For people who have diabetes, the Somogyi effect and the dawn phenomenon both cause higher blood sugar levels in the morning. The dawn phenomenon happens naturally, but the Somogyi effect usually happens because of problems with your diabetes management routine.
There’s no one-size-fits-all target for morning blood sugar levels. What level is best for you depends on your overall health, the type of diabetes you have, and your treatment plan. While general guidelines exist, your doctor will adjust them to fit your individual needs.
Insulin, Blood Sugar, and Sleep
Your body uses a form of sugar called glucose as its main source of energy. A hormone called insulin, which your pancreas makes, helps your body move glucose from your bloodstream to your cells.
While you sleep, your body doesn’t need as much energy. But when you’re about to wake up, it gets ready to burn more fuel. It tells your liver to start releasing more glucose into your blood. That should trigger your body to release more insulin to handle more blood sugar.
If you have diabetes, your body doesn’t make enough insulin to do that. That leaves too much sugar in your blood, a problem called hyperglycemia.
High blood sugar can cause serious health problems, so if you have diabetes, you’ll need help to bring those levels down. Diet and exercise help, and so can medications like insulin.
The Dawn Phenomenon
If you have diabetes, your body doesn’t release more insulin to match the early-morning rise in blood sugar. It’s called the dawn phenomenon, since it usually happens between 3 a.m. and 8 a.m.
The dawn phenomenon is common in people with both type 1 and type 2 diabetes, affecting about half of them. But there are a few ways to prevent it, including:
- Don’t eat carbohydrates before you go to bed.
- Take insulin before bedtime instead of earlier in the evening.
- Ask your doctor about adjusting your dose of insulin or other diabetes medicines.
- Use an insulin pump overnight.
The Somogyi Effect
The Somogyi effect also causes high levels of blood sugar in the early morning. But it usually happens when you take too much or too little insulin before bed, or when you skip your nighttime snack.
When that happens, your blood sugar can drop sharply overnight. Your body responds by releasing hormones that work against insulin. That means you’ll have too much blood sugar in the morning. It’s also called rebound hyperglycemia. The Somogyi effect is more common in people with type 1 diabetes.
Recent research using continuous glucose monitors (CGM) has raised questions about the Somogyi effect. Wearable CGM devices, which track blood sugar levels throughout the night, give a clearer picture of what happens while you sleep. These studies have found that the sharp drop in blood sugar overnight, followed by a high spike in the morning, is less common than previously thought. Some experts think that high morning blood sugar might be more related to the dawn phenomenon, inconsistent insulin doses, or insulin resistance rather than the Somogyi effect. Because of this, the idea of the Somogyi effect is still being debated, and more studies are needed to fully understand it.
Symptoms of Dawn Phenomenon and Somogyi Effect
Even though the Somogyi effect and the dawn phenomenon have different causes, they share similar symptoms. The main one is high blood sugar when you wake up in the morning. With the dawn phenomenon, you might have high blood sugar several mornings in a row.
Depending on how high your blood sugar is, you might also have more symptoms when you wake up, including:
- Increased thirst
- Increased hunger
- The need to pee more often
- Headache
- Irritability
Somogyi Effect vs. Dawn Phenomenon: How Do You Know Which One You Have?
The Somogyi effect and the dawn phenomenon both cause high blood sugar levels in the morning, but they happen for different reasons. The Somogyi effect occurs when your blood sugar drops too low during the night. In response, your body releases hormones that raise your blood sugar, causing it to be high when you wake up. By comparison, the dawn phenomenon is a rise in blood sugar that happens in the early morning due to naturally occurring hormones, like cortisol and growth hormone. Unlike the Somogyi effect, the dawn phenomenon isn’t triggered by low blood sugar and is a more common cause of high morning blood sugar levels.
Before your doctor can help treat your high morning blood sugar, they’ll need to figure out what’s causing it. To do this, they might ask you to test your blood sugar in the middle of the night — around 2 or 3 a.m. — for several nights. If you use a continuous glucose monitor (CGM), it will collect this data for you while you sleep.
If your levels are always low during that time, it’s probably the Somogyi effect. If not, it’s likely the dawn phenomenon. Knowing which is which will help your doctor come up with a plan to address it.
Takeaways
If you have high blood sugar in the morning, it could be because of the Somogyi effect or the dawn phenomenon. While both have similar symptoms, they have different causes: the dawn phenomenon happens naturally, while the Somogyi effect is triggered by a drop in blood sugar during the night. It’s important to figure out which one is affecting you so you can get the right treatment. Your doctor can then help you create a plan to better manage your morning blood sugar.
Somogyi Effect vs. Dawn Phenomenon FAQs
What causes the dawn phenomenon in diabetes?
Each morning, your body releases natural hormones that signal to your liver to produce more glucose, which gives you the energy to wake up. This process can raise your blood sugar levels.
How do you differentiate between the dawn phenomenon and the Somogyi effect?
The Somogyi effect is caused by low blood sugar during the night, while the dawn phenomenon isn't related to low blood sugar. Checking your blood sugar in the middle of the night, either manually or with a continuous glucose monitor, can help your doctor figure out which one you’re experiencing.
What are the symptoms of the Somogyi effect?
The main symptom of the Somogyi effect is high blood sugar when you wake up in the morning. You may also feel more thirsty or hungry, need to urinate more often, have a headache or feel irritable.
How can you prevent high blood sugar in the morning?
To manage your morning blood sugar levels, your doctor might recommend avoiding carbs before bed, adjusting your dose or timing of diabetes medicine or insulin, switching to a different diabetes medication, or using an insulin pump to give you more insulin early in the morning.
What is the best treatment for the dawn phenomenon?
The best way to treat the dawn phenomenon is by using an insulin pump. Your doctor can advise you on the best settings to help you manage your blood sugar levels.
