Insulin + glucose
Insulin is a signal that helps the body manage glucose. Muscle and fat cells respond by bringing more glucose transporters to their surface; the liver also changes how it stores and releases glucose.
The pancreas senses a change
After eating, blood glucose can rise. Beta cells in the pancreas make and release insulin in response.
Insulin helps move the fuel
In muscle and fat cells, insulin signalling moves GLUT4 transporters to the cell surface, helping glucose enter. The liver uses different glucose transporters; insulin regulates its glucose production and storage rather than switching on the same GLUT4 pathway.
The response matters
Insulin resistance means these tissues respond less well to insulin. The pancreas may produce more to compensate. A description of this mechanism cannot establish someone’s insulin sensitivity from a meal or how they feel afterward.
References
Source-checked educational draft. Human editorial review pending.
NIH National Institute of Diabetes and Digestive and Kidney DiseasesInsulin Resistance & PrediabetesSource accessed 2026-09-05World Health OrganizationDiabetes fact sheetSource accessed 2026-09-05NIH National Library of MedicinePhysiology, Glucose Transporter Type 4Source accessed 2026-09-05