New research out of Australia confirms that junk food damages the brain. BBC Medicine reports that a diet high in junk food shrinks your brain and accelerates mental decline.
The hippocampus is the area in the brain responsible for memory and learning. If the hippocampus isn’t functioning properly, neither are our brains. Hunger and satiety cues are disturbed by a damaged hippocampus as well. The most recent study out of Deakin University and Australian National University suggests that junk food may just be damaging the highly sensitive hippocampus.
Older men and women between the ages of 60 and 64 who consumed the most junk food (processed meats, sweet beverages/sodas, and salty snacks) had smaller hippocampi than older men and women who ate healthier food (vegetables, fruits, and fish). These results held even when other factors that might affect the hippocampus, such as gender, activity level, smoking, education, and depression, were controlled for.
Hippocampus size was measured using magnetic resonance imaging (MRI). Researchers also monitored participants’ regular diets, as well as other factors, such as exercise, smoking, etc. Lead author Felice Jacka explains:
“This study sheds light on at least one of the pathways by which eating an unhealthy diet may influence the risk for dementia, cognitive decline, and mental disorders such as depression and anxiety in older people. However, it also points to the importance of diet for brain health in other age groups. As the hippocampus is critical to learning and memory throughout life, as well as being a key part of the brain involved in mental health, this study underscores the importance of good nutrition for children, adolescents, and adults of all ages.”
Other studies substantiate the link between junk food diets and declining brain function. For example, rats fed a high-fat, high-sugar diet performed significantly worse on memory tests than did rats fed normal diets. The rats on the junk food diet had trouble finding objects and couldn’t determine when an object had moved. That’s the equivalent of us trying to find our sunglasses when we’ve put them on top of our heads.
A 2011 study published in the American Journal of Clinical Nutrition showed that healthy individuals who splurged on 5 days of junk foods did much worse on brain tests that measured attention, speed, and mood.
Scientists have not yet pinpointed just how junk food impacts the brain, but inflammation is thought to be a key factor, particularly inflammation in the hippocampus.
Your Brain on Nutritious Food
Swap out the junk food for the healthy eats below.
Walnuts: A Spanish study suggests that a handful of walnuts a day can improve working memory by up to 19%. The polyphenols in walnuts are believed to help enhance communication between neurons (nerve cells).
Fish: Full of omega-3 essential fatty acids, fish has been found to help alleviate inflammation, a key factor in cognitive decline. A study published in the journal Neurology showed that people with the smallest concentration of omega-3s in their brain cells had the smallest brains!
Spinach: Packed with iron, calcium, and magnesium, spinach has been found to help dilate the blood vessels by boosting blood flow throughout the body and brain, according to Japanese researchers.
Healthy Oils: Olive oil and avocado oil are rich in polyphenols and healthy fatty acids that lower inflammation in the joints and cells. Along with coconut oil, they are the best choices for your cooking and baking needs.
Mussels: More than just a delicatessen, mussels boast some of the highest vitamin B12 levels around, and can help protect and insulate brain cells.
Coffee: Need some extra brain-boosting power? A recent British study suggests that just 20-30 milligrams of coffee can help strengthen brainpower.