We’ve all been there.

It’s a little after the lunch hour, and neither a carbohydrate nor a carrot has passed your lips since breakfast.

Gradually, you notice your speech gets slightly mumbly and you start to get annoyed with the world for asking you to do things — like answer questions or think clearly. In a nutshell, you’re experiencing that word-of-the-moment: hangry.

When you eat, your body breaks food down into glucose, which it uses for energy. After you haven’t eaten for a while, your blood glucose level drops.

When your blood glucose level drops beyond a certain point, your body taps organs that release hormones to boost glucose in your bloodstream. The pituitary gland releases a growth hormone. The pancreas releases glucagon (GLUE-kuh-gon), which promotes the breakdown of stored sugar. In addition, the adrenal glands release adrenaline and cortisol.

Adrenaline is secreted during fight-or-flight scenarios, and cortisol is called “the stress hormone.” In other words, if your blood sugar drops too low, your body reacts as if you’re being chased by a bear while trying to finish a difficult work project.

Also coming into play are two genes that govern both hunger and anger. One gene produces a chemical that controls hunger and regulates anger and aggression. Some people tend to produce more of this chemical than others.

Luckily, there’s a pretty easy fix: Eat a snack.

But make sure that snack isn’t just junk food full of simple sugars. Those kinds of foods will just make your glucose spike, then crash. It’s best to go with nutrient-rich foods.

Next time you feel a cloud of anger — or, at least, irritability — settle over you, make a systems check. Are you hungry? How long has it been since you last had a meal? If the answers are “Yes” and “A while,” locate the nearest apple. The fog may clear pretty quickly.