Studies have demonstrated that there is a direct correlation between changes in size of the brains memory center, the hippocampus, and declining memory function. So it’s obviously in our great interest to do everything we possibly can to preserve the size of hippocampus, which is to say, prevent hippocampal atrophy.
It has become clear that there is a powerful direct relationship between not only fasting blood sugar, but even average blood sugar, in terms of predicting the rate at which the hippocampus will shrink and therefore memory will decline. In a new report, recently published in the journal Neurology, researchers in Germany evaluated a group of 141 individuals, average age 63 years, with memory testing as well as a specific type of MRI scan of the brain to measure the size of the hippocampus in each participant. At the same time they looked at blood sugar levels as well as average blood sugar, by assessing a blood test called hemoglobin A1 c.
What these researchers discovered was really quite profound. There was a perfect correlation between having lower blood sugar as well as lower average blood sugar as measured by an A1c test and several markers of brain function. As the authors stated “lower A1c and glucose levels were significantly associated with better scores in delayed recall, learning ability, and memory consolidation.”
They found that the average blood sugar, the A1c “strongly associated with memory performance.” The authors also were able to draw a conclusion between blood sugar and reduction in size of the hippocampus.
The conclusion of the research stated “our results indicate that even in the absence of manifest type II diabetes mellitus or impaired glucose tolerance, chronically higher blood glucose levels exert a negative influence on cognition, possibly mediated by structural changes in learning–relevant brain areas. Therefore, strategies aimed at lowering glucose levels even in the normal range may beneficially influence cognition in the older population, a hypothesis to be examined in future interventional trials.”
Why prevention matters: Brain shrinkage difficult to reverse
A clear relationship has now been detected between blood sugar levels and the expected rate of brain shrinkage that can lead to memory decline and a reduction in overall brain health.
These results are particularly important for the aging population, as at this time there are no known medications that can reverse brain shrinkage. However, the findings should also serve as motivation for everyone regardless of age to keep their blood glucose levels within a healthy range.
The take-home message is to cut the carbs, ditch the sugar, and welcome healthful fats back to the table.