Why Does Sugar Give Me a Headache?

Why Does Sugar Give Me a Headache?

Does eating sugar give you a headache? You are not alone.

The sugar headache, otherwise known as the Holiday Headache (because we eat so much sugar on Easter, Halloween, Christmas and other holidays) has a lot in common with a hangover but it strikes any time we overdose on sugar.


While most of us have experienced a sugar headache at some time in their lives it is not well-known in medical circles. It might even surprise you to learn that the exact causes of all headaches are a bit of a mystery. Scientists have discovered that both migraines and cluster headaches change blood flow in the brain,  but exactly how blood flow changes create a headache is unknown. The same is true of the sugar headache.

I view the sugar headache as a toxicity or dehydration event and while it might be an annoyance, it could also be the sign of something more dangerous. Let’s look at dehydration and toxicity and see how they might cause a headache.

Sugar Dehydration

Dehydration is a common way to get a headache and sugar can lead to dehydration. Eating too much sugar pulls water out of your body in two ways.

  • Dilution: When you eat too much sugar, your body has to dilute that sugar to keep it from harming your body. This means that water is pulled from all parts of your body to balance the large amount of sugar in your blood stream. While this water-pulling effect happens all over the body, it is your head that suffers the most.
  • Urination: One of the ways that your body has of getting rid of excess sugar is to dump it in your urine. This is especially true of diabetics, who have to go to the bathroom a lot.


The other way to think about sugar is to consider it a toxic event.

While your body runs on glucose (a simple sugar) it was never meant to have a ton of simple sugars running around in your blood. If you look to nature, you would find that there are almost no foods that contain the high amount of sugar you would find in any soda or piece of cake. If natural foods do contain a high amount of sugar it is often bound up and hard to get to (like in a sugar cane). The only way to get a large amount of sugar into your body is to have that sugar processed before you put it in your mouth.

Processed sugar and processed grains both act like sugar in your body and this is toxic to the very blood cells that carry the sugar throughout the body. (I explain this at length in my book Sugarettes).

Something Worse?

Sugar headaches can also be a warning. If you get sugar headaches often, you might just be diabetic or pre-diabetic. The best way to find out if you are diabetic is to go and see your doctor and have them run some blood tests, but here are the typical symptoms of diabetes:

  • Excessive urination: As I mentioned above, sugar acts like a diuretic and will spill sugar and water into the urine. Having to urinate a lot is often one of the first signs of diabetes.
  • Excessive thirst: Since diabetics are losing a lot of water (see above), they are often thirsty all the time.
  • Excessive hunger: Everyone has periods of time when they are hungry, but diabetics are hungry all the time (with strong cravings for carbohydrates, sweets and sugar). This is one of the strange things about diabetics: They have a lot of sugar in their bodies, but it is not being used by the cells so they are hungry all the time.

Sugar Headache

The reasons why sugar gives you a headache are many and not readily understood, but you don’t have to wait for a reason to stop the pain in your head.

You can stop your sugar headaches and give sugar the boot by trying my 30 Sugar Free Days Program. During the program, you will learn about foods that act like sugar and what you can do about your cravings. Make sure you understand that sugar is doing more harm to your body than just giving you a sugar headache, take this opportunity to learn from your headache that you shouldn’t be putting large amounts of sugar in your mouth and you need to make a change.

< Previous Article
Metabolic Syndrome
About the Author

I'm Dr. Scott Olson ND. I'm a Naturopathic doctor who specializes in diet, health, nutrition, and alternative medicine. I've written numerous books and articles on health, medicine, and alternative medicine I want to help you get healthy! Take a look at my blog and make sure you join in the conversation!

126 Comments on this article. Feel free to join this conversation.

  1. Laura October 29, 2014 at 3:39 pm - Reply

    My father has suffered from sugar headaches all his life. Every time he eats an excess amount of sweets, he will develop a headache or wake up the next morning with one. I suffer from the same thing. Our “excess amounts” are different but the time of the day we can have sugar is the about the same, nothing later than 1pm. We do not have diabetics in the family and we are not the only ones that suffer from sugar headaches. Now, is there a study that proofs people who suffer from sugar headaches are more prone or resulted in becoming diabetics? Although, I don’t crave sugars and I have built a rejection to sweets. Could I develop diabetes later on in life? I’m currently 26.

    • Dr. Scott October 31, 2014 at 7:33 am - Reply


      There are no connections between sugar headaches and eventually getting diabetes. It does suggest, however, that you (and your dad) are sensitive to the effects of sugar and should avoid it if you can.

      Dr. Scott

  2. Deborah October 29, 2014 at 2:47 pm - Reply

    Is there a quick way to get rid of the sugar headache after you’ve eaten the sugar?

    • Dr. Scott October 31, 2014 at 7:32 am - Reply

      Sorry Deborah, it is like a hangover. Eating sugar creates a wave of inflammation throughout the body and brain. You just have to ride it out.

      Dr. Scott

  3. Margaret October 19, 2014 at 4:31 pm - Reply

    I eat an all natural diet so the only sugar i usually have in my diet is natural sugars. But, last night i went to a bonfire and over-indulged in s’mores and candy and i have had a killer headache all day! Could the unusual amount of sugar i consumed nearly 24 hours ago still be giving me a headache?

    • Dr. Scott October 20, 2014 at 7:18 am - Reply


      Yes, consider the sugar headache like a hangover – it can last a while. But, if you headache last longer than a day and it is not common for you (such a migraines…), you should get it checked out by your doctor.

  4. Niall October 16, 2014 at 2:01 am - Reply

    How much sugar is required to trigger headaches? I have been struggling with headaches a lot lately, and have been mostly sugar-free. Yesterday however, I ate a small candy before bed, and woke up with brain-fog and headache and pain in my neck. This has happened a few times and I’m starting to think there is a connection, but the amount of sugar does not seem excessive… is it common to get sugar headaches 12-16 hours after eating sugar?

    • Dr. Scott October 19, 2014 at 2:24 am - Reply


      Yes, even a small amount of sugar can cause headaches and, yes, it can be delayed by hours. It is clear that either sugar is causing this problem or you are allergic to something in the candy you ate.

      Dr. Scott

Leave A Response