As Type 2 Diabetes Develops
During the years when type 2 diabetes slowly develops (which may be up to 10 years through developing metabolic syndrome and continuing on to prediabetes), hormonal control of blood glucose breaks down. To understand how your body responds, it's important to understand the essential hormones involved in blood glucose control.
Four hormones are involved in blood glucose control:
Insulin, made in the beta cells of the pancreas, helps the body use glucose from food by enabling glucose to move into the body's cells for energy. People with type 2 diabetes have slowly dwindling insulin reserves.
Amylin, secreted from the beta cells, slows the release of glucose into the bloodstream after eating by slowing stomach-emptying and increasing the feeling of fullness. People with type 1 and type 2 diabetes are amylin-deficient.
Incretins, hormones secreted from the intestines that include glucagon-like peptide 1 (GLP-1), enhance the body's release of insulin after eating. This in turn slows stomach-emptying, promotes fullness, delays the release of glucose into the bloodstream, and prevents the pancreas from releasing glucagon, putting less glucose into the blood.
Glucagon, made in the alpha cells of the pancreas, breaks down glucose stored in the liver and muscles and releases it to provide energy when glucose from food isn't available
Out-of-Control Blood Sugar During Sleep
For people in the early years of type 2 diabetes, the hormones that control blood sugar can particularly go awry. Here's what happens during sleep to a person with type 2 diabetes:
"Overnight, the liver and muscles get the message from excess glucagon to ramp up the glucose supply because the person is sleeping, not eating," says Marty Irons, R.Ph., CDE. "There is not enough GLP-1, insulin, or amylin hormones to stem the tide of excess glucose from the liver and muscles, essentially throwing this feedback loop out of whack."
High fasting blood sugar levels, particularly in the earlier years of type 2 diabetes, result from this hormonal imbalance. Evening meals and snacks may get the blame for morning highs, but hormones are the likely cause.