Hack Your Hormones: How Insulin Impacts Brain Function, Mood, and Metabolism
What is insulin? When many of us think of the hormone insulin, we may think of its role in disorders, such as diabetes, and weight gain or loss. Did you know that insulin can also influence cognitive impairments and neuropsychiatric dysfunction? In addition to its role in the peripheral nervous system, insulin can impact a variety of functions in the central nervous system (CNS) which is made up of the brain and spinal cord.
Insulin in Action: After consuming food, beverages, etc., blood sugar (glucose) levels increase and signal insulin release from the pancreas. Insulin then crosses the blood-brain barrier and influences brain regions, like the hypothalamus, to modulate energy levels and other processes. Through expression of insulin receptors in the hypothalamus, insulin regulates peripheral glucose and metabolic homeostasis. Insulin also plays a role in non-metabolic functions, like neuroprotection, memory potentiation, synaptic plasticity, selective attention, and anti-inflammation.
Insulin Resistance: Insulin sensitivity can be altered by a variety of factors, including diet, exercise, aging, and genetic predisposition. In metabolic disorders like prediabetes, diabetes, and obesity, cells can become less responsive to insulin thus causing insulin resistance. These disorders not only involved in weight, heart disease, and blood pressure, but also can increase risk of neuropsychiatric disorders, such as depression.
Sources:
Erichsen, J. M., Fadel, J. R., & Reagan, L. P. (2022). Peripheral versus central insulin and leptin resistance: role in metabolic disorders, cognition, and neuropsychiatric diseases. Neuropharmacology, 203. https://doi.org/10.1016/j.neuropharm.2021.108877
