Sugar-Related Headaches Are Real — Here’s How It Happens

Shot of a uncomfortable looking woman holding her head in discomfort due to pain at home during the day
Getty Images | PeopleImages
Getty Images | PeopleImages

A sugar stat to swallow: along with acne, weight gain, and mood swings, sugar can also play a part in triggering painful headaches.

You might assume they're triggered by too much sugar at one time (and you're actually right), but consuming too little sugar can also contribute to the problem, Dr. Anisha Patel, DO of Medical Offices of Manhattan, explains.

"Sugar-related headaches come from a rapid swing in your blood sugar level," Dr. Patel notes. "So it's not actually the sugar itself that causes the headache but the quick change in consumption."

That could explain why you might have experienced a headache after, say, intermittent fasting or eating a large bowl of ice cream with plenty of fudge topping.

According to Dr. Patel, glucose level fluctuations affect your brain more than any other organ, and it's normal for someone without a medical condition to experience a headache under these types of conditions.

Sugar-related headaches could also be symptoms related to hypoglycemia and hyperglycemia, which Dr. Patel says aren't diseases themselves but rather symptoms or indicators of a larger health problem.


Blood sugar dropping too low is known as hypoglycemia, which "can be caused by sugar withdrawals — caused by very strict dieting (especially when the diet involves skipping meals), and delayed or irregular meals," Dr. Eric Ascher, DO, Family Medicine Physician at Northwell Health, explains.

"You may experience fatigue, moments of confusion, lightheadedness, and weakness, and many will complain of a headache — sometimes migraine-like in nature. Although rare, if your body experiences hypoglycemia for too long, you are at risk for coma and death."

Dr. Patel adds that hypoglycemia is often associated with diabetes treatment and can also be a side effect — although rare — of medication, alcohol consumption, severe liver illnesses, or hormone deficiencies.

"If you think you're experiencing a hypoglycemic attack, you should go to the doctor immediately," Dr. Patel says. "Those with diabetes or hormone deficiencies should consult their physicians about long-term symptom relief plans, which generally include a structured diet."

Reactive Hypoglycemia

Then there's a condition called "reactive hypoglycemia," more informally dubbed as "the sugar hangover."

"When we eat a carb-heavy or sugar-overloaded meal — especially if our body is unfamiliar with that much glucose, our body will supply a rush of insulin to help combat all that excess sugar that is shocking our bodies," Dr. Ascher explains. "Sometimes this may cause glucose levels to abruptly drop really low. This may cause hypoglycemia-like symptoms. Perhaps that is why you feel drained after a meal that concludes with a rich and heavy dessert."


On the opposite side of the sugar spectrum is hyperglycemia, which could also result in headaches. "Hyperglycemia occurs when the body is not producing or using enough insulin, the hormone that absorbs glucose into cells to be used for energy," Dr. Patel says. She adds that this is typically seen in diabetics.

However, Dr. Ascher says if your headaches are associated with increased thirst, increased urination, and blurred vision, you should speak with your doctor so they can monitor your blood glucose levels.

It's important to note that Dr. Ascher says that nondiabetic individuals normally have ebbs and flows in glycemic levels, as the body has capabilities to deal with these fluctuations; however, those with diabetes need extra support with medication.

Sugar Headache Relief

If you think you have a sugar headache that is related to diabetes, hypoglycemia, or hyperglycemia — or simply deal with these headaches often — you should reach out to your doctor.

It's also important to take into consideration what else you ate prior to this headache popping up.

"Some people find that certain foods cause headaches, like chocolate and caffeine," Jeff McGrath, RD at Westchester Medical Center in Valhalla, New York, says. "Foods containing chocolate and caffeine often have added sugar, and one might falsely accuse the added sugar of being the headache-causing agent."

If you do have a headache due to too much sugar, McGrath says to stop eating sugar for the rest of the day and to consider limiting your daily sugar intake moving forward.

"Experts recommend limiting your sugar intake to less than 10 percent of your daily caloric allowance (15 grams of sugar provides 60 calories, for reference). Otherwise, to reduce headaches, try to stay hydrated and limit alcohol consumption, especially at your holiday parties and gatherings."