Blood sugar linked to cognitive aging

Keeping blood sugar levels under control may help to ward off cognitive decline, new research suggests.

Previous research by Scott A Small, associate professor of neurology at Columbia University Medical Center, and colleagues revealed that decreasing brain function in an area of the hippocampus, called the dentate gyrus, is a major contributor of the memory decline that occurs with aging. In this study, the researchers used high-resolution brain imaging to examine the specific areas of the hippocampus that are affected by diseases such as diabetes and stroke.

Results showed that a decline in activity in the dentate gyrus was associated with elevated blood glucose levels. Thus suggesting that diabetics and non-diabetics alike should strive to keep their blood glucose levels under control as it may help to ward off cognitive decline that is associated with normal aging.

“This is news even for people without diabetes since blood glucose levels tend to rise as we grow older. Whether through physical exercise, diet or drugs, our research suggests that improving glucose metabolism could help some of us avert the cognitive slide that occurs in many of us as we age,” said Dr Small. “Beyond the obvious conclusion that preventing late-life disease would benefit the aging hippocampus, our findings suggest that maintaining blood sugar levels, even in the absence of diabetes, could help maintain aspects of cognitive health. More specifically, our findings predict that any intervention that causes a decrease in blood glucose should increase dentate gyrus function and would therefore be cognitively beneficial,”

Wu W, Brickman AM, Luchsinger J, et al. The brain in the age of old: The hippocampal formation is targeted differentially by diseases of late life. Annals of Neurology. 2008;64:698-706. doi: 10.1002/ana.21557

News release: Researchers Link Blood Sugar to Normal Cognitive Aging. Columbia University Medical Center. December 30th 2008.