Abstract MP17: Geographic Variations in Diet Quality Among Adults in the United States

Abstract

Introduction: Prior studies of diet quality in the United States (US) have focused on national estimates and trends. Examining geographic variations in diet quality over time can provide actionable and targeted policy insights. Hypothesis: Diet quality is heterogeneously distributed across US geographical locations with higher diet quality in urban and western and eastern regions. Methods: We included a nationally representative sample of US adults aged 20 years or older with data on 24-hour dietary recall and geocode (N=19,607) from six cycles (2007-2018) of the National Health and Nutrition Examination Survey (NHANES). Exposures are geographic location by rurality, level of urbanization (large, medium, and small), and US census region and calendar year. Outcomes are diet quality measured by the American Heart Association dietary primary (range 0-50; based on total fruits and vegetables, whole grains, fish and shellfish, sugar-sweetened beverage, and sodium); secondary scores (range 0-80; adding nuts/seeds/legumes, processed meat, and saturated fat); the Healthy Eating Index (HEI) 2015 (range 0-50); major dietary components; and poor diet quality. Poor diet was defined according to the AHA secondary score as less than 40% adherence (score <32); intermediate, as 40% to 79.9% adherence (score 32-63.9); and ideal, as at least 80% adherence (score ≥64, respectively). Results: Among rural vs. urban residents, the primary AHA, secondary AHA, and HEI-2015 scores in 2017-2018 were 19.5 (95% CI, 18.9-20.1) vs. 20.6 (95% CI, 20.4-30.0); 35.1 (95% CI, 34.3-35.8) vs. 37.1 (95% CI, 36.7-37.6), and 51.8 (95% CI, 51.0-52.7) vs. 53.9 (95% CI, 53.9-54.4), respectively. The corresponding proportions having poor diet quality for rural vs. urban were 43.1% (95% CI, 40.8%-45.5%) vs. 36.2% (95% CI, 34.8%-37.5%). By region, the AHA secondary score was lowest (34.9; 95% CI, 34.1-35.6) for the South. Similar result patterns were found for the AHA primary and HEI-2015 scores. The proportion of adults having poor diet quality was highest in the South (43.2%; 95% CI, 40.8%-45.6%). Trends in diet quality remained stable from 2007 to 2018. Conclusions: Significant differences in diet quality by rurality, levels of urbanization, and region exist for adults in the US. These differences in diet quality have remained stable from 2007 to 2018. Geographic differences in diet quality—and the consistency of these differences over time—seem to be important in the development of targeted food policy strategies to address regional disparities.