Food as a Risk Factor and Treatment for Depression with Ashley Gearhardt, Ph.D.

For more than a decade, Ashley Gearhardt, Ph.D., has been investigating how certain foods can trigger an addictive process. Through her research, Gearhardt has seen the negative impacts of ultra-processed foods (UPFs) on our American diet as well as our mental health. Not only are these foods detrimental to our physical health, UFPs have even become a means of self-medication against low-mood. 

Dr. Ashley Gearhardt
Ashley Gearhardt, Ph.D. 

In the summer of 2022, Gearhardt and her research team began to process data from a pilot study that monitored participant’s physical and behavioral responses when moving from a high intake of UPFs to a diet of nutrient-rich foods. The findings transformed Gearhardt’s previous assumptions about people’s relationship with UPFs.
“For those who were irritable and depressed, I thought they would be showing signs of withdrawal. Instead, they said to have food delivery, and to have their blood sugar, protein, and fiber optimized, meant they felt nourished for the first time,” said Gearhardt. “When a study turns out differently than you expected–that’s when you can get your most interesting ideas.”
This work urged Gearhardt to explore other recent studies and new approaches like nutritional psychology. She couldn’t shake the idea that by making healthy food more convenient for people experiencing depression we could advance our understanding of the illness while also uncovering more effective treatments. 

“I was so passionate. I would talk about it to anyone who would listen. But I wasn’t motivated to turn it into a research project. The lag between idea, funding application, review and decisions can really slow down science,” said Gearhardt.

“When I heard about the groundbreaking approaches that the Eisenberg Family Depression Center was taking to fast track change, I took note.”

Eliminating Barriers to Launching Novel Research Programs

In June 2022, Gearhardt began to assemble an interdisciplinary team, including Joyce Lee, M.D., M.P.H. and Kendrin Sonneville, Sc.D., R.D., to help turn these new ideas into an application for the Depression Center’s inaugural Psych Tank Funding Competition. Housed in the Center’s new Research Innovation Core, Psych Tank invites U-M researchers to pitch innovative ideas for a chance to receive immediate funding. Gearhardt saw this as a surefire opportunity to get her research idea off the ground. 

Fellow panelists applauding for Dr. Ashley Gearhardt after winning the 2022 Psych Tank Funding Competition
Fellow panelists applauding after Dr. Gearhardt won the 2022 Psych Tank Funding Competition

After Gearhardt presented the team’s research proposal during the live event, the team received $150,000 as the first-place winner of Psych Tank’s Breakthrough Awards

Watch Dr. Gearhardt's winning Psych Tank presentation

Ultra-processed Food as Risk Factor for Depression

High levels of UPF intake is associated with a 33% increased risk of developing depression and a greater likelihood of recurrent depressive episodes. With the help of Psych Tank funding, Geardhart’s team aims to use an ecological momentary assessment in individuals with moderate-to-severe depression to uncover how UPF intake may lead to a vicious cycle of worsening depression, which in turn motivates greater UPF intake.

With guidance from the Depression Center’s Mobile Technologies Core, the study aims to measure several important risk factors in individuals experiencing moderate to severe depression, including glucose levels and sleep in participants using cutting-edge technologies. The study also aims to track UPF intake and depression symptoms. Combining objective, real-time data collected with mobile technologies with qualitative inputs will help paint a comprehensive picture of the impacts UFPs have on mental health outcomes. 

“We’re excited to utilize all the services of the Depression Center,” said Gearhardt “The Mobile Technology Core will help us understand how to gather complex data and the Data & Design Core will help us examine it in the most effective way possible.”

Healthy Food as a Low-cost Treatment

Emerging science finds that shifting eating habits away from UPFs to diets composed of minimally processed foods (e.g., fruits, vegetables, lean meat) leads to clinically significant improvements for individuals with moderate-to-severe depression. By securing industry partnerships, Gearhardt’s team aims to employ a healthy meal kit delivery service to test this as an innovative and scalable intervention to reduce depression. 

“I really feel like the convenience factor is what keeps people eating these highly processed foods,” said Gearhardt. “I'm a big fan of setting up programs or structures that make it as easy as possible for people to adopt practices that are healthy for them. We have billion-dollar industries that are already doing this, so we don't have to start from scratch. I know the Research Innovation Core services will be so helpful with that.” 

Gearhardt also believes that the work is particularly relevant in the context of health disparities, as UPFs are often one of the only sources of calories in under-resourced communities of color and for individuals with food insecurity. Thus, unequal exposure to UPFs may be a social justice issue contributing to increased risk of depression in these populations.

Feeling inspired? Gearhardt is one of nearly 200 Eisenberg Family Depression Center members who are actively accelerating depression and bipolar disorder research at the University of Michigan. U-M faculty and learners interested in becoming a member can learn more and apply today.

Stay tuned for updates on Gearhardt’s research and “food as medicine” approach to the treatment of depression. Join our mailing list to learn more about the incredible research to come from our Psych Tank funding competition winners.