There is a recent emergence in scientific research regarding an association between insulin and Alzheimer’s disease: it has been termed Type 3 Diabetes (Ahmed, Mahmood, & Zahid, 2015). Alzheimer’s disease is a progressive neurodegenerative disorder that is age-related and characterized by intracellular neurofibrillary tangles (NFT) and amyloid-beta plaques. Common findings in the brains of afflicted individuals show impairments of energy metabolism and glucose utilization, as well as insulin receptor, insulin, and IGF deficiency (Ahmed et al., 2015).
Insulin plays a role in regulating energy homeostasis in the hypothalamus, and insulin receptors are widely distributed throughout the brain, especially in the hippocampus, amygdala, and septum (Ahmed et al., 2015). The hippocampus, of note, regulates acquisition and consolidation of memory, and there may be a role of insulin in potentiating memory. Non-diabetic Alzheimer’s patients have manifested increased levels of peripheral insulin resistance biomarkers in their hippocampi. A potential mechanism suggested is that progressive insulin resistance in the brain may increase expression of cerebral inflammatory mediators leading to oxidative stress and mitochondrial dysfunction and a self-propagating cycle of neurotoxicity from oxidative stress and amyloid-beta deposits.
Growing evidence associating Alzheimer’s disease with insulin resistance further highlights the importance of maintaining a healthy body weight and not consuming excessive amounts of sugars and fats in our diets.
To learn more about insulin check out my article: Be More Sensitive…To Insulin!
Ahmed, S., Mahmood, Z., & Zahid, S. (2015). Linking insulin with Alzheimer’s disease: Emergence as type III diabetes. Neurological Sciences, 36, 1763-1769.