Understanding how insulin resistance affects the brain is crucial for grasping the link between metabolic disorders and cognitive health. Insulin resistance, often associated with type 2 diabetes and obesity, occurs when the body’s cells do not respond effectively to insulin, a hormone that regulates blood sugar levels. This condition not only affects the body’s ability to manage glucose but also has profound effects on the brain.
### Insulin’s Role in the Brain
Insulin plays a significant role in the brain, influencing appetite, metabolism, and cognitive functions. Normally, insulin helps regulate eating behavior by signaling satiety, or fullness, and it supports healthy brain metabolism. However, when insulin resistance develops, these processes can be disrupted. Insulin resistance in the brain is linked to cognitive dysfunction and an increased risk of neurodegenerative diseases like Alzheimer’s.
### Effects of Insulin Resistance on the Brain
Insulin resistance can lead to several adverse effects on the brain:
1. **Cerebral Hypometabolism**: Insulin resistance is associated with reduced glucose uptake in the brain, a condition known as cerebral hypometabolism. This reduction in glucose metabolism is particularly pronounced in areas of the brain linked to Alzheimer’s disease, such as the frontal cortex, parietotemporal cortex, posterior cingulate cortex, and precuneus cortex[1].
2. **Neuronal Damage and Neuroinflammation**: Insulin resistance contributes to neuronal damage and neuroin
