What causes caffeine headaches and migraines?

Jun 14, 2014

In our other article, How to get rid of a caffeine headache or migraine, we covered how to get rid of caffeine headaches - but curious what actually causes caffeine headaches in the first place? Well, read on.

First: we’ll have back up a bit explore how caffeine exactly works once it enters your body.

Once you drink that cup of coffee or down that energy drink, caffeine gets absorbed to the bloodstream, where it’s consequently carried to the brain. There, caffeine tricks the brain by binding to adenosine receptors, which are normally binding sites in the brain that - you guessed it - bind to adenosine molecules.

The brain normally uses adenosine as a signaling molecule to let the body know to start winding down and get ready for sleep. When adenosine binds to adenosine receptors, then, the body starts getting tired. When caffeine binds to adenosine receptors, however, it doesn’t activate the receptors, but effectively ‘blocks’ them off so adenosine can’t bind.

As a result, the brain doesn’t know to start telling the body to get tired, and that’s why caffeine’s so effective in keeping you going when you’d normally be down and out in seconds.

But what happens when you use too much caffeine on a regular basis? The brain is adaptable and pretty smart, so what it begins to do is compensate for the fact that all its adenosine receptors are blocked by creating new receptor sites for adenosine to bind to.

Unfortunately, what this means is once you start drinking too much caffeine, your body soon requires you to drink more caffeine to get the same effect you used to, and pretty soon your usual dose only gets you to normal.

What that also means is when you skip out on your daily caffeine dose, suddenly your body has too many adenosine receptors, with too many adenosine molecules binding to all those receptors, causing you to be way more drowsy and tired than you should be and possibly even giving you caffeine headaches, migraines, and ‘brain fog’ - no good.

The good news is the fix for this problem is pretty straightforward. To get rid of your caffeine headaches…well, just read our article How to get rid of a caffeine headache or migraine!