High Blood Sugar Related to Memory Loss

There are many things that we need to do to protect ourselves as we age. One recent finding is maintaining a normal blood sugar level as we grow older, which may protect against more diseases than diabetes. Normal blood sugar levels could also help prevent age-related memory loss.

The researchers, by using high-resolution brain imaging, showed that blood sugar levels that are on the rise selectively target a key area of the brain that is linked to the decline of memory.  This finding suggests that interventions to help improve blood sugar, such as maintaining regular exercise and a healthy diet, could help with both the brain and the body as it ages. 

The lead researcher, Scott Small, M.D., who is from the Columbia University Medical Center, said, “We have known that exercise improves blood sugar and that it help prevent age-related memory loss. In this study, we were able to show the specific area of the brain that is impacted by rising blood sugar.”

Focusing on the hippocampus, which is the area of our brain associated with learning and memory, Small and his team previously identified a section of the brain that was most associated with age-related memory decline.  In their new study, the researchers looked at how this particular area, known as the dentate gyrus, is affected by changes that are typically seen with aging, such as body weight, rising cholesterol, and blood sugar. Animal and human imaging studies have confirmed that rising blood sugar was the only change that was directly associated with the decreased activity in the dentate gyrus.

Because our blood sugar levels tend to rise as we age, the finding suggests that monitoring and taking steps to lower blood sugar as we get older could be an important strategy for preventing age-related cognitive decline for everyone, not just for people that suffer from diabetes.

Small stated, “Beyond the obvious conclusion that preventing late-life disease would benefit the again hippocampus, our findings suggest that maintaining blood sugar levels, even in the absence of diabetes, could help maintain aspects of cognitive health.”

Linda Nichol, Ph.D., from the National Institute on Aging, said that the research could help explain why people with diabetes are at an increased risk of developing Alzheimer’s disease. She stated that studies are currently underway to determine if drugs that regulate blood sugar can help slow cognitive declines in people that have early evidence of the disease.  It is still far too soon to say if people who do not have diabetes might benefit from taking the medications as they age.  She added, “We already know that physical exercise can help people stay cognitively sharp as they age. This study may help explain why.”