Sugar is a vital component of your body chemistry. Too much or too little sugar can cause problems, including headaches. This is because sugar has a direct effect on your brain and nervous system. Learning how to maintain a proper level of sugar in your diet may prevent future headaches. If you have persistent headaches related to sugar, you should talk to your doctor.

Headaches caused by sugar have a lot to do with your blood glucose level. Glucose gives your body energy by entering your blood stream after you consume sugar. Your body maintains a proper blood sugar level by breaking down glucose with insulin.

Fluctuations in your glucose level affect your brain more than any other organ. These rises and drops can result in a headache. The headaches caused by glucose and your brain are also related to hormones activated by sugar levels.

How much sugar do you need?

It’s increasingly difficult to manage a proper sugar intake. Americans eat far more sugar than they should on average. The American Heart Association recommends women consume no more than six teaspoons of sugar a day and men consume no more than nine teaspoons. This is in sharp contrast to what Americans actually consume, which is 22 teaspoons for adults and 34 teaspoons for children daily.

Learn more: America’s deadly sugar addiction has reached epidemic levels »

In general, you should maintain a blood sugar level between 70–120 milligrams per deciliter (mg/dL). This number may change if you have diabetes or another health condition. Always follow your doctor’s recommendations about blood sugar levels.

Consuming a lot of sugar or not consuming enough may cause an occasional sugar-related headache. Some conditions, like diabetes, may also make you more likely to experience sugar-related headaches. That’s because you may have an increased risk for hypoglycemia or hyperglycemia.


Hypoglycemia is a condition caused by not having enough sugar in the bloodstream. Hypoglycemia occurs when your blood sugar levels dip below 70 mg/dL. This can happen after skipping a meal or going a long period of time without eating. If you have diabetes you may experience hypoglycemia frequently, as the body cannot control blood sugar levels on its own. This may be exacerbated if you’re taking prescribed insulin.

You may also experience reactive hypoglycemia. This is a rapid drop in your blood sugar after eating a meal. This occurs within four hours of eating. An example of reactive hypoglycemia is when you eat simple sugars, such as white sugar. This raises blood sugar fast and then insulin overproduces, causing a rapid decline in blood sugar.

Both types of hypoglycemia can result in headaches and migraines.

Low blood sugar may cause a general headache or even a migraine. A headache may be dull in nature and throb around your temples. You may also feel nausea with a headache or migraine caused by hypoglycemia.

Other symptoms of hypoglycemia include:

  • lightheadedness
  • weakness
  • sweating
  • sleepiness
  • shakiness
  • pale skin
  • heart palpitations
  • hunger
  • anxiety
  • mood changes
  • double vision or blurred vision
  • confusion
  • change in consciousness (if low blood sugar is severe)


Hyperglycemia is a condition caused by having a blood sugar level that is too high. This happens when your body is unable to break down glucose efficiently with insulin. Your blood sugar may rise above 180–200 mg/dL.

Experiencing a headache may be an early sign of blood sugar that is too high. Headaches associated with hyperglycemia may start out mild in nature and get worse as your blood sugar rises or maintains a high level.

Additional symptoms of hyperglycemia include:

  • frequent need to urinate
  • frequent thirst
  • blurred vision
  • fatigue

Eating a lot of sugar in a short amount of time may cause rapid changes to your blood glucose levels. That can lead to symptoms that some people describe as a “sugar hangover,” including:

  • headache
  • nausea or upset stomach
  • difficulty focusing
  • shakiness
  • tiredness or lightheadedness
  • mood swings

If you’ve eaten too much sugar:

  • try hydrating with water or another sugar-free drink
  • focus on eating whole foods without added sugar, such as nuts, eggs, or other foods rich in protein
  • engage in low-impact exercise, like walking, swimming, or yoga, to help get your blood flowing

If you experience frequent headaches tied to sugar intake or lack of sugar, contact your doctor. It may be the sign of a more serious condition, like diabetes.

Untreated hyperglycemia can lead to a serious condition called ketoacidosis. This condition happens when your body does not make enough insulin and cannot control your blood sugar levels. Instead of using glucose for energy, the body starts using fat to make energy.

Bring information to your doctor’s appointment about the frequency of your headaches, as well as any other symptoms you experience related to sugar intake or lack of sugar intake. You should also share your current medications and information about your lifestyle, such as diet, exercise, and alcohol and smoking habits.

Your doctor will likely test your glucose levels if they suspect that your headaches are related to your sugar intake. These tests may involve fasting, or eating a meal and then testing your blood sugar level. Your doctor will also ask about:

  • symptoms
  • daily habits
  • health history
  • other relevant information

An isolated headache may just require general treatment. This may include over-the-counter medications, homeopathic remedies, or stress reduction.

Immediate treatment of hypoglycemia should include increasing your blood sugar levels quickly. You can do this by drinking juice or a sugar-based soft drink, or eating a piece of candy. If your symptoms haven’t improved after 15 minutes, consume more sugar. If symptoms continue to persist after trying to raise your blood sugar, call your doctor.

Chronic headaches caused by sugar should be treated according to the advice of your doctor. If you have frequent hypoglycemia, you may need to have meals at regularly scheduled times and eat foods without simple carbohydrates, like white sugar. You may also need to adjust your eating schedule to eat more frequent small meals throughout the day.

Sugar-related headaches caused by diabetes requires a more in-depth treatment plan. Your doctor will work with you to develop this plan.

Read more: Is diabetes to blame for your headache? »

Avoiding the side effects of too much or too little sugar may be as simple as maintaining a healthy diet and other good habits, including:

  • reducing stress
  • exercising regularly
  • drinking plenty of water
  • getting enough sleep
  • moderating caffeine and alcohol
  • not smoking

Sugar may be an addictive substance, though studies are limited on the addictive effects of sugar on people. Sugar may also cause withdrawal-like symptoms in some people. You may need to slowly reduce your intake if you suspect you’re consuming too much sugar. Try replacing sugary foods and drinks with things that don’t have added sugar, like a piece of fruit or water with a squeeze of lemon juice. That can help you wean yourself off of the added sugars.

Learn more: The practical 12-step guide to breaking up with sugar »

Tips for prevention

  • Avoid skipping meals or going too long without eating. That can lead to drops in sugar.
  • Limit your intake of sweets. Eating a lot of sugar in one sitting may temporarily increase your blood sugar levels.
  • If you have diabetes, monitor your blood sugar regularly. Follow your doctor’s recommendations for the management of your condition.

Sugar-related headaches are not uncommon. They may be a sign of hypoglycemia or hyperglycemia. If you get headaches regularly, talk with your doctor. Maintaining a healthy diet and other lifestyle habits may reduce the frequency of these types of headaches.