The other day my wife and I were trying to remember what we had for dinner the night before at a local Chicago restaurant. According to a new study, our rich dessert might be to blame for this temporary memory loss.
The new study showed that spikes in blood sugar affect the dentate gyrus, which is the area of the brain that helps form memories. Researchers found that effects can be seen even when levels of blood sugar or glucose are only moderately elevated. This study could be provide a reason for declining cognitive abilities because glucose regulation worsens with advanced aging.
According to Dr. Scott A. Small, the lead investigator on the study, “If we conclude this is underlying normal age-related cognitive decline, then it affects all of us.” Typically the body’s ability to adjust glucose begins to decline by the third or fourth decade of life. However, the degree of decline can be improved with physical exercise, which tends to improve glucose regulation. According to Dr. Scott physical exercise can then be seen as a behavioral recommendation.
In order to study memory processes in elderly subjects the researches used high-resolution functional magnetic resonance imaging (MRI) to map brain regions. They found a correlation between elevated blood glucose levels and reduced cerebral blood volume, or blood flow, in the dentate gyrus. This finding indicated reduced metabolic activity and function in that region of the brain. Furthermore, by manipulating blood sugar levels in mice and monkeys, researchers have found a relationship between the glucose spikes and the reduced blood volume.
But this study doesn’t only have implications for elderly and aging patients, but also is relevant for the growing number of obese children and teenagers who are at risk for developing Type 2 diabetes. Because of the association between glucose levels and cognitive skills, those who are overweight now not only run the risk of developing cardiovascular disease and metabolic disorders, but also of decreasing their cognitive skills.
The new study results are collaborated by prior medical research that shows that physical activity can reduce the risk of cognitive decline. There are also medical studies that show that diabetes increases the risk of dementia, or that there is a possible link between Type 2 diabetes and dysfunction in the dentate gyrus.
What is unique and interesting about the current study is that the careful use of MRI scans to map the participants brain activity has yielded a greater understanding of the specific brain regions that are most effected by increases in glucose levels. The hope is that by gaining a more detailed understanding of the problem further advances can be made for those with diabetes or poor diet.