After seven or eight hours of sleep, a drop in blood sugar might seem natural. Many diabetics, however, detect a spike in blood sugar in their morning readings. During sleep, the body releases various hormones that cause a spike in blood sugar, and as nurse and diabetes educator Christy Parkin explains on the American Diabetes Association's website, the normal response is a spike in insulin. But in diabetics, the body fails to respond properly, hence the rise in blood sugar. This is called insulin resistance. As MayoClinic.com notes, this generally occurs between the hours of 2 a.m. and 8 a.m., and it has several possible causes.
Insulin Resistance
To understand the causes of insulin resistance, you need to understand how insulin works. Insulin is like a shuttle bus. It picks up glucose--sugar--in the bloodstream for delivery to cells all over the body to use as fuel for energy. With diabetes, the blood sugar doesn't make it off the bus--it just keeps riding around the bloodstream. When insulin resistance develops, there are more passengers--sugar--than buses. The cells don't respond as they should, effectively prohibiting the buses from releasing their passengers. The pancreas responds by pumping out more shuttle buses--insulin--until it can no longer keep up. The body is then left with an excess of passengers and shuttle buses simultaneously. Insulin resistance can occur in people with pre-diabetes as well as those already being treated for the disease.
Dawn Phenomenon
The Cleveland Clinic explains one cause of insulin resistance as the "dawn phenomenon," which results from a series of natural changes in the body through the night. As your evening insulin dose naturally subsides, the body responds by releasing stored glucose, leading to a morning rise in blood sugar.
Somogyi Effect
Another possible cause of high morning blood sugar is the Somogyi effect. Several decades ago, biochemistry researcher Michael Somogyi, Ph.D., discovered that when diabetics eat too late in the evening, consume alcohol or take insulin too early in the evening, they experience a spike in blood sugar in the morning. In this case the cause of the morning spike, or insulin resistance, is "man-made."
Management Options
To determine the cause of your morning blood sugar highs, your physician may ask you to take a series of blood sugar tests during the night. According to the Cleveland Clinic, low blood sugar levels between 2 and 3 a.m. indicate the Somogyi effect; high blood sugar during this time may be due to the dawn phenomenon. Options for managing the morning highs can include changing medication, changing the time medication is taken, altering your nightly eating routine or switching to an insulin pump. Another option, mentioned by the American Diabetes Association, is a continuous blood sugar monitor. These monitors are equipped with alarms that warn you if your blood sugar gets too low or too high.
Considerations
Whether because of lifestyle or lack of insulin, diabetics commonly experience a morning high reading. If your morning blood sugar runs high consistently, or if your blood sugar continues to run high throughout the day, see your doctor. Any change in the management of diabetes should be made by a physician. High blood sugar readings can lead to many problems if not treated, including blood vessel and nerve damage as well as eye problems.
