The Crucial Link Between Insulin and Alzheimer’s: A Type 3 Diabetes?:

A study I posted last year estimated patients who suffer from diabetes may increase their chances of developing Alzheimer’s disease by 65 percent. A revolutionary discovery may go far in explaining the long-suspected link between the two.

Based on post-mortem research on Alzheimer’s patients, researchers found insulin and its related proteins are also produced in the brain and, as such, lower levels of both are likely connected to Alzheimer’s. Insulin and its growth factors, or lack of them, contribute to Alzheimer’s, raising the chance for a Type 3 diabetes, according to the lead researcher.

Scientists found a drop in insulin production in the brain contributes to the degeneration of brain cells, an early symptom of Alzheimer’s. Instead of corresponding to Type 1 or 2 diabetes attributes, this newly identified condition reflects a more complex process originating in the central nervous system, researchers said. Through studying a genetic abnormality in rats that blocks insulin signals in the brain, scientists discovered insulin and IGF I and II were expressed in neurons located in several locations in the brain.

How does this translate into Alzheimer’s?

After examining brain tissue from deceased Alzheimer’s patients, researchers found growth factors are not produced at normal levels in the hippocampus, the sector of the brain responsible for memory. Their absence will cause other cells in the brain to die. Moreover, insulin and IGF I were greatly reduced in areas affected by Alzheimer’s progression: The frontal cortex, hippocampus and hypothalamus. (That same drop in insulin and IGF I wasn’t found in the cerebellum, an area of the brain not affected by Alzheimer’s, however.)

Just another reason, experts are calling this great increase in Alzheimer’s patients a “looming public health disaster” that could potentially turn into an unmanageable health care crisis as baby boomers age. But there are several things you can do to reduce your risks safely, healthfully and inexpensively:

Journal of Alzheimer’s Disease, Volume 7, Number 1, February 2005, pages 45-61

EurekAlert March 7, 2005