The dawn phenomenon is a natural rise in blood glucose between the hours of 4:00 a.m. and 8:00 a.m., and it occurs because of hormonal changes in the body.
In the early morning hours, hormonal changes in your body will naturally cause blood glucose to rise. For people who don't have diabetes, the increase in blood glucose is offset by increased insulin production. For people with diabetes, this can be a problem.
There are a couple of things going on that make your glucose rise in the morning.
One of these is insulin resistance—a condition that means your body's muscle and fat cells are unable to use insulin effectively to lower blood glucose.
However, insulin resistance also affects how your liver processes, stores, and releases sugar, particularly at night.
The liver is supposed to release small amounts of glucose when you're not eating. But in type 2 diabetes, the liver dumps more glucose than is needed into the bloodstream, especially at night.
So, while your hormones are causing a natural rise in blood glucose, your liver is releasing even more sugar into your system. And because your insulin resistance prevents your muscle and fat cells from using the sugar, your blood glucose level rises.
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