Does what we eat affect how we think and process information? Does too much sugar make us stupid? Research undertaken at the University of California – Los Angeles (UCLA
) suggests as much when it looked at rats fed large quantities of high-fructose corn syrup.
According to National Geographic
, in the experiment two groups of rats were fed a fructose solution as drinking water for six weeks. One group only received the sugary solution whereas a second group also received flaxseed oil and omega-3 fatty acids (which function to protect against damage to the nerve synapses and is said to help with learning and memory). In addition to the liquids, the rats eat standard rat food.
As the study progressed, the rats were given exercises to complete. This involved completing a maze. The rats entered the maze twice per day for five days leading up to the new diet and then were tested after the diet.
The researchers found that the second group of rats navigated the maze much faster than the rats that did not receive omega-3 fatty acids. The rats which only received the corn syrup were slower and they also frequently forgot the route through the maze.
The lead researcher, Gomez-Pinilla, speculates that the rats developed resistance to insulin due to the fructose. The scientist was quoted on CBS News
“Our findings illustrate that what you eat affects how you think. Eating a high-fructose diet over the long term alters your brain's ability to learn and remember information. But adding omega-3 fatty acids to your meals can help minimize the damage.”
High-fructose corn syrup is an inexpensive liquid six times sweeter than cane sugar and often added to processed foods and soft drinks. According to the LA Times
this is not the first time that fructose has been associated with adverse health effects. Rodent studies have found that the sugar contributes to obesity.
The research findings were published
in the Journal of Physiology:
R. Agrawal and F. Gomez-Pinilla. 'Metabolic syndrome' in the brain: deficiency in omega-3 fatty acid exacerbates dysfunctions in insulin receptor signalling and cognition. The Journal of Physiology, 2012; 590 (10): 2485