How does fasting cause hypoglycemia?

It should not: When your pancreas and liver are functioning properly, fasting should not cause hypoglycemia. If fasting causes hypoglycemia in you, you should be seen by your endocrinologist for further evaluation. Frequently we find there wasn't true hypoglycemia and something else was happening.

Sugar regulation : When someone is not eating, sugar is converted from stores in the liver first, then muscle, then fat. When the enzymes or the conversion processes are not effective fast enough or the stores are very low or when their metabolism is very high then the person's sugar goes low . Therefore the actual sugar level is a balance between the last time eaten, enzymes, the stores and metabolism