An investigation of diet quality across racial groups in the United Kingdom and United States considering nutritional adequacy, disease risk, and environmental sustainability: a secondary analysis of NDNS and NHANES datasets.

Diet indices are quantitative assessments of the quality of population intake. Understanding diet quality is crucial to support health and well-being; however, knowledge of diet quality across racial groups is limited. To examine diet quality of acial groups 'White', 'Black', 'Asian', and 'Other' in the United Kingdom (U.K.) and United States (U.S.), U.K. and U.S. national survey data were used to calculate Alternative Healthy Eating Index (AHEI-2010), Diet Quality Index-International (DQI-I), and EAT-Lancet scores. ANCOVA tests compared median total quality scores across racial groups adjusting for covariates. Kruskal-Wallis tests examined differences in individual component scores. Spearman correlations identified association of diet quality scores across indices. Highest diet quality scores were reported for U.K. and U.S. Asian groups. Most noticeable differences were apparent between U.S. Asian and White/Black groups (62% Asians within highest tertile of AHEI-2010 score vs. 29% Whites; P < 0.001). All racial groups demonstrated poor diet quality in terms of sustainability; EAT-Lancet scores were <40% of maximum total score for U.S. White, Black, and Other groups. AHEI-2010 diet quality scores were moderately associated with EAT-Lancet scores, evident across all groups (r = 0.53-0.65; P < 0.001). There is a need for all groups to increase intake of wholegrains, especially Black groups (mean Wholegrain score for U.S. Black group within DQI-I was 0.60 (maximum score of 5)) as demonstrated within AHEI-2010, DQI-I, and EAT-Lancet component scores. Additionally, increased intake of vegetables and legumes and decreased intake of processed and red meat would improve the adequacy, healthiness, and sustainability of U.K. and U.S. racial diets.