It's completely normal to get grumpy when you're hungry.

Hangry is the official term. That feeling that you could strangle someone who says ‘good morning’ to you, but actually only because you haven't had breakfast.

Hangry stands for hungry and angry, at the same time. And that's actually very normal, say experts. It's a natural reaction of the brain to an empty stomach. In your brain, you have specific neurons that tell you when you need to eat again. If you don't give them what they want, they keep firing and active, causing areas of your brain associated with anxiety and a negative mood to be triggered. In short: a lot happens in your head that you are completely unaware of, but it clearly affects your mood. Suddenly you complain about the sun, you whine about a white shirt in the colored wash, and you sulk about the wrong Nespresso pod in your cappuccino.

There's more. A lack of glucose also plays a role. Due to that deficiency, it's harder to concentrate and to keep your emotions in check. Glucose is like fuel for your brain: you need it to function a bit like a normal person. In other words: you snap quicker and you have a short fuse with anyone around you. You even become a bit more aggressive. A study at Ohio State University, where couples participated using voodoo dolls, for example, shows that participants with low blood sugar levels at the moment of poking the doll attacked it twice as hard as the group with the highest blood sugar levels. Uh okay, nice.

Additionally, your body also produces cortisol and adrenaline during a glucose deficiency: exactly the stress hormones you don't want when you want to behave nicely. So if you notice that you're grumpy, cranky, angry for no reason, and not seeing the world positively? Make sure to eat a sandwich. And how often? Eating a snack every four hours is definitely the key to happiness. Eating works wonders, according to science.