Often a doctor is asked How does insulin work?

Insulin is a hormone secreted from the pancreas which works as a key which helps by unlocking the utilisation of glucose (sugars) from blood.

When a diabetes patient follows a strict DIET it decreases the glucose production in blood so the lesser challenge is given.
When a diabetic patient EXERCISES daily it helps in more affective utilisation of sugars and ultimately better diabetes control

When despite these efforts sugar rises then doctors help through MEDICATION to increase secretion of insulin or give direct INSULIN injections to control the abnormal rise of sugars in blood.