Jenilee Matz has a master’s degree in public health and worked for the Centers for Disease Control and Prevention (CDC) as a health communications specialist. She writes for several health publications including Everyday Health, HealthDay, and Diabetic Connect.
People with diabetes know that a certain amount of ups and downs in blood sugar is normal. Your blood sugar can rise or drop if you're sick, stressed, exercise, or eat at a different time than usual.
If you notice your blood sugar is higher than your target number often, it's time to see your doctor. This may be a sign that your diabetes care plan is not working.
Some people still have spikes in blood sugar in the early morning hours for reasons that aren't so clear. This is more common in people with type 1 diabetes, but it can also affect people with type 2 diabetes. Here are common causes and solutions for morning high blood sugar:
The Dawn Phenomenon
The problem: A natural rise in blood sugar that happens between 4 a.m. and 8 a.m. Our bodies start doing things to get ready for the day by releasing hormones, then blood sugar rises, which may be caused by the liver producing glucose. This can be frustrating for people with diabetes because blood sugar may be high on some mornings no matter what you ate or how much you exercised the day before.
The solution: Treatment from your doctor can help. Your doctor can adjust your insulin so that peak action happens in the morning hours if you have type 1 diabetes. For people with type 2 diabetes, oral medications may help reduce how much glucose the liver releases in the early hours.
The Somogyi Effect
The problem: The Somogyi effect explains that morning blood sugar highs are the result of how your body responds to a low blood sugar reaction (hypoglycemia) you had while you were sleeping. Overnight blood sugar lows are risky because you can sleep right through them. They can be caused by taking more insulin than needed, not eating enough food, or drinking alcohol.
The solution: Your doctor may suggest having a snack before bed to prevent nighttime low blood sugar. Or, he or she may tweak how much insulin you need to take at night.
The problem: Sometimes insulin can wear off overnight.
The solution: Your doctor can fix this problem by changing your insulin regimen.
Know that can be tricky to figure out which one of these causes is behind your morning blood sugar highs, though. Your doctor may ask you to check your blood sugar at 3 a.m. for a few nights in a row. Your 3 a.m. numbers will be compared to your blood sugar readings before bed and upon waking. Then your doctor may be able to make a diagnosis and fix the problem.