What Happens in Your Brain When You’re Hangry?

Have you ever felt extremely angry and irritated out of nowhere, only to realize you hadn’t eaten in hours? That sudden wave of irritability when hunger strikes is what we’ve come to call “hanger.” 

Hangry is a term that refers to feeling irrationally angry, irritable, or moody because you’re hungry. And it isn’t just an excuse to snap at your partner over something trivial—research shows it’s a real thing.

Hanger is pretty common, says Noah Kass, DSW, LCSW, a licensed psychotherapist based in New York. “Stay away from food, and it becomes difficult to manage emotions and make rational decisions,” he says.

But why is hanger so powerful? Why does skipping a meal sometimes turn us into someone we barely recognize?

The Science Behind Hanger

As someone who’s been guilty of turning into a moody monster when my stomach growls, I always assumed it’s because my brain is panicking without food—that it’s going into “flight or fight” mode because it assumes I’m starving.

Turns out it’s a little more complicated than that. 

Peter Brukner, OAM, MBBS, FACSP, FACSM, FASMF, FFSEM,  a nutritionist and dietitian, explains that your brain needs glucose to function correctly. “If you do not eat for some time, your blood sugar goes down and your brain doesn’t have enough energy,” Dr. Brukner says. “This makes it difficult for you to think clearly, and it can change your mood.”  

Hunger impacts the delicate balance of glucose, hormones, and brain activity that keeps us feeling steady and calm.

When your blood sugar drops, your brain doesn’t get the energy it needs to function at its best. This lack of fuel leads to irritability, poor concentration, and impulsive behavior. In essence, your brain goes into survival mode, prioritizing the search for food over everything else.

Neuroscientist Camilla Nord, PhD shares another perspective. Dr. Nord writes about hanger—among other topics—in her book, The Balanced Brain: The Science of Mental Health. “I think of hanger not as hunger triggering a mood change, but as the brain’s (mis)interpretation of its internal state,” says Dr. Nord, who leads the Mental Health Neuroscience Lab at the University of Cambridge. 

Dr. Nord says that the brain constantly monitors the internal state of the body, a process called interoception, to help us survive. Interoception doesn’t just monitor the body for signs of hunger or illness, but for emotions.

She gives the example of a brain region called the insula, which detects whether or not you’re hungry and whether or not you’re angry.

“A big change in an aspect of your physiology—including not having enough oxygen, or in the case of hunger, food—is often experienced as an emotional change because it is a deviation from your homeostatic set-point,” Dr. Nord explains.   

In other words, when your brain detects that you don’t have enough food, it may confuse it for an emotion. 

Hormonal Responses to Hunger 

When blood sugar drops, your body releases stress hormones like cortisol and adrenaline to mobilize stored energy. While these hormones help you stay alert, they can also make you feel edgy and reactive.

When you’re hungry, your brain also produces a chemical called neuropeptide Y—a chemical that makes you feel more hungry. Dr. Brukner says that neuropeptide Y is also associated with aggression and anxiety, two hallmarks of hanger.

“These hormones try to help bring blood sugar back to normal, but they also start a ‘fight or flight’ response,” Dr. Brukner explains. “Because of this, you feel more nervous and on edge.”

These hormonal shifts are why being hungry can feel more like a crisis than a mild inconvenience.  

Psychological and Behavioral Effects

The brain relies heavily on glucose as its primary energy source. When glucose levels plummet, your brain struggles to function properly, leading to noticeable changes in mood and behavior.

Some common effects of hunger on your mental state include:

• Irritability: With less glucose available, the brain’s self-control center becomes less effective, making it harder to regulate emotions.
• Impatience: When you’re hungry, you may have less of a tolerance for delays or obstacles, making you more likely to snap at others.
• Impulsivity: Hunger can affect impulse control, and not just when it comes to food: One study found that hungry people are more likely to buy unnecessary nonfood items, too.
• Difficulty concentrating: Hunger can make it challenging to focus on tasks as your brain becomes fixated on finding food.

