14 DAY TRIAL // A new research at the University of Texas at Austin concluded that insulin sensitivity could be the link between obesity and memory problems.
Obese individuals have insulin sensitivity impairment and because of this, they have different brain responses than normal-weight people do, while completing cognitive tasks.
Previous studies have shown that midlife obesity is linked to risk of cognitive decline and dementia in old age, so the researchers carried out and experiment, to better understand the reasons behind this phenomenon.
They carried out functional magnetic resonance imaging on middle-aged adults, between 40 and 60 years of age while they were completing a difficult cognitive task.
All participants, normal-weight, overweight and obese, performed equally well on the task, except that the scientists noticed a lower functional brain response in the inferior parietal lobe, in obese individuals.
Also, obese participants had lower insulin sensitivity than others, which means that their bodies break down glucose less efficiently, and this could lead to diabetes mellitus later on, if the pancreas cannot secrete enough insulin to compensate for the low use of glucose.
These results strengthen the belief that a healthy lifestyle at midlife leads to a higher quality of life later on, and this is rather important, as the life expectancy is rising, thanks to new drugs and technologies.
Insulin sensitivity was studied in this case because it is what helps people regulate their metabolism and it also affects cognitive functions.
Psychology graduate student Mitzi Gonzales, co-author of the paper along with Assistant Professor Andreana Haley and other colleagues, said that “the good thing about insulin sensitivity is that it's very modifiable through diet and exercise.”
“Generally, very few people study the middle-aged segment of the population, but that's when many chronic diseases are first identified and neurodegenerative processes are triggered,” added Haley.
“We found that while behavioral performance of obese middle-aged individuals may be the same — they can complete the same cognitive tasks as normal weight individuals — their brain is already doing something different to produce that outcome.”
The two researchers – Haley and Gonzales, plan to carry out a follow-up study to see if a 12-week exercise intervention can ameliorate the differences in brain response.
This research was published in the journal Obesity.