This is why your blood sugar is so high in the morning

When you’re working hard to control your A1c — eating healthy foods, getting regular exercise, and keeping your stress as low as possible — seeing your blood sugar jump in the morning might feel like a gut punch. But it’s most likely an occurrence called the dawn phenomenon (which just so happens to be a great name for a cover band). But just because it’s common (it happens in about half of people with type 1 or type 2 diabetes) doesn’t mean you should just ignore it. Here’s why the dawn phenomenon happens, when it’s something to bring up to your doctor, and what you can do to help smooth out your morning glucose levels.

Key takeaways

• The dawn phenomenon is a natural rise in blood sugar that can happen in the morning due to hormonal changes.

• Occasional, small bumps in morning blood sugar are likely fine, but bring up large, persistent spikes with your doctor.

• You can help keep your morning numbers down by making smart breakfast choices, staying hydrated, and adopting nighttime routines that set you up for success.

The dawn phenomenon is a temporary bump in blood sugar that happens as part of your body’s early-morning wake-up routine, typically occurring between 3 a.m. and 8 a.m. While this pattern can happen to most people to some degree, these spikes can be more prominent in people with diabetes because their bodies don’t make enough insulin to effectively regulate blood sugar. In fact, studies show that more than 50% of people with diabetes experience the dawn phenomenon. It’s not necessarily a cause for concern, but frequent, significant spikes in your blood sugar can put you at risk for certain health issues, and prolonged high blood sugar could be a sign that your doctor may need to adjust your treatment plan.

It is all part of your natural circadian rhythm. In the hours before you get up in the morning, your body releases a batch of hormones — including cortisol, growth hormone, and glucagon — to help you feel alert and ready for the day.

The catch: Those same hormones signal your liver to release stored glucose. That’s great for giving you a quick energy boost in the morning, but it can nudge your fasting blood sugar upward, even before you’ve had breakfast. For people without diabetes, insulin usually kicks in at this point and handles that extra glucose. But for those with insulin resistance or diabetes, this morning glucose bump can be more noticeable. 

The dawn phenomenon isn’t the only reason your morning blood sugar may be higher than expected. There’s also something called the Somogyi effect, which raises glucose in the a.m. for a different reason. The dawn phenomenon comes from the body’s natural hormone surge before waking, but the Somogyi effect is more like a rebound: When blood sugar dips too low overnight (maybe because you skipped dinner or took too much insulin), the body responds by releasing stored glucose to correct it, then overshoots the goal. While the Somogyi effect is rare, a healthcare professional can help look at data from a continuous glucose monitor to see if that’s what’s going on.

It depends what we’re talking about. A small rise in blood sugar? That’s normal. However, if you have prediabetes or diabetes and you’re seeing large, persistent morning spikes, it could be a sign that something is off. 

But that doesn’t mean you need to panic. “I encourage people [with diabetes] to monitor their glucose and look for patterns rather than reacting to one morning number,” said Barbara Eichorst, MS, R.D., CDCES, vice president of health care programs at the American Diabetes Association.

This is because glucose can be affected by many factors, including food, physical activity, sleep, stress, illness, and medications. If morning glucose is consistently above the target your doctor has given you, Eichorst recommends bringing it up to your doctor. Understanding the pattern can help determine whether adjustments need to be made to your daily behaviors or medication.

Seeing a high blood sugar reading might make you think you should skip breakfast so it doesn’t go up any further, but that’s the wrong idea. “People might have an instinct to avoid breakfast because they don’t want to add fuel to the fire, but evidence shows the best approach is to have a balanced breakfast of protein, fiber, and complex carbohydrates,” says Vanessa Infante, Ph.D., R.D., CDCES, and founder of The Prediabetes Dietitian. “That will help your body handle glucose for the rest of the day.”

The reason for focusing on protein, fiber, and complex carbs is that those foods take longer to digest, which not only helps avoid a big spike in blood sugar in the short-term, but also makes you feel fuller longer. At the same time, you’ll want to avoid some popular breakfast options, such as fruit juice, sugary coffee drinks, sweetened cereals, and what Infante calls “naked carbs,” like a sweet pastry that doesn’t have any protein or fiber in it. Those will spike your blood sugar and then send it way down.

