How to Lower Morning Blood Sugar
By Matthew Garza
Trying to learn how to lower morning blood sugar? Here’s why your glucose levels rise in the morning and a few things you can try to keep them in range.
Waking up with high glucose levels (or hyperglycemia) may feel like it doesn't make sense. You spend several hours asleep, not consuming any carbs, and yet somehow your glucose levels are still high when you wake up in the morning.
Why does this happen? What can you do to make sure your glucose levels are safely in range in the morning? Learn more about some tips on avoiding high morning blood sugar levels so you can start your day off right.
Why does blood sugar go up in the morning? What is the dawn phenomenon?
There are a few main reasons why your glucose levels may be higher in the morning. One of these is known as the dawn phenomenon.
The dawn phenomenon occurs early in the morning between 3 am and 8 am while you are still asleep. As morning approaches, the body naturally signals your liver to produce glucose, giving your body the energy it needs for the start of the day. Caused by changes in hormonal levels, the dawn phenomenon happens to all people, with or without diabetes. However, for those without diabetes, insulin levels increase and they do not experience hyperglycemia.
Another reason you may experience higher morning glucose levels is because your injected insulin wears off. If your body has insufficient insulin during the night, your glucose levels may start to rise. To combat this, you may consider trying a new basal insulin, adjusting the timing and amount of your basal dose (if you inject insulin), or changing your nighttime basal rates (if wearing an insulin pump).
The last reason you may experience higher morning glucose levels is known as the Somogyi effect. This occurs if your glucose levels fall too low during the night, caused by too much insulin or medication. To respond, your liver produces more glucose to try to maintain your glucose levels, which may result in hyperglycemia. The Somogyi effect is not as common as the other reasons described.
Symptoms of high blood sugar in the morning
If you wear a continuous glucose monitor (CGM), or if you routinely check your blood glucose every morning, you can see whether or not you are experiencing early morning hyperglycemia. In addition, you may also experience some of the signs and symptoms of hyperglycemia, which may include:
- Frequent and excessive urination
- Increased thirst
- Increased food intake
- Blurry vision
What should your blood sugar be when you wake up?
Whenever possible, aim to keep your glucose levels in range between 70 and 130 mg/dL in the morning before you eat breakfast, and between 70 and 180 mg/dL at other times. For some people, including older adults or pregnant women, a slightly looser or tighter glucose range might be best, and you should discuss with your healthcare provider what your goals may be.
Managing your glucose levels is key to preventing short and long-term complications. Though the occasional high blood glucose won’t put you in immediate danger – consistently high glucose levels (over 180 mg/dL) over a long period of time are associated with complications of diabetes such as heart disease and stroke, chronic kidney disease, nerve damage, eye disease and more.
Additionally, high glucose levels – especially in people with type 1 diabetes – can put you in immediate danger. These high levels, if combined with high blood ketone levels, can cause diabetic ketoacidosis (DKA), a potentially life-threatening condition that occurs when a person has high blood ketones and not enough insulin. Symptoms of DKA include shortness of breath, fruity-smelling breath, nausea and vomiting, confusion, or loss of consciousness.
Techniques to manage your blood sugar in the morning
Based on your glucose levels and trends, there are a few things you can do to manage your glucose levels so they don’t run high in the morning. Some of these strategies focus on adjusting medications to better suit your needs. Other strategies include adjusting your exercise routine, as well as what and when you are eating before bed.
Check your blood glucose before bed. If you are running high right before going to sleep, your glucose levels may remain high throughout the night. To address this, consider changing what time you eat in the evening, along with the content of what you’re eating. Also consider adding some light physical exercise such as a 10-15 minute walk to lower your glucose if it is high. Depending on these adjustments, you may need to adjust how much mealtime insulin you take to cover it.
Avoid eating lots of food close to bedtime such as a large, late dinner or a nighttime snack. One strategy from Adam Brown includes eating a low-carb, early dinner, with no snacking afterward.
Make sure that you take enough insulin to cover your evening meal. An insulin dose that’s too low can cause your glucose levels to run high throughout the night and into the morning.
Exercising in the evening can be a good way to bring your glucose levels down in the morning, however, there is some risk. Exercise before going to bed may lower your glucose levels over the course of hours, which could lead to dangerous hypoglycemia while you sleep.
Morning exercise can be another helpful way to lower your glucose levels if your blood glucose levels are too high in the morning from the dawn phenomenon or another reason.
If your glucose levels are in range before bed, they may rise throughout the night without enough insulin. This can be especially true for people who take long-acting (or basal) insulin in the morning, since it may be wearing off before your next dose.
Consider changing the time of day when you take your long-acting insulin. You may also benefit from switching to either twice-daily basal insulin or ultra-long-acting insulin, or from starting on an insulin pump. Read our article, “Are You on the Right Kind of Insulin,” to learn more.
Check your blood glucose (or CGM) during the night between 3 am and 8 am. If you are running high during these hours, you may be experiencing the dawn phenomenon.
Talk with your healthcare team about finding the best nighttime insulin regimen for you. If you take basal insulin, you may need to delay the timing of your dose to as close to bedtime as possible. Another option is to try an insulin pump or automated insulin delivery (AID) system. AID systems will automatically adjust your basal insulin doses throughout the night to help keep your glucose levels stable.
If you have type 2 diabetes, talk with your healthcare team about your glucose-lowering medications to make sure that your treatment plan addresses hyperglycemia in the early morning.
Each person’s body is different, and you may experience a combination of these high glucose levels throughout the night and morning. If you have a CGM, you can better track your glucose levels throughout the night to identify trends. If you don’t use CGM all the time, ask your health care provider about a professional CGM, in which the device is put on by your healthcare provider for two weeks. Your healthcare provider can download the data and discuss it with you after the two-week period. Otherwise, the more frequently you check your glucose levels with a glucose meter, the better. Click to learn more about professional CGM and how to get the most out of your fingersticks.
Finally, share any trends you notice with your healthcare team so that you can find the best ways to stabilize your blood sugar for the entire night. And, as always, talk with your healthcare provider before making any changes to your medication regimen.
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