Changes in Diet, Food Insecurity, and Stress After a Minimum Wage Increase

BY Drs. Leah Chapman and Caitlin Caspi

In June 2017, the Minneapolis City Council voted to increase the city’s minimum wage above the state level to $15 an hour. The wage increase was rolled out incrementally each year, and full implementation was set for July 1st, 2022 for large businesses (those with greater than 100 employees) and July 1st, 2024 for small businesses (those with less than 100 employees). This minimum wage policy presented an opportunity for a multisite team of health researchers to take a unique angle on a minimum wage evaluation: What effect might the wage increase have on health outcomes? Could these be measured by following low-wage workers in real-time?

There are numerous pathways by which minimum wage policies have the potential to improve health. For example, many studies in the health literature have found that on average, low-income Americans consume fewer fruits and vegetables and have lower quality diets than higher income Americans. There are many factors that contribute to these disparities in intake, but one important factor is the high cost of healthier foods. Policies that increase lower income Americans’ hourly wage, such as minimum wage ordinances, may increase household income. This increased income could translate into increased purchases and consumption of healthier and more costly foods, such as fruits and vegetables, or other health behaviors or indicators. These changes could occur through processes such as reduced stress or improved food security.

It’s challenging to study wage effects on health by following the same participants over time in a prospective study, but this is what the Wages Study did. The study, funded by the National Institutes of Health, enrolled a cohort of 974 low-wage workers two U.S. cities, Minneapolis, Minnesota, and in a comparison city in which there was no minimum wage increase (Raleigh, North Carolina). The study followed this cohort annually from 2018-2022, measuring various health and economic outcomes including body mass index, dietary intake, food security, stress, hourly wage, household income, and use of federal assistance programs such as Supplemental Nutrition Assistance Program (SNAP).

Our research team used the first two years of data from the Wages Study (in which the minimum wage had increased to $12.25 for large businesses and $11.00 for small businesses) to examine whether the initial implementation of the Minneapolis minimum wage policy was associated with changes in dietary intake (specifically, fruits and vegetables, whole grain-rich foods, and foods high in added sugars). Interestingly, we found that although hourly wages had increased, the minimum wage policy did not lead to changes in dietary intake.

As a follow up analysis, our team examined changes in potential intermediaries of the wage-diet relationship- specifically, food security and perceived stress. Although there are many potential intermediaries of the wage-diet relationship, we focused specifically on food security and stress because of their well-established relationships with wages, income, and dietary intake in the health literature. Numerous studies have shown that income is inversely related to stress, and increased stress can negatively affect diet quality through multiple pathways. For example, stress may promote irregular eating patterns and consuming food for pleasure in the absence of caloric need. However, surprisingly, we found that increased wages also did not lead to changes in food security or stress.

What can we learn from a study like this? First, it’s important to remember that policy effects can take time to show up. A policy change may not lead to significant changes in a targeted outcome during its first year, or even the first several years, of implementation. It is important not to “give up” on a policy if the anticipated changes are not immediately observed, as health behaviors can take months to years to change. Second, behavior change rarely happens in isolation. Minimum wage is just one social determinant of health. If wage increases are implemented without other supportive policies for low wage workers, how much impact can they have? As an example, study participants reported experiencing frequent changes in their SNAP benefits during the first two years of the study. If minimum wage ordinances increase workers’ income, this may also cause a reduction in SNAP benefits, offsetting some of the intended financial benefits of minimum wage ordinances. This is something that the Wages Study is continuing to monitor and study, and it will be extremely important for future research to also carefully study federal assistance programs in the context of minimum wage ordinances.