic White: 13.0% [95% CI, 9.8%-16.3%]; non-Hispanic Black: 29.1% [95% CI, 24.2%-34.0%]; P for trends <.001). For Hispanic adults, food insecurity prevalence significantly increased in those with obesity (1999-2000: 19.1% [95% CI, 12.0%-26.1%]; 2015-2016: 37.6% [95% CI, 33.7%-41.5%]; P for trend ≤.001) and in both less-high-risk WC (1999-2000: 19.6% [95% CI, 12.8%-26.4%]; 2015-2016: 32.5% [95% CI, 27.3%-37.7%]; P for trend = .02) and high-risk WC categories (1999-2000: 19.3% [95% CI, 12.7%-25.9%]; 2015-2016: 36.7% [95% CI, 31.7%-41.7%]; P for trend <.001). CONCLUSIONS AND RELEVANCE: In this cross-sectional study, the estimated prevalence of food insecurity appeared to increase from 1999 to 2016 and across all levels of adiposity. These results suggest the need for multidisciplinary approaches to address the association between food insecurity and obesity in the US.