A diet in sugar is not just bad for your waistline. High-fructose corn syrup affects how you think, and may be making you dumber.

High-fructose corn syrup not only impacts your physical health but it also affects how you learn and your memory.  While this can be alarming for many individuals who need a quick boost of energy or enjoy a sweet snack, Omega-3 fatty acids can limit some of the damage high-fructose does to your brain.

A new study, led by Fernando Gomez-Pinilla, PhD, from the University of California-Los Angeles, used rats to see how fructose, including high-fructose corn syrup, affects the ability to think and learn. High-fructose corn syrup is a cheap way to sweeten many processed foods, from soft drinks to condiments. High-fructose has been getting plenty of attention of late including recent studies the link the sweetener to diabetes, fatty liver disease and obesity.

For the study, two groups of rats were given fructose as part of their water supply while one group also received Omega-3 fatty acids as part of their diet.  The groups of rats were trained on a maze prior to the diet changes. After six weeks of the diet, the rats were timed and evaluated on how well they remembered the maze.

The rats that did not have the Omega-3 fatty acids as part of their diet had a terrible time trying to recall how to escape the maze. The fructose group of rats was slower than the rats that had omega-3 fatty acids as a supplement and researchers noticed a decline in brain activity in the high-fructose group of rats.

It should be noted that the amount of fructose consumed by the rats on daily basis for the study would be the equivalent of consuming 51 cans of soda in a day for humans.

The Omega-3 fatty acids helped prevent the damage caused by fructose by reinforcing the synapses, which play a role in how the brain learns and memory. Researchers used flax seed oil and docosahexaenoic acid (DHA), which has been shown to protect the synapses from damage, as the sources of Omega-3 fatty acids for the rats.

The fructose-only group of rats showed a resistance to insulin, which helps synaptic response in the brain and regulates blood sugar levels.  Too much fructose may prevent the normal regulation of how the body uses sugar and causes an increased level of insulin. According to Dr. Gomez-Pinilla, insulin may affect learning and memory.

The average American consumes over 35 pounds of high-fructose corn syrup each year according to the United States Department of Agriculture. To help reduce the dumbing effects of sweeteners, Dr. Gomez-Pinilla recommends eating foods high in Omega-3 fatty acids such as salmon, flax seed oil, walnuts or taking a DHA supplement daily. Got a taste for chocolate? Having a bar of dark chocolate that has not been processed with sweeteners won’t hurt your memory.

High-fructose, and other sugary sweeteners, may be doing more to hurt your memory and learning than videogames or any other form of entertainment. The next time you forget an anniversary or important birthday, blame it on that soda you had. 

The study was published in the Journal of Physiology.

 

May 22, 2012 -- Updated to reflect the corrections made by the UCLA after their initial reporting of the study.