You wouldn’t like us when we’re hangry

Being hangry is the anger one feels when one is hungry. It’s a very real state of being that can have relatively serious consequences.

Being hangry on the holidays is a particularly perilous predicament, as opportunities for relationship rumbles and familial feuds are at their most potent. Some may dismiss hanger as an internet joke endorsed by Buzzfeed listicles and the like, but there appears to be real science at play when it comes to feeling hangry.

A hormone called ghrelin has been pointed to as a possible spark for regrettable moments of hangriness. Known as the hunger hormone, your stomach releases ghrelin when it’s empty, to send the message to your brain that you’re hungry. So far, so useful. However, a recent study at the University of Gothenburg linked ghrelin to poor decision-making skills and impulse control, and it’s at this cross-section where hanger comes into play.

Ghrelin's links to poor impulse control appears to be just one part of the hanger puzzle. In his book Fat Chance: The Hidden Truth About Sugar, Obesity and Disease, nutrition expert Dr Robert Lustig says it's no coincidence that desserts spelled backwards is stressed. "Cortisol (a hormone triggered by stress) specifically increases our desire for comfort foods. Over several years, prolonged cortisol release leads to excessive intake of high-fat and high-sugar foods." Coping with stress by reaching for cortisol-inducing foods is like fighting fire with fire, according to Dr Lustig.

Amanda Salis, a senior research fellow in the Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders at the University of Sydney put forward her take on the science of hanger in a 2015 article published on The Conversation. Salis argues that low blood glucose levels (otherwise known as blood sugar), caused by hunger, make concentration difficult, and that can lead to silly mistakes.

“Another thing that can become more difficult when you’re hungry is behaving within socially acceptable norms, such as not snapping at people,” writes Salis.

“So while you may be able to conjure up enough brain power to avoid being grumpy with important colleagues, you may let your guard down and inadvertently snap at the people you are most relaxed with or care most about, such as partners and friends.” Exactly the people you’re hopefully lucky enough to hang around with over Christmas. Perfect! Bring on those low-glucose rows.

Foods that can boost dopamine and serotonin levels have been found to improve people's moods, a helpful fact at Christmas time. Dopamine is a hormone involved in the reward or pleasure centre of the brain. In a study published in tThe Journal of Neuroscience in 2002, researchers concluded that caffeine stimulated an increase in dopamine levels.

The old adage of everything in moderation is still at play, even with dopamine-inducing stimulants such as caffeine, which is also psychoactive drug. A 2011 study at La Trobe University's school of psychological Sciences in Melbourne, Australia, found that five coffees a day or more was enough to increase the participant's tendency to hallucinate. In the study, led by Prof Simon Crowe, participants of varying stress and caffeine conditions were asked to listen to white noise and report each time they heard Bing Crosby's rendition of White Christmas during the white noise.

People high on caffeine were more likely to hear the song. But, guess what? The classic Christmas tune was never played during the experiment. Researchers concluded that the combination of caffeine and stress affects the likelihood of an individual experiencing psychosis-like symptoms.

So, what can be done to prevent sugary squabbles? How can we appease the ghrelin gremlin? Where can we get our dopamine doses from without inducing caffeine- fuelled catastrophes?

"A high-protein breakfast can help control hunger levels and the 'satiety reflex' throughout the day by answering the hormone ghrelin," says Orla Walsh, consultant dietitian at Dublin Nutrition Centre. "Ghrelin works on a cycle, rising before meals and dropping after meals. Eating at regular intervals, starting with breakfast, is in sync with this hormone's cycle."

Prof Salis warns against the hankering for quick-fix foods, such as chocolate and potato chips, in the hunt for a hanger cure. “Junk foods generally induce large rises in blood- glucose levels that come crashing down fast,” Salis writes. “Ultimately, they may leave you hangrier. So think nutrient-rich, natural foods that help satisfy hunger for as long as possible.”

Prof Crowe’s team would no doubt suggest limiting your coffee intake to one or two cups a day, and Dr Lustig would recommend avoiding sugars, particularly fructose, and sugary processed foods.

“Dopamine seems to be positively impacted by a higher- protein breakfast, too,” says Walsh. “What’s more, eating enough of one particular amino acid called tyrosine prevents a bottleneck in the creation of dopamine. Tyrosine is found in meat, poultry, eggs, fish, cheese, soya beans and peanuts.”

So, according to these experts, having a proper breakfast of porridge with nuts and yogurt, eggs served with oily fish such as mackerel accompanied by some steamed spinach, with just one or two cups of coffee, should help keep your hanger levels at bay this Christmas.