Insulin is a crucial hormone produced by the beta cells in the pancreas that plays a central role in regulating the body's metabolism and energy use. Its primary function is to help cells absorb glucose (blood sugar) from the bloodstream, allowing the body to use glucose as a source of energy. After you eat, glucose levels in the blood rise, prompting the pancreas to release insulin. Insulin facilitates the uptake of glucose into cells of the liver, muscles, and adipose (fat) tissue, where glucose is either used immediately for energy or stored as glycogen or fat for later use. This process lowers blood glucose levels to a normal range
. Besides glucose regulation, insulin also promotes the metabolism of fats and proteins, contributing further to the body's energy supply. It supports anabolic processes such as glycogenesis (glycogen formation), lipogenesis (fat formation), and protein synthesis, which are essential for growth and tissue repair. Insulin acts as the main anabolic hormone in the body, promoting the storage and building of molecules, while its counterpart hormone glucagon triggers the breakdown of stored energy when blood glucose is low
. When insulin is deficient or the body’s cells become resistant to its effects (insulin resistance), glucose remains in the bloodstream, leading to high blood sugar levels. This condition is associated with diabetes and can cause serious complications if not managed properly
. Insulin also helps prevent excessive fat breakdown by inhibiting hormone- sensitive lipase in adipose tissue
. In summary, insulin's key roles in the body are:
- Regulating blood glucose levels by enabling cellular glucose uptake
- Promoting storage of glucose as glycogen in liver and muscles
- Facilitating fat and protein metabolism for energy and tissue repair
- Acting as a major anabolic hormone supporting growth and storage processes
- Maintaining overall energy balance and metabolic homeostasis
