Whole Grain and Refined Grains: An Examination of US Household Grocery Store Purchases.

Background: The health benefits related to intake of whole grain foods are well established. Consumption of whole grains in the US population is low, and whole grain content can vary greatly depending upon the specific products that are purchased.

Objectives: To examine the proportion of products purchased by US households containing whole grain and refined grain ingredients using time-specific food composition data, and examine whether purchases differ between income, race or ethnicity, and household make-up.

Methods: Nationally representative Nielsen Homescan 2018 data were used. Each barcoded product captured in Nielsen Homescan 2018 was linked with ingredient information using commercial nutrition databases in a time-relevant manner. Packaged food products containing whole grain ingredients, refined grain ingredients, neither, or both were identified. The percentage of packaged food products containing whole grain and refined grain ingredients purchased by US households was determined overall, by demographic subgroup, and by food category.

Results: The proportion of packaged food purchases containing refined grain ingredients was significantly higher than whole grain ingredients (30.9% compared with 7.9%; P < 0.0001). Lower income households and households with children purchased a significantly higher proportion of products containing refined grain ingredients, with no nutritionally meaningful racial or ethnic differences observed. Concerningly, across all demographic subgroups >90% of bread purchases contained refined grain ingredients, and the 5 categories with the largest proportion of whole grain ingredients contributed to <20% of overall US household packaged food purchases.

Conclusions: US households are purchasing a significantly higher proportion of packaged food products containing refined grain ingredients than whole grain ingredients. Future policy changes are needed to provide incentives and information (e.g., front-of-pack labels) to aid in encouraging manufacturers to increase whole grain product offerings while decreasing refined grain offerings, and to encourage consumers to substitute away from refined grain products toward whole grain products.