It has been shown that obesity puts a physical strain on the bodybut new research suggests that being overweight can also cause mental fatigueaccording to a study by researchers at Edwardsville University of Southern Illinois (United States) published in ‘The FASEB Journal’.
The obesity can increase the risk of high blood sugar (glucose), which can develop into type 2 diabetes and other metabolic disorders if left untreated. Impaired exercise capacity or physical stamina can also be a problem for people who are overweight. However, compromised cognitive function has not been as strongly associated with obesity as physical limitations.
The researchers set out to learn more about the onset of obesity and its impact on physical and mental abilities by studying two groups of rats. One group was fed a high-fat diet, and the other a standard diet for six weeks.. The research team measured the rats’ weight, blood glucose and ketone levels twice a week.
The Ketones are chemicals produced by the liver when there is not enough insulin in the body to convert glucose into energy. In the fifth week, the researchers administered an open field test, which measures speed and distance as the animals move through a maze in a given time frame and determines physical exhaustion. A novel object recognition test, which measures mental exhaustion by analyzing the time rats spend examining new and familiar objects, was administered in the final week of the trial.
Both groups of rats gained weight during the trial, but the high-fat diet group, not surprisingly, gained more than the control group. Blood glucose levels fluctuated more in the high-fat diet group as well.. There were no significant differences in mean glucose or ketone levels between the two groups.
He high-fat diet group performed poorly on the novelty recognition test compared to the control group. “Although we were not totally surprised by this finding, this is the first study, to our knowledge, to report mental exhaustion in obese rats induced by a high-fat diet,” said Chaya Gopalan, lead researcher on the paper.