Dawn Phenomenon: Why Blood Sugar is Elevated in the Morning
Jul. 01 2022
Do you wake up with higher blood sugar than when you went to sleep, or notice it creeping up as dawn approaches? It’s a very common experience called dawn phenomenon. In this article, we describe what causes dawn phenomenon and how to prevent it from happening.
What is dawn phenomenon?
A rise in blood sugar occurs for everyone around the time they wake up and is a normal process even for people who do not have type 2 diabetes. It happens because the liver releases glucose to start fueling the body for the coming day. For people without type 2 diabetes, the body naturally increases insulin production to handle the elevation in blood sugar.
For someone with type 2 diabetes, whose body can’t make or use insulin efficiently, the result is a rise in blood sugar that can linger past breakfast. We call this elevated blood sugar, after waking, the “dawn effect” or “dawn phenomenon.”
About half of all persons with type 2 diabetes have higher pre-breakfast glucose levels due to insulin resistance. Dawn phenomenon can increase A1C by 0.4%.
How does dawn phenomenon impact someone with type 2 diabetes?
Elevated blood sugars can take a toll both physically and emotionally. Starting the day with high blood sugar means it will likely stay elevated well into the day. Higher blood sugar leaves most people feeling tired, irritated or in a mental fog.
Consistently high morning blood sugar often leads to increased insulin resistance, a higher A1C and other common type 2 diabetes complications like weight gain.
The dawn phenomenon contributes to post-breakfast spikes, often leading to the highest glucose reading of the day after breakfast. This is due to a higher fasting baseline from the pre-dawn hormone effect.
Better control of morning glucose levels can be achieved by:
- Increasing the amount of exercise in the evening after meals
- Increasing the protein to carbohydrate ratio of the evening meal
Know Your Numbers
To get a handle on morning blood sugars, the first step is to know your blood sugar number upon waking and understand if it is higher than is healthy. For many people with type 2, it is recommended that your waking blood sugar is below 110 mg/dL but above 80 mg/dL. Please confirm the best target range for you with your health provider.
Tracking your morning glucose numbers is an important habit to adopt. As a member of Level2, you probably use a continuous glucose monitor, or CGM, that makes it easy to review glucose levels since it records them every five minutes into your smartphone. If you use the fingerstick and meter method, try pairing them with a notebook as a simple reminder to track.
If your morning blood sugar is higher than is normal, consider your actions over the last 24 hours. Did you have a high carbohydrate meal? Did you miss your evening walk or daily step goal? Sometimes, small actions you take the day before can determine where the next day’s level begins.
Tips to Guide You
Here are tips to help you with morning blood glucose spikes:
Go for a walk first thing in the morning.
Moderate-intensity exercise, like a brisk walk before breakfast appear to counteract the dawn phenomenon significantly reducing blood glucose fluctuations, and improving blood glucose control throughout the day.
Earlier evening meals.
Eating earlier in the evening gives you more time to bring glucose numbers into a healthy range prior to sleep. Starting the night off in range can help stabilize overnight and morning blood sugar levels.
Avoid carbohydrates at the end of the day.
Make it so your last meal of the day has the fewest carbohydrates.
Move your body after dinner and avoid snacking.
Being physically active before bed can help manage the impact of the dawn phenomenon. Try a 15-minute walk around the neighborhood after dinner or marching in place during TV commercials rather than getting up to get a snack.
Get a good night’s sleep.
Studies have linked poor sleep quality with the dawn phenomenon. Create an evening routine that will allow you to get 6-8 hours of uninterrupted sleep.
Connect with Level2.
For more important information to help you live well, connect with us. Level2 is a life-changing diabetes care pathway empowering people with knowledge, advanced tools and coaching to live smarter, live better and even live without type 2.