Consumption of Ultraprocessed Foods and Body Fat Distribution Among US Adults

Introduction: The association between ultraprocessed food consumption and body composition and potential variations by sociodemographic factors is unclear. This study aims to examine the cross-sectional associations of ultraprocessed food consumption with imaging markers of body fat distribution in a nationally representative sample of U.S. adults, overall and by sociodemographic strata.Methods: A total of 9,640 men and nonpregnant women aged 20-59 years were included from 4 cycles (2011-2012, 2013-2014, 2015-2016, 2017-2018) of the National Health and Nutrition Examination Survey with valid 24-hour dietary recalls and available whole-body dual-energy x-ray absorptiometry scans. Ultraprocessed foods were identified using the NOVA classification, with percentage energy from ultraprocessed food assessed in quintiles. Primary outcomes were absolute percentage fat (total, android, gynoid), and secondary ones were percentage fat (head, arm, leg, trunk), total abdominal fat (area, mass, volume), subcutaneous adipose tissue (area, mass, volume), and visceral adipose tissue (area, mass, volume). Multivariable-adjusted generalized linear regressions estimated independent relationships of ultraprocessed food intake with body composition overall and by sociodemographic subgroups. Analyses were conducted in September 2022 and January 2023.Results: Ultraprocessed food consumption accounted for more than half (55.5%) of daily energy consumption in this sample. Adults in the highest quintile (>72.1% energy) had 1.60 higher total percentage fat (95% CI=0.94, 2.26), 2.08 higher android percentage fat (95% CI=1.26, 2.89), and 1.32 higher gynoid percentage fat (95% CI=0.71, 1.93) than those in the lowest quintile of ultraprocessed food consumption (<39.4% energy) (all p-trend<0.001). Consistent findings were observed for secondary outcomes. Associations of ultraprocessed food intake with total percentage fat, android percentage fat, and gynoid percentage fat varied by age, sex, race and ethnicity, education, and income. Among those in the highest quintile of ultraprocessed food consumption compared with the lowest quintile counterpart, total percentage fat was 1.85 (95% CI=0.86, 2.84) higher for non-Hispanic White adults and 1.57 (95% CI=0.68, 2.46) higher for Hispanic adults (p-trends<0.001), whereas no difference was observed among non-Hispanic Black adults (-0.22; 95% CI= -0.93, 1.36) (p-trend=0.47) and non-Hispanic Asian adults (0.93; 95% CI= -0.57, 2.42) (p-trend=0.04) (p-interaction=0.001). Associational patterns were similar for android percentage fat and gynoid percentage fat.Conclusions: In a national U.S. sample, higher intake of ultraprocessed food was associated with greater body fat, in particular android fat, and this relationship was most prominent in certain population subgroups. These cross-sectional findings call for prospective and interventional studies to assess the impact of ultraprocessed food on body composition in different population.