No Junk Science: Study Says Junk Food Makes You Stupid

Amy Schaeffer

Everyone is aware that junk food, including most fast food, is unhealthy, with a disproportionate amount of fat and carbohydrates as compared to what a healthy diet should consist of. Fast food has been implicated in severe chronic health conditions as a contributing factor: obesity, diabetes (Type II), hypertension, insulin resistance, and even sleep disorders like sleep apnea, and mood disorders. Now, however, there is a study that was conducted with rats that showed a substantial mental function decline after eating a diet high in fat and carbohydrates, but low in protein and probiotics, the "good" bacteria your gut needs in order to properly digest and absorb food.

The study was conducted by researchers at Oregon State University and published in the peer-reviewed journal, Neuroscience. While the results were not particularly surprising, one facet did have some new implications -- high-fat, high-sugar diets have negative effect on what they refer to as "cognitive flexibility," or the power to adapt and adjust to changing situations, which may impact emotional behavior, conflict resolution, relationships, and stress.

The design of the study was experimental, using laboratory mice that ate different diets with varying levels of fat and sugar before facing a series of tests — mazes and basic puzzles — to monitor changes in their mental and physical function. The researchers paid specific attention to the types of gut bacteria present in each control group after their specific diets over time. Kathy Magnusson, a professor in the OSU College of Veterinary Medicine and principal investigator with the Linus Pauling Institute, said the results are likely applicable to humans, as well.

"Bacteria can release compounds that act as neurotransmitters, stimulate sensory nerves or the immune system, and affect a wide range of biological functions. We're not sure just what messages are being sent, but we are tracking down the pathways and the effects. This work suggests that fat and sugar are altering your healthy bacterial systems, and that's one of the reasons those foods aren't good for you. It's not just the food that could be influencing your brain, but an interaction between the food and microbial changes."

[Photo by Tech Prone]