Dietary Delights: The Many Meanings of “Food is Medicine”

Dr. Marianna Wetherill describes interdisciplinary health science research as "leveraging the perspectives from diverse professions to better understand determinants of well-being for people and populations." As a dietitian and public health practitioner, she values the unique viewpoints that different disciplines can bring when studying any nutrition-related health problem. Wetherill explains, "The way a social worker might strategize to improve food security will likely be different from how an occupational therapist might work to study and solve the problem—integrating these perspectives can facilitate deeper understandings of complex issues that single disciplines are unlikely to solve on their own." This interprofessional awareness is an important focus in her Lifestyle Medicine in Public Health course, offered via live Zoom for Tulsa and Oklahoma City students. The course covers various lifestyle medicine intervention areas—ranging from food to sleep and stress. In addition to being a faculty member in the Department of Health Promotion Sciences, Wetherill also holds a joint appointment in the OU-TU School of Community Medicine, where she co-teaches lifestyle medicine and culinary medicine courses to community medicine and physician assistant students. "These courses are one of the defining features of the School of Community Medicine specialty track," says Wetherill. 

After earning a bachelor's degree in nutritional sciences from the University of Oklahoma Health Sciences Center, Wetherill became a registered dietitian. "I was really intrigued during my studies about the complex nutrition needs of people living with HIV," she says. An internship with RAIN Oklahoma in Oklahoma City helped her learn more about that specific population. After graduation, Wetherill looked for work opportunities in Tulsa that would allow her to specialize in HIV nutrition, but there were none. "There weren't any dietitians serving the HIV community in my area, so I reached out to Tulsa CARES, an HIV social service agency, to offer my services pro bono," says Wetherill. "This allowed me to start seeing people through the organization's food pantry, where I provided nutrition assessment, counseling, and eventually small group nutrition classes." This was when Wetherill became interested in public health. "I quickly realized that supporting people's health and well-being requires much more than just telling them what to eat," she remarks. "Lack of knowledge is not the main barrier for most people." Wetherill recognized that factors in the community, home environment, relationships, and many other dynamics play a part in health. "My training as a dietitian did not prepare me for the kind of intervention work that I wanted to do that included moving beyond the basics of nutrition education. I was able to find exactly what I needed in public health," she says. Wetherill completed a master of public health (MPH) degree in Health Administration and Policy on the OU Tulsa campus and then decided to pursue a Doctor of Philosophy degree in Health Promotion Sciences—driving between the Tulsa and Oklahoma City campuses all while continuing her full-time work with the HIV community. 

Today, Wetherill's research focuses on the health consequences of food insecurity. It often involves a "food is medicine" intervention element to improve the physical or mental well-being of people with limited food resources. Some of her studies have been purely observational, with the goal of documenting the disparity to inform future work. However, most of her research involves a two-phase approach that begins with data collection, followed by creating a solution to the identified problem(s)—all in partnership with the community. For example, Wetherill conducted a nutrition needs assessment of people receiving free meals at Iron Gate Tulsa, Tulsa's largest soup kitchen. She worked with an OU-Tulsa MPH practicum student, Lacey Caywood, to identify the nutrition needs of people affected by homelessness. Wetherill and Caywood then collaborated with another OU-Tulsa MPH alumni, Valarie Carter of the OU Culinary Medicine team, to develop and introduce new menu items (designed to fill key nutritional gaps in the standard menu) at Iron Gate Tulsa. Soup kitchen guests were invited to vote on their favorite items. Wetherill notes that this project didn't include a collection of any nutrition biomarkers or other objective nutrition-related health data, but she says that type of study is very much needed. "People without housing face numerous nutritional risks, yet ironically, there is very little information on the nutritional status of this population; they're a neglected population that often lacks control over their food options, and if you think about the high disease burden in that population—much of it being diet-related—it's a critical group that could benefit from food is medicine interventions," she concludes. 

Wetherill is currently working on a five-year project funded by the National Institute of Diabetes and Digestive and Kidney Diseases called Nutrition to Optimize, Understand, and Restore Insulin Sensitivity in HIV for Oklahoma (NOURISH-OK). The project is being conducted in partnership with Tulsa CARES, and its goal is to examine the relationships between food insecurity, diet and insulin resistance among people living with HIV. The team is in the fourth year of the study and has accomplished the first two of its three research aims. During the first three years, the Aim 1 study enrolled over 400 people who each completed a comprehensive nutrition assessment and a survey on their social determinants of health and provided fasting blood work to test chronic inflammation and insulin resistance levels.

"I think one of the more unique aspects of this study is we are diving fairly deeply into sources of trauma, adversity and resilience," notes Wetherill. "For example, how might adverse childhood experiences, trauma related to HIV diagnosis, or discrimination be related to food insecurity, and what are some resiliency factors (such as social support or self-esteem) that might provide protective effects?" The Aim 2 study is qualitative and was designed to explore significant relationships identified within the first aim, such as linkages between food insecurity and diet. The Aim 3 study will apply findings from Aims 1 and 2 to develop and test a "food is medicine" intervention. "This will be a 12-week intervention where we hope to improve people's food security status and their diet and hopefully also reverse insulin resistance through the foods we provide," says Wetherill. The team is also collaborating with Oklahoma State University on Aim 1 and 3 studies to examine differences in gut microbiome profiles based on diet and food insecurity and whether these differences may be associated with chronic inflammation or insulin resistance levels. "This project has provided the community with a fascinating opportunity to look at the macro and micro of things from both a quantitative and qualitative perspective," comments Wetherill. Students from nursing, social work, medicine, dietetics, and public health have all had the opportunity to participate in data collection and analysis for this project. 

When asked about the challenges of interdisciplinary research, Wetherill initially hesitates. "I think the benefits outweigh the cons," she answers, "but sometimes finding shared language that makes sense to everyone can be difficult." Wetherill stresses the importance of not assuming that one discipline has the same foundational knowledge as another. She also recommends taking time within your team to determine the research problem's collective goal and how each team member defines success in meeting that goal. When asked about the benefits of interdisciplinary research, Wetherill enjoys the diversity it brings. "A bunch of dietitians sitting around a table talking about people's diets can be very boring," she says with a laugh. "It forces you to see things in a way or consider alternative perspectives that maybe you had never even considered before." 

"Interdisciplinary research forces everyone to grow in their ability to view problems more broadly and to listen to other perspectives."

When prompted about why interdisciplinary research is vital to public health and its students, Wetherill stated, "Public health is an interdisciplinary profession, but sometimes we can get trapped in our departments or silos." She enjoys reaching outside the Hudson College of Public Health because it provides new ways to collaborate, offers unique perspectives, and gets other researchers interested in collaborating with public health. She views this as "sharing and bringing people into public health sometimes through the back door." 

As one of the few Hudson College of Public Health faculty members on the Tulsa campus, Wetherill has the opportunity to work with faculty and students beyond the Oklahoma City campus. When asked what it's like to work there, she grins and says that the Tulsa campus is a well-kept secret. "I absolutely love the Tulsa campus because its design and small size promote interprofessional collaboration," she replies. "It's the kind of environment where you have to be open to working with others across multiple programs, schools, and colleges." This allows Wetherill to network with colleagues that she would otherwise rarely see if she were on the Oklahoma City campus. 

"The Tulsa campus encourages you to network across colleges and schools, and the campus atmosphere is very supportive, collegial, and interprofessional."