How does the frequency of grocery shopping trips impact a household’s diet quality? Researchers in Chicago sought to answer this question in a new study examining both grocery shopping habits and household food inventories.
The study, published in the Journal of the Academy of Nutrition and Dietetics, collected data from the Study on Children’s Home Food Availability Using TechNology between 2014 and 2016.1 Ninety-seven low-income families from African-American and hispanic families participated in the study. Diets were scored using home food inventories and a 24-hour history of what individuals in the household ate. Household food quality was matched to grocery shopping frequency—monthly, twice per month, three times per month, or weekly.
Researchers sought to investigate how the frequency of grocery shopping in a household impacted the overall diet of that household, and individually the members within that household—specifically young children.
“Grocery shopping frequency could be an important contributor to the types and quality of foods families bring into their homes,” says Angela Kong, PhD, MPH, RD, co-author of the study and clinical assistant professor of nutrition at the University of Illinois at Chicago College of Applied Health Sciences. King is also a researcher and fellow at the Institute for Health Research and Policy. “We found that the diet quality of foods in the home, based on the Healthy Eating Index Score, was poorer in households that grocery shopped once a month compared to households that shopped more frequently.”
The National Health and Nutrition Examination Survey, conducted from 1999 to 2016, found that although diets overall have improved with time, the majority of Americans still have poor diet quality. Higher income Americans have fared better, but there needs to be more work on improving diets overall—and specifically those of young children who eat the majority of their meals at home.
More frequent grocery shopping is associated with a higher intake of fruits and vegetables, but little else is known about overall diet quality in regard to grocery shopping frequency. The researchers analyzed grocery shopping patterns and household food inventories to get a bigger picture view, and found several trends.
In children, sodium scores were higher in households that shopped for groceries twice a month, but fruit and vegetable consumption was higher in households that shopped three or four times per month rather than those who shopped once per month. Overall, in households where grocery shopping happened more often, diet scores for the household were better.
“There were a greater number of households that were Black/African-American that reported shopping only once per month. The number of monthly shoppers who could drive themselves to the store was significantly less than households that shopped more frequently,” Kong says, adding that adjustments were made for these variables in the study analysis.
What the study did not investigate was whether grocery shopping frequency was impacted by availability—a problem in food deserts where it can be difficult to get access to fresh, healthy foods.
“Most of the households in our study resided in similar neighborhoods. We think transportation access could be a key contributor to a household’s ability to shop more frequently,” she says, adding this would require further investigation.
Researchers also did not ask why families shopped when they did. Was it a transportation problem? Scheduling? Budgets? That question hasn’t been answered yet, Kong says.
“We were able to conclude that shopping less frequently causes households to bring foods of poorer diet quality into their homes,” Kong says. “Future research is needed to understand this relationship better. Also, we would like to examine the potential influence car access has on shopping frequency and diet quality.”
Kong says she hopes the study highlights the fact that how often a household can grocery shop has a big impact on the types of food they bring into their home.
“In the context of clinical practice, it could be a conversation worth having between providers and patients,” she says.
1. Banks J, Fitzgibbon M, Schiffer L, et al. Relationship between grocery shopping frequency and home- and individual-level diet quality among low-income racial or ethnic minority households with preschool-aged children. J Acad Nutr Diet. 2020;120(10):1706-1714.e1. doi:10.1016/j.jand.2020.06.017