High Blood Sugar Linked to Memory Loss
Taking Steps to Lower Blood Sugar May Protect Against Age-Related Memory Loss
Dec. 30, 2008 -- Maintaining normal blood sugar levels as we age
may protect against more than diabetes. It may also help
prevent age-related memory loss, a new study shows.
Using high-resolution brain imaging, researchers showed that rising blood
sugar levels selectively target a key area of the brain linked to memory
The finding suggests that interventions to improve blood sugar, such as
getting regular exercise and eating a healthy diet, may help both the body and
the brain as it ages.
"We have known that exercise improves blood sugar and that it helps
prevent age-related memory loss," says lead researcher Scott Small, MD, of
Columbia University Medical Center. "In this study, we were able to show
the specific area of the brain that is impacted by rising blood sugar."
Blood Sugar and Memory
Focusing on the hippocampus -- the area of the brain associated with memory
and learning -- Small and colleagues previously identified a section that was
most associated with age-related memory decline.
In their newly published study, the researchers looked at how this area,
known as the dentate gyrus, is affected by changes typically seen with aging,
such as rising cholesterol, body weight, and blood
Human and animal imaging studies confirmed that rising blood sugar was the
only change directly associated with decreased activity in the dentate
Because blood sugar levels tend to rise with age, the finding suggests that
monitoring and taking steps to lower blood sugar as we grow older may be an
important strategy for preventing age-related cognitive decline for everyone,
not just people with diabetes, Small tells WebMD.
The study was funded by the National Institute on Aging, the American
Diabetes Association, and the McKnight Brain Research Foundation. It appears in
the December issue of the journal Annals of Neurology.
"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," Small says in a news release.
Exercise Lowers Blood Sugar
Because exercise improves the ability of the muscles to process glucose, it
makes sense that it helps protect cognitive function as we age, Small says.
Linda Nichol, PhD, of the National Institute on Aging, tells WebMD that the
research may help explain why diabetic people are at increased risk of
developing Alzheimer's disease.
She says studies are under way to determine if drugs that regulate blood sugar
can help slow cognitive declines in people with early evidence of the
It is far too soon to say if people who don't have diabetes might benefit
from taking the drugs as they get older, she says.
"We already know that physical exercise can help people stay cognitively
sharp as they age," she adds. "This study may help explain