Headaches and blood sugar

Hypoglycaemia is a term used to describe blood sugar that is too low to sustain the energy needs of the body. It is often cited as a headache cause and you may already be familiar with its link to migraines. Blood sugar levels during a migraine attack are often low and the lower the level the stronger the pain. It can be confusing to some people that consuming large amounts of simple sugars, such as those in table sugar, could actually result in low blood sugar, but if we look at how blood sugar is regulated, it makes a little more sense.

How Does the Body Maintain Blood Sugar?Glucose is an important form of energy for the body and is provided from dietary carbohydrate sources such as potatoes, fruit and bread. After eating, glucose is transported to the bloodstream, where it is used to provide energy to cells.


A hormone called insulin helps to lower blood sugar from excess glucose by helping glucose to enter the cells. Glucose beyond immediate needs is stored in the liver and muscle cells in a form called glycogen. Between meals, your body utilizes this stored glycogen, converting it back to glucose to provide energy for the body. When you aren’t eating, your blood glucose starts to fall and this signals the production of a hormone called glucagon, which ‘tells’ the body to release the glycogen and convert it into glucose for immediate energy. This released glucose then raises your blood sugar to a normal level.

Some high sugar foods can raise blood glucose too quickly and excessively, however, and the body releases a great deal of insulin to ‘move’ the glucose out of the bloodstream and into cells. The sharp increase in blood glucose is then offset by a sharp drop from excess insulin, resulting in a ‘sugar crash’ as it is commonly called.

This means that if your blood sugar is not consistent and suffers from extreme up and down fluctuations, a headache may be triggered. This intense fluctuation both increases and decreases insulin levels, leading to problems with the regulation of other hormones called epinephrine and norephineprine. Blood vessels in your brain begin to contract and expand and the characteristic pain of a headache occurs.

Is Caffeine Okay?Caffeine generally doesn’t have a large impact on blood sugar if moderately consumed. If you enjoy a cup or two of coffee throughout the day, you’re not likely to trigger a headache. Consuming high caffeine drinks frequently, however, is thought to affect blood sugar, particularly if the drinks are consumed over a short period of time. Try to aim for lower caffeine drinks such as green tea and if you’re consuming cola drinks, you may want to consider a herbal tea or a soda without caffeine.

• Don’t skip breakfast. Your body requires fuel after 8 hours or more of sleep (We’ll assume you’re getting enough rest!). If you’re pressed for time in the morning, try a convenient breakfast bar. Be sure to read labels and choose a high-fibre one with additional protein and fats.

Blood sugar levels may be contributing to your headaches and if you feel there is a connection, it is wise to discuss any concerns with your healthcare provider. By eating regular balanced meals and avoiding excessive amounts of high glycaemic index foods, you can help to keep blood sugar steady and prevent painful headaches.