Brain function

Weight Loss and Brain Function
The Two are Related In Ways
One May Not Imagine

 By Rob Poulos..

Resisting high calorie foods is often difficult, especially for those
who are obese and trying to lose weight. This is no longer believed
to be a lack of willpower either. New research shows that diets high
in refined sugars and saturated fats may actually lead to changes in
the brains of those who are obese.

Terry Davidson, director of American University’s Center for Behavioral Neuroscience, explains that these changes may lead to overconsumption of those foods high in saturated fats and refined sugars, making weight loss more challenging. This becomes a vicious cycle and one that is very difficult to break.

Mr. Davidson’s research, “The Effects of a High-Energy Diet on Hippocampal-Dependent Discrimination Performance and Blood-Brain Barrier Integrity Differ for Diet-Induced Obese and Diet-Resistant Rats” was recently published in the Physiology & Behavior journal. This research focuses on the hippocampus which is the portion of the brain responsible for learning and memory.

During the study, rats which had been trained were given limited accessed to low-fat foods on two problems. One problem tested memory abilities and hippocampal-dependent learning in the rats while the other didn’t. Upon completion of the training portion, the rats were divided into two groups. One had access to the low-fat foods while the other group was given access to high-fat, high-calorie foods.

The high-fat,high calorie foods provided for the rats included certain plant-based fats, including those found in coconut and cottonseed oil, and animal fats, including meats and cheese. These foods, high in saturated fat, are believed to be the unhealthiest of all dietary fats. Previous research has shown that these types of fats are linked to certain cancers as well as cardiovascular disease.

Both groups were then given the same problems. The rats who had eaten the high-calorie, high-fat diet were obese and didn’t perform as well as the non-obese rats who were given the low-fat foods when it came to the hippocampal-dependent portion of the test. For the second problem, both groups tested the same.

Upon completion of the tests, blood-brain barriers of rats in both groups were examined. This blood-brain barrier determines what enters the brain and what does not. The obese rats had impaired blood-brain barriers while the non-obese rats did not. This was demonstrated with the use of dye.

One thing which surprised researchers was the fat that non-obese rats, no matter which food group they were given to eat, tended to eat less of the high-calorie, high fat diet even when given access to it. Some just appeared to have less of a preference for foods of this type. Researchers believe there is a connection. Whatever it is that allows the non-obese rats to eat less and maintain a healthy weight also helps their brains stay healthy cognitively.

The hippocampus suppresses memories. If these findings are true for humans, the hippocampus in those who eat lots of refined sugars and saturated fats may not be able to suppress unwanted thoughts concerning foods. Davidson believes this is a vicious cycle of cognitive decline and obesity. This study backs up previous research in these areas, although the link between the two has yet to be figured out.

Those who are obese can drop the weight and keep it off. Al Roker is a good example of this. This is a lifelong battle though, one that requires permanent changes in the dieter’s lifestyle. Losing the weight also doesn’t mean that the hippocampus goes back to normal. Hippocampal activity remains weaker for life which may explain why some spend their entire life fighting the battle of the bulge.