Nutrition quality of food purchases varies by household income: the SHoPPER study

BackgroundLower household income has been consistently associated with poorer diet quality. Household food purchases may be an important intervention target to improve diet quality among low income populations. Associations between household income and the diet quality of household food purchases were examined.MethodsFood purchase receipt data were collected for 14days from 202 urban households participating in a study about food shopping. Purchase data were analyzed using NDS-R software and scored using the Healthy Eating Index 2010 (HEI 2010). HEI total and subscores, and proportion of grocery dollars spent on food categories (e.g. fruits, vegetables, sugar sweetened beverages) were examined by household income-to-poverty ratio.ResultsCompared to lower income households, after adjusting for education, marital status and race, higher income households had significantly higher HEI total scores (mean [sd]=68.2 [13.3] versus 51.6 [13.9], respectively, adjusted p=0.05), higher total vegetable scores (mean [sd]=3.6 [1.4] versus 2.3 [1.6], respectively, adjusted p<.01), higher dairy scores (mean [sd]=5.6 [3.0] versus 5.0 [3.3], p=.05) and lower proportion of grocery dollars spent on frozen desserts (1% [.02] versus 3% [.07], respectively, p=.02).ConclusionsLower income households purchase less healthful foods compared with higher income households. Food purchasing patterns may mediate income differences in dietary intake quality.Trial registrationClinicalTrials.gov identifier: NCT02073643.