What characteristic defines type 1 diabetes?

Type 1 diabetes is primarily characterized by the immune system's attack on the pancreatic beta cells, which are responsible for producing insulin. This autoimmune response results in insufficient insulin production, leading to high blood glucose levels. Understanding this process is crucial, as insulin plays a vital role in regulating blood sugar levels by facilitating the uptake of glucose into cells for energy.

This distinction is critical since it underscores the importance of insulin in metabolism and highlights the reasons individuals with type 1 diabetes often need to administer insulin externally to manage their blood sugar. Unlike type 2 diabetes, where insulin production may be adequate but the body's cells become resistant to its effects, in type 1 diabetes, the destruction of insulin-producing cells directly impacts the body’s ability to regulate glucose levels effectively.