“If you experience anxiety, depression, or any mood disorders, hunger can worsen existing symptoms such as anger, fatigue, and mood swings,” says Dr. Kass. 

When you’re hangry, your emotional centers tend to take over, while your logical thinking takes a backseat. This can lead to overreacting in situations you’d typically handle calmly. 

Social Implications of Hanger

Hanger doesn’t just affect you—it can strain your relationships as well. 

A 2014 study, which involved 107 married couples, found that people with low blood glucose were more likely to stick more pins in a voodoo doll that represented their spouse.

It may seem like an odd way to measure aggression, but those who have been hangry might likely relate. When hunger-induced irritability takes over, you might find yourself snapping at loved ones, misinterpreting neutral comments, or overreacting to minor issues.

Dr. Kass says this is common. “When you are hungry, you often interpret other people’s words as challenging. You may misinterpret what they are saying, become defensive, and lash out,” he says. “This is because hunger shifts the focus to survival. You prioritize your immediate needs over cooperation or empathy for others.”

How to Manage Hanger

The good news? Hanger is entirely manageable. By making small changes to your routine, you can prevent hunger from taking over your mood and interactions.

Preventing Hanger

The best way to avoid hanger is to avoid hunger. This can be surprisingly tricky to do, especially if you have a busy lifestyle or if you’re consciously trying to cut back on calories.

Here are a few tips for keeping hunger at bay: 

• Maintain regular mealtimes. If you tend to forget to eat, try to set alarms for around the same time every day.
• Eat balanced meals. Dr. Brukner suggests a mix of healthy fats, protein, and slow-digesting carbs. 
• Get enough fiber. Fiber can help you feel fuller for longer. 
• Carry snacks. Dr. Brukner recommends nuts, a boiled egg, yogurt and fruit, or a slice of cheese with some vegetable sticks.  
• Stay hydrated. Thirst can also affect your mood, Dr. Brukner says, so drink water throughout the day—not just when you feel thirsty.

How To Cope When You’re Hangry

It’s not always possible to avoid hunger altogether. If you’re already hungry, and you start to feel that irritability creeping in, consider trying these strategies:

• Practice mindfulness. Take a moment to breathe. “Remind yourself hunger symptoms are temporary and relief will come once you eat,” Dr. Kass suggests. “Speak kindly to yourself, practice deep breathing, meditation and visualization techniques.”
• Communicate. If you’re with others, let them know you’re feeling hungry. A simple “I’m really hungry right now, so I might be a little short” can help prevent misunderstandings.
• Consider your timing. Now may not be the best time to confront your co-worker about a sensitive topic, or bring up a contentious issue with your housemate. Rather, put a pin in that conversation and bring it up when you’re (both) feeling sated.
• Avoid quick fixes. When you do finally eat, try to avoid those tempting sugary snacks. Too much sugar may lead to a spike-and-crash effect, says Dr. Brukner. This can leave you feeling worse later.

Long-Term Strategies for Avoiding Hanger

If you’re prone to feeling hangry, paying attention to your feelings and hunger cues can go a long  way.

Dr. Nord recommends learning to identify the difference between feeling hungry and feeling irritable or angry. “If someone is very good at telling the difference between hunger and negative emotions, they are less likely to experience hanger,” she notes.

Simply bringing awareness to hanger can help you feel better, Dr. Nord says.  “When you realize it is hunger, not true anger, the emotional features tend to dampen or go away,” she explains.  Journaling or using a mood tracker can be helpful for cultivating this awareness.

I think this is why so many people like the term “hanger.” These neologisms aren’t just amusing: they tell us that we’re not alone in our experiences. By adding hanger to my vocab, I feel better able to identify what’s going on in my body—which, in itself, can be quite a relief. 

Of course, not all irritability comes from hunger. If you’re feeling particularly on edge, but hunger isn’t the cause, consider other factors like stress or lack of sleep.

Next time you feel hanger creeping in, remember: your brain can’t run on empty. A small snack could be all it takes to get back to feeling like yourself.