A USC study has found a good reason to check the expiration date on market foods.

Researchers, working with residents in lower-income areas of Los Angeles, counted at least one expired poultry, beef or dairy product in about a third of the store visits made over a one-year period.

Participating residents kept track of their own market visits and recorded expired foods in certain designated food categories during the Neighborhood Food Watch project. Data collected also revealed that in 18 percent of the visits, residents found at least three expired poultry, beef and dairy items.

“This project builds on our previous research into the disparity of food options in our communities,” said USC School of Policy, Planning, and Development professor LaVonna Lewis. “The results in this particular study reflect the lack of access to quality food products that have been documented nationally in regards to African-American communities and other residents who live in low-income areas.”

Lewis presented some of the project’s data Sept. 23 at the 2009 California REACH US Conference, which was sponsored by REACH US grantees such as the Community Health Councils Inc. Community Health Councils, which addresses health care inadequacies in communities, has had a 10-year research partnership with USC.

Data collection for the Neighborhood Food Watch campaign, which started in April 2008 and ended in February of this year, was done by 90 members of the community who kept checklists of what they encountered during their food shopping trips. This is a method of inquiry called community-based participation research.

A total of 657 checklists were received from the residents and 432 of the lists were centered on five unnamed stores that Lewis said included some well-known supermarket chains.

Participants in the campaign were recruited in areas where researchers suspected expired foods might be found, but the study did not place a geographical limit on the stores visited. The stores primarily were located in the Los Angeles area, but some residents filed reports from stores in other communities, and even out of state.

Looking just at the five unnamed grocery stores, the data for expired poultry ranged from 19.2 percent to 39.5 percent. The range was 20 percent to 41.8 percent for expired beef, and for milk and dairy products, the range was 26 percent to 45.4 percent.

The data showed that most of the stores visited by residents were providing sufficient access to special diet foods. Low sodium and sugar-free products were found in at least 95.4 percent of all stores, and soy/lactose free products were found in 96.5 of all stores.

Lewis said that involving community members in the research is one way of enhancing participation and minimizing distrust among typically marginalized groups. The aim is to build partnerships by training residents in research skills and helping them to identify problems in their own community.

In this particular survey, 82.8 percent of the Neighborhood Food Watch campaign participants were African American, 10.6 percent were Hispanic/Latino and 90.2 percent were women.

Lewis is in the process of preparing data related to the expired food projects for formal submission to academic journals.

USC researchers at the School of Policy, Planning, and Development – including Lewis, professor David Sloane and professor Peter Robertson – have been actively involved in conducting research into the community’s health and diet disparities for more than a decade.

The first phase of the ongoing project started out with community members identifying specific health and nutrition concerns. The second phase focused on education, prevention and assessment, such as documenting health food options in markets and restaurants in lower-income areas of Los Angeles. The current phase is exploring ways to build on the findings of these studies through solutions, such as creating a hotline to report expired food.

“The quality of foods available to residents – whether it’s in a grocery store or a restaurant – has a tremendous impact on what residents choose to eat, and it also has the potential to affect their long-term health,” said Sloane, who has been studying the role of environments in health disparities in cardiovascular disease and diabetes among African-Americans.