Here’s a good way to think about your breakfast:

Start with protein

When putting together your breakfast plan, choose a lean protein to anchor your meal. Infante points to Greek yogurt, eggs, and cottage cheese as excellent options. Rather have meat? Turkey- or chicken-based sausage can be a leaner alternative to pork sausage or bacon. You can also boost your protein intake by sprinkling protein powder into a smoothie or stirring it into your morning coffee.

Add fiber and non-starchy vegetables

This could mean folding spinach or peppers into eggs, blending greens into a smoothie, or topping oatmeal with berries and chia seeds. Fruit can also be a great way to add fiber to your diet, especially things like apples, pears, nectarines, and berries. Just keep in mind that tropical fruits — like bananas, pineapple, and mango — can be higher in sugars, so incorporate those in moderation.

Include healthy fats

Having fat in your meal can help you feel more satisfied after, but you’ll want to stick with unsaturated fats. They are better for heart health than saturated fat, and people with diabetes are already more likely to develop heart disease. You can find unsaturated fat in avocado (mash it onto whole-grain toast), nuts and seeds (add them to a yogurt parfait), and nut butters (try a spoonful with some sliced apple).

Choose whole foods over refined carbs

Where carbs are concerned, opt for whole grains. It takes your body longer to turn complex carbohydrates into sugar than simple carbohydrates, so you won’t see the same sudden spike in blood sugar. Try overnight oats topped with fruit and nuts, a quinoa breakfast bowl, or whole-grain cereal with an egg on the side. 

Hydrate first thing

One important factor for a blood-sugar-friendly morning might not come to mind right away: water. While you sleep, your body loses water through breathing and sweat, so you wake up mildly dehydrated. Starting the day with water helps kickstart digestion and supports your kidneys in regulating blood sugar. Adding water-dense fruits and veggies (think fruits like melon, grapefruit, or peaches and veggies like cucumber, zucchini, tomatoes, or peppers) to your breakfast can give you an extra hydration boost.

The best blood-sugar-friendly breakfasts have the whole package: protein, fiber, healthy fats, and whole grains. You don’t need to figure this all out yourself: The Weight Watchers Diabetes Program can help you make the best food choices for your blood sugar. Its nutrition plan is proven to help you lower your A1c (and lose weight),* with 81% of members with type 2 diabetes saying the program made managing their diabetes easier.** 

If you want some inspiration, though, here are some meal ideas:

Smoothing out the morning spikes in blood sugar caused by the dawn phenomenon isn’t always about what you do in the a.m. Blood sugar can be affected by many factors, so it’s important to look at how food, physical activity, and sleep might be contributing. Some examples of ways you can minimize your morning blood sugar the night before include: 

• Avoid late-night snacking (or swap out your current snack of choice for something more blood-sugar-friendly, like air-popped popcorn).

• Take a walk after dinner.

• Give yourself about two to four hours between dinner and bedtime.

• Go to bed a little earlier.

Another factor to consider is stress. In times of stress, your body goes into fight-or-flight mode, giving you a jolt of cortisol and adrenaline. That can have an anti-insulin effect, making blood sugar stick around longer. Stress can also interfere with your ability to stick with healthy habits, leading you to skip a workout or reach for an unhealthy snack. Managing stress can be hard, but simple techniques like mindfulness and establishing routines can help.

The dawn phenomenon is a bump in morning blood sugar that can be common among people with diabetes. It’s caused by hormonal changes linked to your circadian rhythm. While they aren’t always dangerous, large, persistent spikes in morning blood sugar should be discussed with your doctor. You can help keep these spikes in check by starting your day with plenty of water and a balanced, blood-sugar-friendly breakfast that includes protein and fiber. Getting plenty of sleep, managing stress, walking after dinner, and avoiding late-night eating can also help lower your morning blood sugar.