Rising Blood Sugar in Healthy People Linked to Poor Memory

Researchers have shown for the first time that even small increases in blood sugar are linked to declining memory and shrinkage of a key region in the brain crucial for memory. This study shows that changes in metabolic efficiency, even small changes, set the stage for cognitive decline.

The study evaluated 141 men and women, average age of 63. They were not overweight, suffering from insulin resistance, or diagnosed with type 2 diabetes. In other words, these people compared to many would be considered quite healthy for their age.

The researchers measured fasting blood sugar levels and hemoglobin A1c, which measures how much sugar “sticks” to red blood cells over time and is an excellent test demonstrating the trend of blood sugar management. They also used MRI scans to measure the size and microstructure of the hippocampus, an important brain structure involved with memory. The participants went through a battery of memory tests.

The researchers showed that even small increases in blood sugar or hemoglobin A1c, despite being in the normal range, were linked to poorer memory performance and disturbed structure of the hippocampus.

Yesterday I reported on another groundbreaking study explaining the precise mechanism by which high blood sugar causes damage to the memory function of the brain, a finding highly relevant to overweight, insulin resistance, and type 2 diabetic patients. This new study documents that such adverse changes are happening at even earlier levels of inefficiency of metabolic function.

This science is painting the picture of a sliding scale of function, with optimal blood sugar metabolism at the high end which correlates significantly with better memory. As a person falls away from optimum in terms of blood sugar metabolism then the brain is progressively "punched in the nose" by the problem. Smaller levels of blood sugar problems are smaller punches, but they are still enough to deteriorate the structure of the brain and optimal human performance.

This data demonstrates that every person should work diligently to optimize their body weight and blood sugar metabolism. And one good reason for doing that is to maintain your ability, competitive edge, and quality of mental function as you grow older.