In people with diabetes, the insulin-producing beta cells in the pancreas are lost or become dysfunctional, leading to a deficiency or absence of insulin secretion. There are two main types of diabetes: type 1 diabetes and type 2 diabetes, and the reasons for the loss of beta cells differ between these types:
Type 1 Diabetes: Type 1 diabetes is an autoimmune condition where the immune system mistakenly attacks and destroys the beta cells in the pancreas. The exact cause of this autoimmune response is not fully understood, but it is believed to involve a combination of genetic predisposition and environmental triggers, such as viral infections or other environmental factors. As the beta cells are progressively destroyed, the ability to produce insulin decreases, resulting in a severe deficiency of insulin.
Type 2 Diabetes: Type 2 diabetes is characterized by insulin resistance, where the body's cells become less responsive to the effects of insulin. Initially, in type 2 diabetes, the pancreas compensates by producing more insulin to overcome the resistance. However, over time, the beta cells may become exhausted from this increased demand and lose their ability to produce sufficient insulin. As a result, insulin secretion decreases, and blood sugar levels rise.
In both types of diabetes, the loss of insulin-producing beta cells is a significant factor in the development and progression of the disease. In type 1 diabetes, the loss is due to an autoimmune attack, while in type 2 diabetes, it is often a combination of insulin resistance and beta cell dysfunction. Researchers are continually studying the underlying mechanisms to better understand how to prevent or reverse the loss of beta cells and improve diabetes management.