Healthy diets link to enhanced cognitive flexibility: Study

Adults at risk of late-onset Alzheimer's disease who ingest more omega-3 fatty acids perform better in cognitive flexibility tests and have bigger anterior cingulate cortices, according to a new study conducted at the University of Illinois-Champaign.

The anterior cingulate cortex is a small part of the prefrontal cortex in the brain and controls the ability to switch between tasks efficiently.

Doctoral student Marta Zamroziewicz worked with Aron Barbey, director of the Decision Neuroscience Laboratory at the Beckman Institute for Advanced Science and Technology at the University of Illinois to examine the relationship between biomarkers of diet and brain health. They analyzed 40 healthy adults between the ages of 65 and 75 who carry the gene that may lead to the risk of developing late-onset Alzheimer's disease.

By taking blood samples and measuring the levels of EPA and DHA (two omega-3 fatty acids found in fish) and taking MRIs of their brain, the researchers concluded those who consume more of these acids had enhanced cognitive flexibility because their anterior cingulate cortex was bigger.

Recent research suggests that cognitive impairment and degenerative neurological disorders, such as Alzheimer's disease, are linked to deficiencies in diet, Barbey said in a release. However, they were the first to connect that healthy eating habits can preserve cognitive function, slow the process of aging and reduce the risk of developing diseases, Zamroziewicz said.

“The motivation for this study is that there is evidence to show that omega-3 benefit specific regions of the brain, specifically the prefrontal cortex, and they are important for executive functions in cognitive flexibility,” Zamroziewicz said. “It makes sense, but it is exciting that we were the first to do it in one analysis.”