October 1, 2025
Marai Hayes is an economist who researches the ways that health affects economic outcomes over the course of individuals’ lives, and how health and social policies can reduce inequalities in health and economic opportunities. She joined the Stone Center as a postdoctoral scholar this fall, after receiving her Ph.D. in health policy from Harvard University.
Hayes recently spoke to the Stone Center about her research projects, how she became interested in the connections between health and inequality, and the likely impacts of recent health policy changes at the federal level.
What sorts of topics do you explore in your research?
Hayes: My focus is generally on how health impacts economic outcomes for individuals over their full life course, from early childhood into their prime working years, and then into retirement and late life. To that end, I have some work that looks at childhood health and how it impacts people and their earnings and employment from age 25 to when they’re retiring. I also look at wealth from midlife to old age.
I find that childhood health can be really important and its impact can persist through the full life cycle. I also have some work that looks at childhood health and how it interacts with racial disparities in both income and wealth. Some other interests of mine are related to this relationship between health and the labor market. I have work that looks at the role of health insurance in employment outcomes for individuals, which ties to how health insurance in the U.S. is largely linked to employment, and how that can dictate people’s labor market decisions.
By “childhood health,” do you mean illnesses and diseases such as pediatric cancer and diabetes? Or are you looking at short-term illnesses that are more common and perhaps less dramatic but that can also have lasting effects?
Hayes: At this time, I’m specifically looking at general childhood health measures as well as a previously common short-term illness, though I’m also interested in examining chronic and/or more severe illnesses in the future. My job market paper examines both a general childhood health measure and measles. Measles is an acute — or short-term — illness that is also typically less severe, but it has the potential for some outsized and long-lasting effects on an individual’s health. My general childhood health measure, whether someone rated their health as fair or poor, captures the overall state of someone’s health as a child. I feel that if I find significant effects from either an acute illness like measles or having generally poorer health, it’s likely that chronic or more severe illnesses will have similar or even greater impacts. Going forward, I would like to empirically assess the impacts of higher severity or chronic conditions and how these differ from what I find in my current work. A great feature of my data is that it is possible to identify whether individuals had some of these conditions, like asthma or heart problems, so I think it will be possible to start this work in the near future.
What first brought you to this particular focus within inequality?
Hayes: I was pre-med as an undergrad, and I was always interested in health, healthcare, and health policy. I was also really interested in economics. Those interests combined led to me thinking about how health affects individual economic outcomes, especially labor market outcomes. I think of health as being crucial to a lot of different choices and opportunities that people have in their lives, including on the labor market.
And that, in turn, can be a big determinant of their economic well-being and the opportunities that they have for economic advancement in their lifetime. Beyond that, I’ve also found it notable that health itself can be informed by one’s economic circumstances, and I like thinking about this sort of feedback loop that goes on between health and socioeconomic status where improving one can improve the other, and vice versa.
What made you decide to become an economist rather than a doctor?
Hayes: I was interested in politics and economics, going back to high school. I knew that even if I became a doctor, my plan was to do an MD/MPH or MD/MPP and get a dual degree that would allow me to maybe do health policy in addition to medicine. Later, I had some shadowing experiences that, while very interesting, made me realize that practicing medicine was probably not something I wanted to do in the long term. At the same time, I was taking more economics classes and specifically had taken a public finance course that laid out ways of looking at health policy issues using concepts from economics. It was around then that I decided I wanted to shift and go to grad school for economics.
And was that how you became interested in socio-economic inequality?
Hayes: I’ve always been interested in socio-economic inequality, in part because of my own family’s story of upward mobility across the past couple of generations, but also because of my experience at an HBCU. I went to Howard University, an HBCU, as an undergrad. I really enjoyed my time there and know that it and other HBCUs are really important for facilitating upward mobility for Black people in the U.S.
However, at Howard, I could sometimes see how differences in economic background often impacted the extent to which students could succeed there. I had classmates who were from middle class to upper middle class backgrounds who seemed to have a relatively easier time within this institution that can facilitate upward mobility, compared to classmates who came from lower-income families. On top of dealing with the stress of classes and extracurriculars, these lower-income students also had to be concerned about whether they would be able to pay tuition that semester and often worked jobs that limited their time for studying or other opportunities. And seeing that made me think about the differences in opportunities that people have, and how even within institutions or programs that are known to help people advance, those who likely stand to benefit the most may also have a harder time navigating them because of the very circumstances that drew them there in first place. That experience generally got me thinking about the policies and institutions here in the U.S. that target inequality and who really benefits from them. And of course my growing interest in health policy and economics coincided with this experience as well.
What projects do you plan to work on during your time as a Stone Center postdoc?
Hayes: I want to keep working on projects that look at childhood health and outcomes over the life cycle. I have some really good data that I used for my dissertation, and I’m trying to see what the potential uses are in terms of thinking about the impacts of childhood health. One of my priorities, especially for this first year, is to expand my job market paper and continue that work of looking at outcomes over the life course, as well as some work that looks at the effects of the measles vaccine. I’ll also be looking at the interaction between childhood health and race and ethnicity, and how these things interact to lead to inequality over the life cycle.
A second area of my work is health insurance and employment. I have a paper with Nicole Maestas and Kathleen Mullen that looks at how health insurance coverage affects employment outcomes for people who experienced the new onset of a disability. In the U.S., health insurance is largely tied to employment. For a lot of people that means that they’re going to try and remain employed even if they want to leave their job, because they fear losing their health insurance. This can be especially true for people with disabilities, as they likely have higher healthcare needs and are really averse to losing their insurance. At the same time, they’re dealing with a disability or health problem that may limit their capacity to continue working in that job or at all. And so we look at that population and their health insurance coverage sources and whether they have some other coverage available to them outside of employment, and how that impacts their labor market outcomes.
Beyond that, I want to start looking at intergenerational mobility and how health plays a role there. I’m really excited to be at the Stone Center and in a community of people who study intergenerational mobility because that will help me see what sort of work can be done in that area and what I can contribute. I’d also like to look at racial wealth inequality in the U.S; that’s another area that I’ve always been interested in, and this is a good place to start exploring it more.
We’re seeing enormous changes in health policy at the federal level. What do you think will be the impacts of the most recent changes, such as reductions in vaccine access and cuts to Medicaid?
Hayes: I have been thinking about this quite a bit. A lot has already been said by those in fields of medicine, public health, and epidemiology about the potential health impacts of reductions in vaccine access. Childhood vaccines have historically been important for reducing childhood morbidity and mortality from various illnesses, and the concern now is that lower rates of vaccination among children could lead to greater rates of illness and death from diseases we previously had under control. With Medicaid cuts, we’ll likely see a substantial increase in the number of uninsured individuals, with people losing critical coverage and facing a greater financial burden from their healthcare. Cuts to Medicaid could also have significant health impacts, not just from reductions in healthcare utilization by those who lose coverage but also from the potential closures of hospitals, which could significantly limit access to life-saving hospital services for everyone in those areas.
I think my work could shed some light on the potential long-term economic effects of any increases in morbidity and mortality that are associated with the new policy landscape, especially among children. Although I also would hesitate to generalize my results to this new generation, who will certainly be growing up in a different world than the cohorts I study.
