It's long been understood that there is a connection between memory problems and diabetes, a disorder characterized by excessively high blood sugar. Sugar provides the body with fuel for various processes, including memory processing. In fact, glucose carried in the blood stream supplies the brain with ninety percent of the energy it requires to function properly.
In order to fuel those processes, glucose has to get from the blood to the tissues, where it can be broken down and put to work. High blood sugar levels, such as in diabetes, are an indicator that a body is experiencing difficulty moving sugar from the blood to the tissues.
However, some non-diabetics have a less severe form of high blood sugar, a condition called impaired glucose tolerance. It is this condition that seems to be the cause of memory problems in a significant number of non-diabetic elderly people who experience memory difficulties.
Subjects were given glucose intravenously; then, researchers measured how quickly glucose moved from the blood to the tissues. Next the subjects were tested for overall cognitive functioning and the ability to recall short paragraphs. The results? Subjects who scored lowest on memory recall tests also showed impaired glucose tolerance.
In addition, brain scans demonstrated that these same subjects each had a significantly smaller hippocampus, a brain area important to learning and memory. The researchers hypothesize that impaired glucose tolerance may, over time, cause damage and atrophy to the hippocampus.
What can a body do to prevent this? A healthy diet and exercise can help maintain good glucose tolerance, perhaps preventing gradual memory decline.