You know the feeling. Lunch is running late, the line is long, and suddenly the person humming next to you is the most annoying human on Earth. Then you eat a sandwich, and the whole world seems friendly again.
That grumpy, hungry mood has a name: hangry, a blend of "hungry" and "angry." Scientists haven't pinned down one single cause, but part of the answer is body chemistry. When you go too long without food, your body releases hormones to protect its energy supply, including adrenaline, the same hormone behind the fight-or-flight response. That can leave you feeling tense and on edge.
Your Brain Runs on Sugar
Glucose, a kind of sugar, is the main source of energy for your brain. So your body works hard to keep a steady supply in your blood. After a meal, the hormone insulin helps manage that sugar. Between meals, other systems step in to keep levels from dropping too low.
When blood sugar starts falling, the pancreas releases a hormone called glucagon, which tells the liver to make more glucose. If that isn't enough, the adrenal glands release epinephrine, better known as adrenaline. Later, cortisol and growth hormone can join in. Glucagon and adrenaline also rise during fasting and stimulate hunger.
The Fight-or-Flight Connection
Adrenaline plays a key role in the fight-or-flight response, the body's way of gearing up for an emergency. It increases blood flow to the muscles and speeds up the heart. That's helpful when you need to run from danger. It's less helpful when you're waiting for a waiter to bring the bread basket.
When blood sugar truly runs low, a condition called hypoglycemia, the body's reaction can bring on a fast heartbeat, sweating, nervousness, and hunger. Low fuel to the brain can add tiredness and confusion. Many scientists think a milder version of this stress response helps explain why hunger can shorten our tempers.
True hypoglycemia is actually rare in people without diabetes, because the body has so many ways to balance blood sugar. If you often feel shaky, sweaty, or unwell when you're hungry, talk to your doctor.
That Rumbling Is Part of It
Your stomach joins the protest, too. Even when it's empty, its muscles keep contracting. These contractions, which can turn into hunger pangs, are believed to be triggered by high levels of a hormone called ghrelin, an appetite booster made by the stomach. A pattern of contractions in the empty stomach and gut is even responsible for that embarrassing rumbling.
Once you eat, other hormones take over. Insulin and a gut hormone called CCK help switch off the feeling of hunger, while leptin and peptide YY help you feel full. No wonder your mood often improves a bite or two into a meal.
A Word Fit for the Dictionary
People have been grumpy before lunch for as long as there's been lunch, but the word is new. Oxford Dictionaries added "hangry" in August 2015, and the full Oxford English Dictionary added it in 2018.
It even helped with an old riddle. A popular word puzzle, which took off in the New York area in 1975, asks for the third common English word ending in "-gry" besides angry and hungry. There's no clear answer, but some people now offer "hangry" as a cheeky solution.
So if someone you love gets a little snippy before dinner, go easy on them. Their body may be sounding a small alarm. The cure is usually simple, and often comes on a plate.
