What is GLP-1?

The discovery of GLP-1 represents a milestone in understanding how the human body regulates metabolism and energy balance. This peptide hormone belongs to a family of incretin hormones that are secreted by specialized cells in the small intestine, particularly the L-cells located in the ileum and colon, in response to food intake. When you eat, these cells release GLP-1 into the bloodstream, triggering a cascade of metabolic responses designed to optimize nutrient processing and maintain stable blood glucose levels. The hormone's effects extend far beyond simple sugar regulation, influencing appetite centers in the brain, slowing gastric emptying, and promoting a feeling of fullness that naturally reduces caloric intake.

Understanding what GLP-1s are in the context of natural physiology helps explain why synthetic versions have become so effective as therapeutic agents. The body's natural GLP-1 has a very short half-life of only a few minutes, as it is rapidly broken down by an enzyme called dipeptidyl peptidase-4 (DPP-4), which is why pharmaceutical companies developed longer-lasting synthetic versions to provide sustained therapeutic benefits throughout the day.