Auriel Willette (right), an assistant professor of food science and human nutrition; and Joseph Webb, a graduate research assistant, found on average that Caucasians with one bad version of guanosine triphosphate cyclohydrolase-1, or the GCH1 gene, developed Parkinson’s symptoms five years earlier, and had a 23 percent increased risk for the disease. Photo by Ryan Riley.

Iowa State uncovers links between obesity and the brain

Auriel Willette is a human scientist who studies the interplay between bodies and brains, uncovering the secret links between physical and cognitive health.

The Iowa State University assistant professor in food science and human nutrition says one-third of the American population is obese. While the physical impact of obesity on physical health is well-documented, Willette is curious about what obesity does to the brain.

“We focus on all these diseases that could kill you, but people tend to think of those as 20 years down the line,” he said. “What I am more interested in is, ‘How is it affecting people now? Is that something that is meaningful and important for brain function? For our ability to think? How we feel?’ The answer is ‘yes.’”

Healthy body, healthy brain

In his study of brain structure and function, Willette’s research focuses specifically on Alzheimer’s disease. He explains that a number of obesity-induced metabolic problems — such as Type 2 diabetes and insulin resistance — may increase risk of Alzheimer’s.

He also looks at the role of genetics in developing the disease. Scientists have linked a gene called TOMM 40 with increased risk of being diagnosed with Alzheimer’s, but the gene may also predispose people to developing diabetes and vascular problems.

“The big part is looking at the contributions of Type 2 diabetes, metabolic syndrome, and insulin resistance and basically how obesity can, over time, really be related to Alzheimer’s.”

As a human scientist, Willette also examines the link between obesity and how the brain perceives and processes stress.

“People in general are fairly stressed in this digital age,” he said. “One thing I’m curious about is why people who are obese have an increased tendency to get stressed out.”

Willette says obesity can lead humans to be more prone to perceiving situations negatively, therefore making them more prone to stress.

“We have some new data that says if you have Type 2 diabetes, your brain is wired in such a way that you focus more on negative things,” he said.

Large scale impacts

Ultimately, Willette wants to curb obesity-induced problems on a societal level. He estimates that 40 to 50 million people will be affected by Alzheimer’s disease by 2050, either as patients or caretakers. This places a large financial responsibility on the economy to cover the costs of care.

Willette predicts that reducing obesity to keep the brain healthy can also help today’s economy.

“All jobs require attention and focus,” he said. “It’s something that can ultimately help people’s bottom line.”

Through Willette’s integrated neuroscience research, he is also grooming another generation of human scientists.

“Our research into the biological and chemical means used to power the brain continues to yield new and potentially significant public health results,” said Kelsey McLimans, a doctoral student and graduate research assistant in nutritional science.  

Joe Webb, a senior in nutritional science and undergraduate research assistant, said the research offers a glimpse of not just the brain, but human life.

“By questioning biological processes, human scientists address the multidimensional problems facing our world today to improve others’ lives,” Webb said.