Preventing elevated morning blood glucose levels

If you have diabetes, waking up to discover your blood glucose is inexplicably higher than it should be is a frustrating way to greet the day. Experiencing morning highs are common in people with diabetes as just about everyone at some time will have a morning high once in a while.

But what you don’t want to happen is to have it become a regular occurrence. If that is occurring frequently several times a week, you need to discuss this with your doctor. Figuring out why your blood glucose levels are elevated in the morning and how can they be prevented is important to achieving and maintaining good blood glucose control.

Why the rise in the morning?

There are three likely explanations as to what is causing abnormally high blood glucose levels in the morning:

· One of the most common causes of elevated morning glucose is usually eating too many carbohydrates before bedtime. Having a carbohydrate rich evening meal or snack can set you up for higher than normal blood glucose readings in the morning.

· A second possible cause could be from what is referred to as the “dawn phenomenon.” Even if you took your blood glucose before bedtime and it registered within normal limits, but then when you woke up and take a fasting blood glucose, in which it had significantly risen, then your morning highs may be the result of an increase in hormones due to the dawn phenomenon.

What’s happening is that when you are asleep, your body releases hormones that can reduce your body’s sensitivity to insulin. At the same time, you begin releasing stored glucose as your body prepares itself to wake up for the coming day. This combination of reduced sensitivity to insulin yet an increase in glucose being released into the bloodstream can result in an elevated blood glucose level when you awake.

· Thirdly, a condition known as Somogyi effect or rebound hyperglycemia, can be the culprit for high morning blood glucose. If you took too much insulin at bedtime, your blood glucose may drop too low during the night. When this occurs, your body begins to release stored glucose to protect you from hypoglycemia which can elevate blood glucose levels. Your blood glucose can also rise if the long-acting insulin your take in the evening or your insulin pump basal rate is not enough for your needs.

Figuring out the cause

To get a good picture of what is the reason behind morning highs, talk to your doctor or diabetes educator. They may suggest to do some detective work by checking your blood glucose at three different intervals during the night – check your blood glucose at bedtime, wake up at around 3 am to check again, and take a final reading at your normal wake-up time. Do this for about three nights in a row to be able to compare any significant changes at the various times. This can help tell you and your health care provider what is to blame for morning highs.

Wearing a continuous glucose monitor is also a good tool for figuring out what blood glucose is up to overnight. Ask your provider if they can set you up with a loaner device for three days to get an accurate idea of the cause.

How to prevent high blood glucose in the morning

Working together with your healthcare team can help to figure out how to correct elevated morning glucose levels. Here are some suggestions they may make:

· If you use insulin, adjust the timing of your long-acting insulin so that the peak action correlates with the rise in blood glucose levels.

· Monitor and adjust your evening carbohydrate intake. If you have a bedtime snack, choose a carbohydrate food with no more than 15-20 grams of carbs and also consume a food with at least 12 grams or more of protein. A high protein food will break down more slowly, preventing a fast surge of sugar into the bloodstream making blood glucose levels spike. Greek yogurt is a great snack containing fewer carbs and has a high protein content.

· Change the type or dose of your medication or evening insulin, or alter your overnight basal rate.