High Blood Sugar at Night and What to Do About It

Going to bed with high blood sugar can be uncomfortable. The best way to counter high blood sugar, or hyperglycemia, at night is a routine that keeps your blood sugar balanced throughout the day.

High blood sugar occurs when blood glucose levels are too high. Though it is a well-known symptom of diabetes, you can still have high blood sugar even if you don't have diabetes. Diabetes occurs when your body can't produce enough—or sometimes any—insulin. Insulin is a hormone made in the pancreas that helps regulate blood sugar levels and stores excess glucose for energy.

Glucose levels change throughout the day and in relation to when you have last eaten. When your blood glucose is higher than 130 milligrams per deciliter (mg/dL) while fasting, 180 mg/dL approximately two hours after eating, or higher than 200 mg/dL when randomly tested, you are considered to have hyperglycemia.

young woman checking her phone at night

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Causes of High Blood Sugar at Night

There are many causes of high blood sugar at night, including: 

  • A dinner or bedtime snack high in carbohydrates: Eating starchy or high-sugar foods late in the day can lead to high blood sugar at night, as well as high blood sugar in the morning.
  • Illness or injury: Trauma can trigger a hypermetabolic response (a speeding up of metabolism), leading to high blood sugar.
  • Too little exercise: Exercise helps the body more effectively use insulin, so lack of exercise could contribute to high blood sugar.
  • Too little insulin or diabetes medicine: When the body does not produce insulin or does not use insulin effectively and you don’t properly take your injectable insulin or diabetes medicine, glucose can accumulate in the bloodstream.
  • Menstruation: Estradiol and progesterone are two hormones linked to a decreased production of insulin, which affects glucose metabolism and can potentially lead to high blood sugar.
  • Pregnancy: Hormone levels fluctuate during pregnancy. Diabetes that occurs during pregnancy is known as gestational diabetes.
  • Stress: Stress, as measured by levels of a hormone called cortisol, is linked to decreased insulin production. When your body doesn't have enough insulin, glucose cannot get into your cells and be used for energy. As a result, glucose builds up in the bloodstream, leading to high blood sugar. When people are stressed, they may also overeat sugary foods or adopt other unhealthy eating habits.

How High Blood Sugar Impacts Sleep

The symptoms you may experience with high blood sugar at night could make it difficult for you to sleep, including falling and staying asleep. Depending on when you eat prior to bedtime, your digestive system may wake you up at odd hours.

A related issue is known as the dawn phenomenon, which is when you wake up with high blood sugar in the morning. This can also be caused by overeating foods in the evening that cause high blood sugar.

Nighttime Snacks to Regulate Blood Sugar

The best nighttime snacks to regulate blood sugar contain a combination of protein, a healthy fat, and a limited portion of complex carbohydrates, meaning one with fiber.

There are many snacks that fit this standard, including:

  • A handful of nuts: According to the Department of Agriculture, a cup of unsalted mixed nuts without peanuts contains 23.3 grams of protein, 31.9 grams of fat, 31.3 grams of carbohydrates, and 10.5 grams of fiber.
  • Low-fat cheese and whole wheat crackers: A 100-gram (3.5-ounce) portion of low-fat cheese contains 10 grams of protein, 2.31 grams of fat, 33.85 grams of carbohydrates, and 1.5 grams of fiber. Whole wheat crackers contain 12 grams of protein, 12 grams of fat, 72 grams of carbohydrates, and 8 grams of fiber.
  • An apple and peanut butter: A 100-gram apple (or a little more than half a medium-size apple) contains 0.41 grams of protein, 14.05 grams of carbohydrates, no fat, and 2.1 grams of fiber. One tablespoon (16 grams) of peanut butter contains 3.6 grams of protein, 3.57 grams of carbohydrates, 8.18 grams of fat, and 0.768 grams of fiber.
  • Low-sugar Greek yogurt: Chobani’s Less Sugar Yogurts contain 9 grams of sugar per 5.3 ounces, 30% less sugar than the brand's other yogurts. The 2% milk fat yogurt contains 12 grams of protein per 5.3-ounce serving. It contains 2.5 grams of fat, 10 grams of carbohydrates, and no fiber.
  • Yogurt: Whether Greek or regular, yogurt has been found to reduce the risk of type 2 diabetes by 14% if consumed daily, according to a 2017 review.
  • Air-popped popcorn: A three-cup serving of popcorn with a few tablespoons of Parmesan cheese measures in at 135 calories, 4 grams of fat, 20 grams of carbs, 3.5 grams of fiber, and 6 grams of protein.

Supporting Healthy Blood Sugar Levels

Maintaining healthy blood sugar levels during the day is a good way to prevent high blood sugar at night. That means exercising regularly, taking the right amount of diabetes medications if you use them, and managing stress levels.

Lack of sleep itself is a risk factor for type 2 diabetes, so it is important to maintain a healthy sleep cycle as part of a healthy lifestyle.

A Word From Verywell

The genes you inherit as well as certain stressors in life are out of your control, but there are still steps you can take to maintain a healthy blood sugar level and avoid nighttime hyperglycemia. Start by anticipating stress triggers or events that may contribute to high blood sugar, and plan ahead. Eating a balanced diet, getting enough sleep, and engaging in physical activity can help you avoid high blood sugar.

If you notice unusual symptoms of high blood sugar in the evenings, such as sudden changes in vision, seek immediate medical attention. By recognizing that you are prone to nighttime high blood sugar, you can work to identify the triggers and mitigate the associated risks, thus reducing your chances of having long-term poor health outcomes.

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11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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