High Fructose Corn Syrup...and your memory

[MJ]

4. High Fructose Diets Impair Memory in Rats

Diets high in fructose, a type of sugar found in most processed foods and beverages, impaired the spatial memory of adult rats, according to researchers at Georgia State University.

Amy Ross, a graduate student in the lab of Marise Parent, associate professor at Georgia State's Neuroscience Institute and Department of Psychology, fed a group of Sprague-Dawley rats a diet in which fructose represented 60 percent of calories ingested during the day.

She placed the rats in a pool of water to test their ability to learn to find a submerged platform that allowed them to get out of the water. She took them back to the pool two days later with no platform to see whether they could remember to swim to the platform's location.

"What we discovered is that the fructose diet doesn't affect their ability to learn," Parent said. "But they can't seem to remember as well where the platform was when you take it away. They swam more randomly than rats fed a control diet."

Fructose, unlike another sugar, glucose, is processed almost solely by the liver. It produces an excessive amount of triglycerides ? fat that get into the bloodstream. Triglycerides can interfere with insulin signaling in the brain, which plays a major role in brain cell survival and plasticity, or the ability of the brain to change based on new experiences.

Results were similar in adolescent rats, but it is unclear whether the effects of high fructose consumption are permanent, she said.

Fructose includes common table sugar and fruit juice concentrates, as well as the much-maligned high fructose corn syrup.

Although humans do not eat fructose in levels as high as the rats in the experiments, the consumption of foods sweetened with fructose has been increasing steadily. High intake of fructose is associated with numerous health problems, including insulin insensitivity, Type 2 diabetes, obesity, and cardiovascular disease.

"The bottom line is that we were meant to have an apple a day as our source of fructose," Parent said. "And now, we have fructose in almost everything."