June 24, 2012 at 9:55 AM ET
By Madeline Haller
Prepping for a big presentation but can't seem to remember any of the content? Blame your sweet tooth.
A diet high in sugar may hamper your memory and ability to learn, says a study published in the Journal of Physiology.
Researchers had two groups of rats drink water mixed with fructose, a type of sugar. One of the groups also received omega-3 fatty acids as a part of their diet. After 6 weeks, the rats who drank only sugar water completed a maze slower than the omega-3-fed mice. (We know you're not a mouse -- but you can still take steps to navigate the maze of life. Check out these 27 Ways to Power Up Your Brain.)
Not only were they slower in the maze, the rats who drank only sugar water had higher triglyceride, glucose, and insulin levels. It appears that they entered a state of insulin resistance, which is where the hormone insulin becomes less effective at lowering your blood sugar, says Fernando Gomez-Pinilla, Ph.D., lead study author and a professor of neurosurgery at the David Geffen School of Medicine at UCLA.
Why did sugar wreak havoc on their system?
Here's how it works: Insulin, in addition to controlling blood sugar, also influences the ways in which your brain cells operate. And within the hippocampus -- the part of the brain responsible for short-term and long-term memory -- insulin signaling actually facilitates memory. Therefore, an insulin resistance may be what's causing a disruption in the rats' ability to recall the route they'd learned 6 weeks ago, the researchers hypothesize.
But the good news is, omega-3 fatty acids appeared to have protective effect on the brain.
How so? Although the researchers are unaware of what's happening on a molecular level in the brain, Gomez-Pinilla says it may have to do with the large amount of DHA (the type of omega-3 fatty acid they monitored in the study) that's already present in the brain.
So could sugar slow down your brain, too? The researchers say yes. But since the study monitored the rats for nearly two months, the effect on humans would take several years of exposure to fructose to see these effects. (If you're looking to wean yourself off of sugar, check out these 9 Sneaky Ways to Eat Less.)
Want to reap those protective effects? Pick up a fish oil pil l-- such as Life Extension Super Omega-3 or Vitamin Shoppe Meg-3 Fish Oil EPA-DHA -- both of which come with at least 500 milligrams of omega-3s per soft gel.