A diet high in processed sugar slows the brain, hampering memory and learning while regular consumption of food rich in omega-3s may boost brain function.
“Our findings illustrate that what you eat affects how you think,” study author Fernando Gomez-Pinilla, a professor of neurosurgery at UCLA (University of California, Los Angeles). “Eating a high-fructose diet over the long term alters your brain's ability to learn and remember information.”
During the six week study, the researchers gave two groups of rats either with a fructose solution as drinking water or the fructose solution plus omega-3 fatty acids.
The studied animals were fed standard rat chow and trained on a maze twice daily for five days before starting the experimental diet.
After six weeks, the rats which received omega-3 fatty acids were faster in recalling the route and escaping the maze compared to peers that only consumed high sugar every day.
“The (omega-3 deprived) animals were slower, and their brains showed a decline in synaptic activity," Gomez-Pinilla added. “Their brain cells had trouble signaling each other, disrupting the rats' ability to think clearly and recall the route they'd learned six weeks earlier.”
The rats that only consumed high levels of the sugary fluid also developed signs of insulin resistance, the hormone that controls blood sugar and affects brain function, the scientists reported in the Journal of Physiology.
The scientists suggest that sugar disrupts insulin's ability to regulate how cells use and store sugar, which is the energy source of brain cells. The condition may trigger reactions that disrupt learning and cause memory loss.
The findings suggest that while a high sugar diet including fizzy drinks and sweet food harms the brain as well as other organs, consuming omega-3 fatty acids regularly may reduce sugar’s harmful effects on the brain.