When I go to bed, my blood sugar is pretty close to normal. But when I wake up, it is almost always higher. I’m not eating anything right before bed or during the night, so why should that happen?
Your liver. The liver is the organ in your body that releases glucose (sugar) into your bloodstream throughout the day and night. It is perfectly normal for the liver to do this. In fact, for most people, the liver secretes extra glucose in the middle of the night and early in the morning – times when we’re not usually eating. It does this to supply enough energy to keep our brain, nerves, heart and lungs functioning through the night.
Now here’s the kicker: If your pancreas does not make enough insulin (or you don’t take enough therapeutic insulin) to stimulate the utilization of the glucose produced by your liver, your blood sugar may rise through the night. You may wish to speak with your healthcare team about adjusting your insulin program to better manage your liver’s glucose production.
A rebound. A rebound is a blood sugar rise that follows hypoglycemia (low blood sugar). One of the ways the body reacts to hypoglycemia is by producing hormones that help bring the blood sugar back up. Sometimes, these hormones take a while to work and can cause the blood sugar to “overshoot” and wind up higher than we want.
Some people who take insulin may experience mild bouts of hypoglycemia during the night while they are sleeping. The low blood sugar might be mild enough not to wake the person, but the hormone production that accompanies the low can cause a “rebound” high reading by morning. To verify if this is the case, someone on your healthcare team may ask you to check your blood sugar once or twice during the night or wear a continuous glucose monitor. If your blood sugar is dropping below 70 mg/dL and then rising by the time you wake up in the morning, your team may suggest reducing your nighttime insulin or having a bedtime snack.
Pizza. Well, not just pizza. Any kind of big, high-fat, slowly digesting dinner can cause the blood sugar to rise after we go to bed at night. Large meals take longer to digest than small meals, and when meals contain large amounts of fat, as is the case with most restaurant and takeout food, the stomach may empty even slower than usual. Some foods are naturally resistant to digestion and take a while to raise the blood sugar. Also known as “low-glycemic-index” foods, they include things like pasta, nuts, beans, fresh vegetables and most high-fiber foods. Preventing a delayed blood sugar rise when having large, high-fat or low-glycemic-index meals requires careful planning. Some people may work with their healthcare team to adjust their insulin. Others employ after-meal exercise. A registered dietitian (RD) or certified diabetes educator (CDE*) may be able to work with you to find a safe and effective solution.
Gary Scheiner, MS, CDE*, is a Certified Diabetes Educator and Masters-Level Exercise Physiologist who has lived with type 1 diabetes for more 28 years. He was named 2014 Diabetes Educator of the Year by the American Association of Diabetes Educators, and has written six books, including Think Like a Pancreas. Scheiner and his clinical staff provide diabetes management consultations worldwide via phone and the Internet through his practice, Integrated Diabetes Services. Scheiner is a paid contributor for The DX. All opinions contained in this article reflect those of the contributor, and not of Sanofi US, its employees, agencies, or affiliates.
*“Certified Diabetes Educator” and “CDE” are certification marks owned and registered by the National Certification Board for Diabetes Educators (NCBDE). NCBDE is not affiliated in any way with Sanofi US. NCBDE does not sponsor or endorse any diabetes-related products or services.
© 2015 The DX: The Diabetes Experience