Is Alzheimer's a Form of Diabetes?:
Scientists have been searching for the cause of Alzheimer’s disease for more than 100 years, and during that time, theories about why brain cells are destroyed in the course of the illness have come and gone. One of the newer and more unorthodox theories posits that Alzheimer’s may actually be a form of diabetes. Some experts have even taken to calling the brain disease type 3 diabetes, as distinct from the insulin-dependent (type 1) and adult-onset (type 2) varieties of the condition.
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The link between the two diseases was first made about a decade ago when scientists found accumulations of insulin in the brains of Alzheimer’s patients. Doctors have long known that patients with diabetes were two to five times more likely to develop the brain-killing illness, but most Alzheimer’s patients are not diabetic. Insulin creation in the brain is a separate process from insulin production elsewhere in the body, says Brown University’s Dr. Suzanne de la Monte. Thus insulin resistance is separate, too.