- Eating too much or too little sugar can trigger a headache.
- This is because sugar consumption affects blood sugar levels, and can lead to hyperglycemia or hypoglycemia, which both include symptoms like headaches.
- Sugar headaches are more common for people with diabetes, as they have more difficulty regulating blood sugar levels.
- This article was reviewed by Jason R. McKnight, MD, MS, a family medicine physician and clinical assistant professor at Texas A&M College of Medicine.
- Visit Insider’s Health Reference library for more advice.
There are many different types of headaches, and your diet can play a role in how often you get them. In fact, your sugar consumption may be an important factor, especially if you have diabetes, as abnormal blood sugar levels are known to trigger headaches.
Can sugar cause headaches?
Eating too much or too little sugar can lead to headaches. This is because how much sugar you consume impacts your blood sugar levels. For example, eating too much sugar can cause your blood sugar to become too high, which is called hyperglycemia.
“With high blood sugar, small amounts of swelling can happen in and around blood vessels and surrounding brain tissue, which can cause headache,” says Evan Barnathan, MD, a family physician at Central Maine Healthcare in Maine.
Additionally, high blood sugar is often accompanied by dehydration, which may trigger headaches.
On the other hand, eating too little sugar can cause blood sugar to become too low, which is known as hypoglycemia. When your blood sugar is too low, your body turns to alternate sources of energy from fat and protein, called ketones. The process is called ketosis, and it can lead to headaches, too.
For most healthy individuals, their bodies are able to regulate blood sugar levels and keep them within normal levels, even if they eat a big piece of cake. But those with diabetes aren’t able to effectively regulate blood sugar, so what they eat will have a bigger impact.
As a result, people with poorly controlled diabetes will experience headaches from high or low blood sugar more often, says Barnathan. If you don’t have diabetes, you’re most likely to experience sugar-related headaches if you go on a sugar detox or start a no-carb diet like the Keto diet, because your body may start ketosis for energy after a few days.
Hyperglycemia vs. hypoglycemia
Normal blood sugar levels are between 80 mg/dL and 130 mg/dL. When your blood sugar is higher or lower than that, it can cause headaches.
Hypoglycemia is when blood sugar levels are lower than 70 mg/dL. In addition to headaches, the symptoms of hypoglycemia can include:
- Feeling shaky
- Feeling nervous or anxious
- Feeling irritable or angry (this is especially common in children)
- Racing heart
If untreated, hypoglycemia can lead to more severe symptoms, like blurred vision and seizures.
Hyperglycemia is when your blood sugar is 130 mg/dL or higher before eating, or 180 mg/dL or higher two hours after eating. Other symptoms can include:
- Increased thirst
- Drinking liquids more frequently
- Urinating more frequently
- Blurry vision
- Weight loss
Barnathan says headaches will occur more often when blood sugar levels are above 200 mg/dL. For people with type 1 diabetes, hyperglycemia can lead to a dangerous condition called diabetic ketoacidosis (DKA), which can lead to coma or even death.
How to treat sugar headaches
If you have a headache and you suspect it is from high blood sugar levels, make sure you are hydrated, says Barnathan. Your headache may be partly from the dehydration caused by hyperglycemia. You can also take an over-the-counter pain medicine like acetaminophen (Tylenol) or ibuprofen (Advil) to help relieve your headache.
If your headache is a result of hypoglycemia, it is usually because you haven’t eaten, so eating a healthy meal will help. For example,eating small meals throughout the day full of whole grains, fibre, and lean protein can help avoid hypoglycemia.
If you have diabetes, make sure you always have a fast-acting carbohydrate with you, like juice or glucose tablets. These carbs can be quickly broken down into sugar, so you can raise your blood sugar fast before it drops dangerously low.
If you don’t have diabetes, but recently cut sugar out of your diet and are experiencing headaches, make sure your body has complex carbs to break down for energy. That will help avoid ketosis and the accompanying headaches. Complex carbs include:
- Whole grains like oatmeal or bread
- Vegetables like peas
- Legumes like beans
While anyone can experience a headache from eating too much or too little sugar, it is most common for people with diabetes.
It is important for diabetes patients to follow the treatment plan designed by their doctor in order to maintain healthy blood sugar levels, says Barnathan. This will help prevent headaches and other diabetes-related symptoms.
“If you’re experiencing chronic headaches and you’re worried this is due to poorly controlled diabetes, you should discuss this with your doctor,” says Barnathan.
Related stories from Health Reference:
- How to get rid of a headache: 4 ways to quickly relieve head pain
- 5 of the best foods to lower blood sugar and manage diabetes
- How to lower your blood sugar quickly and what to do if it’s an emergency
- Why it’s so important for people with diabetes to limit their carb intake
- Why your blood sugar is high in the morning and how to lower it
Business Insider Emails & Alerts
Site highlights each day to your inbox.