IE 11 is not supported. For an optimal experience visit our site on another browser.

The science behind being 'hangry'

Yes, it's in your head, but not the way you think.
A woman eats a cheeseburger
Researchers say that hunger turns up the dial on anger.Dmitry Ageev / Getty Images/Blend Images

When I first heard a friend use the word “hangry” several years ago with a group of friends, I marveled at its accuracy. The portmanteau, a combination of “hungry” and “angry,” perfectly described the present disposition of our buddy Ryan, who was storming ahead of the group, desperately searching for a late night place to eat. We’d just gotten out of a long movie, and Ryan hadn’t eaten since lunch 10 hours ago — a fact he kept repeating to us. He was irritable, impatient and annoyed by our leisurely pace.

Since then I use the word “hangry” all the time (I experience hanger a fair share, myself, to be honest) but I’ve long questioned its scientific authenticity. Is “hanger” a valid phenomenon? Can the physical presence of hunger actually affect our brains and thus our mood, perceptions and reactions? We consulted experts to unpack the fascinating science behind hanger, which is indeed, a real thing.

Hunger turns up the dial on anger

“While it does seem like a silly colloquial term, ‘hanger’ has come about to describe this experience we’ve all had,” says Dr. Kristin Lindquist, assistant professor in the department of psychology and neuroscience at the University of North Carolina, Chapel Hill and co-author of the recent study “Feeling Hangry? When Hunger Is Conceptualized As Emotion”.

“[My colleagues and I] are interested in this phenomenon because we study emotions and what the more basic processes are in the brain that contribute to emotions. There does seem to be a physiological and corresponding psychological shift when we’re hungry,” she tells NBC News BETTER.

Through a series of tests, Dr. Lindquist and her team concluded that when hungry, people are more likely to be in a negative mindset than those who are sated. One of the tests put participants in slightly annoying situations — like being faced with a computer malfunction and having to start a tedious task over. The empty-stomached participants were overtly peeved, and later, when given an evaluation of the research assistant’s performance were much likely to give negative feedback, saying that the research assistant had “been judgmental towards them”, Lindquist says, “suggesting that hunger turns up the dial on your anger in the face of a frustrating experience.”

When homeostasis is disrupted, our brain sends signals of a problem

Why does this happen? In part it comes down to interference with the body’s homeostasis, or the body's sense of equilibrium, that hunger creates.

“Hunger as a state actually causes a lot of shifts in hormones, brain processes and the peripheral nervous system that are comparable to what we see in anger, fear and sadness,” explains Lindquist. “The reason we have emotions in the first place is to help our bodies maintain homeostasis. Your brain is always trying to monitor the body and make sure you’re in homeostasis and if you’re not, it sends a signal to the body that we have to shift some things. That shift out of homeostasis into this state [of needing food] is experienced as negative, [triggering] cascades of hormones like cortisol, fight or flight responses, and so on. Ultimately your brain is sending a signal to your body that things are not good and need to be figured out.’”

Hunger as a state actually causes a lot of shifts in hormones, brain processes and the peripheral nervous system that are comparable to what we see in anger, fear and sadness.

When our brains are deprived of glucose, we can’t filter our emotions as well

“We know glucose states are low when people are hungry, and that the brain requires glucose and doesn’t function properly in low glucose states,” says Dr. Veronica Santini, a clinical assistant professor, neurology and neurological sciences at Stanford Health Care. “The part of our brains associated with hunger, fear, anxiety and anger is called the limbic system. It starts automatic responses we have before they even come to consciousness in the higher brain area, which takes information from the limbic system and the environment and then modulates these primitive responses. This is why we’re not walking around yelling at everybody. But if you have low glucose levels, it means higher brain functions are not working as well as they could be, so there may be a breakdown in those higher brain functions that help us modulate primitive responses.”

Essentially, it’s not just our bodies that run on food, it’s our brains, and when we don’t have that critical glucose at the needed levels, “mechanisms of self-control over aggression break down,” Dr. Santini says, adding: “One study done in 2014 showed that aggression against your spouse increased when glucose levels were low.”

So, when you’re hangry, you’re not just more prone to snap at somebody because you’re hungry on a physical level, you’re actually hungry on a cerebral level, and the deprivation is causing your reactive filters to blur if not shut down completely.

What should you eat when you're hangry?

All experts consulted for this article agree that the best way to treat hanger is, quite obviously, to eat something — but be selective if possible.

“If you have the option to eat, eat something high in glucose because it is broken quickly down into ATP, the type of glucose that provides fuel base for the brain,” says Matt Johnson, an associate dean of undergraduate programs at Hult International Business School who teaches psychology and neuroscience-related electives. “Go for things like grains, berries and cereals. But food of any kind will help subside hanger.”

Quick tip: Nuts are a high in ATP food that can easily be found in vending machines.

Tune into your emotions if snacking isn’t an option

If you’re working a long shift or in any other situation where grabbing a snack just isn’t possible, but you feel the hanger setting in, try to bring awareness to your emotions.

“We had [hungry] participants in our study think about emotions and write a story about them,” says Dr. Lindquist. “The idea being that when you focus internally you may be less likely to allow the effects of hanger to unfold. [This act of introspection] nullified the effects of hanger.”

So, in a real life situation, what you may want to do when you feel your hanger flare up is ask yourself if you’re hungry (you may not actually know), and if the answer is yes, consider your state of irritability as a possible result of this need for nourishment.

You should also do your best to eat regular meals and snacks no matter how busy you are to prevent hanger. Santini underscores that “the human body likes structure and when things send it into disequilibrium we may feel it physically but also emotionally.”

You may feel hangry before you feel hungry

Some, like Santini herself, feel the negative mood effect of hunger before they feel the physical sensation of hunger.

“I don’t get a rumbling in my stomach or stomach pains when I’m hungry; instead, I notice my mood has changed,” says Santini. “Some people may feel things physically more and some may feel them more emotionally. Too often we separate physical symptoms and moods when in reality they are one and the same. The mind and body are one, so start to listen to your body and understand that ‘Hey, I may not be anxious right now but very fatigued,’ or ‘I may not actually be angry, but very hungry.’ I really think it’s important to start to understand what our body is signaling to us — and how.”

More "This is Your Brain On"

Want more tips like these? NBC News BETTER is obsessed with finding easier, healthier and smarter ways to live. Sign up for our newsletter.