How is Glucose produced?
Glucose is produced by breaking down carbohydrates, principally in the small intestine, when we eat a meal containing carbohydrates (such as pasta or bread).

This glucose enters the bloodstream. When fasting our blood glucose is normally about 4.5-5.5 mmol/L but this can rise to 7 mmol/L or above when eating, yet it returns to normal within 2 hours of eating.

How does our body manage this?

Glucose uptake by tissues
Glucose cannot cross cell membranes without using transport proteins. We will mainly consider the glucose transporter protein GLUT 4.