Spikes in blood sugar levels seem to be linked to memory problems, and may be a major factor in the normal memory and cognitive problems that crop up as people age, according to a new study. People’s ability to regulate blood sugar begins to deteriorate by their third or fourth decade and continues to decline, so older people are more prone to these sugar spikes. “This would suggest that anything to improve regulation of blood glucose would potentially be a way to ameliorate age-related memory decline,” said senior study author Dr. Scott Small…. The findings may also help explain why people who exercise don’t have as many cognitive problems as they age: Exercise helps stabilize blood glucose levels [HealthDay News].
The findings have important implications for the increasing number of overweight children who are at risk of diabetes, commented neuroscientist Bruce McEwen. “When we think about diabetes, we think about heart disease and all the consequences for the rest of the body, but we usually don’t think about the brain,” he said. “This is something we’ve got to be really worried about. We need to think about their ultimate risks not only for cardiovascular disease and metabolic disorders, but also about their cognitive skills, and whether they will be able to keep up with the demands of education and a fast-paced complex society. That’s the part that scares the heck out of me” [The New York Times].
In the study, published in the journal Annals of Neurology [subscription required], researchers gathered 240 healthy volunteers over the age of 65 and conducted fMRI brain scans, blood sugar level tests, and memory assessments. They found that elevated blood glucose levels were correlated with both forgetfulness and reduced blood flow in a part of the brain called the dentate gyrus, a pocket in the hippocampus section of the brain. The hippocampus is involved with learning and memory formation…. The dentate gyrus’s exact function is unknown. But it’s one of several circuits in the hippocampus that, if disrupted, impairs memory, such as a person’s ability to learn the names of new people or to remember where they parked their car [Scientific American].
It’s well known that damage to the hippocampus is evident with Alzheimer’s disease, and there has been some suggestion that this region of the brain is also affected by normal aging [HealthDay News]. The new results, though preliminary, suggest a useful new avenue of research for scientists seeking to reverse memory decay. And while that work will take years, researchers stress that people can easily take cautionary measures in the meantime, as exercise and a healthy diet may both help fend off memory loss.
80beats: Good Cholesterol Linked to Good Memory
Image: flickr / Uwe Hermann