The word hangry was included in the Oxford Dictionaries for the first time just last year, but the idea that you can be angry and hungry (with the hunger driving the anger) has been around for as long as there have been hungry people.

The connection between hunger and anger was documented in the Minnesota Starvation Experiment in 1944, though that wasn't the study's focus. That year, Ancel Keys, who was by then already a famous nutrition researcher, was asked to figure out how the human body and mind deal with starvation.

Understanding how people changed when they were deprived of food was of particular interest because of the thousands of refugees and prisoners-of-war who had been starved during World War II. Keys wanted to provide a useful, fully researched manual for relief workers dealing with populations of people who had long been without sufficient food.

The experiment involved 36 men and went on for 13 months. During the first three months, the participants were equalized on diets of 3,200 calories a day. Then, they were dropped down to 1,600 calories (with some slight variations, but all were cut 50 percent). According to Kelsey Miller's reporting at Refinery29, "They had basic daily work assignments, were required to walk 22 miles a week, and keep a diary. But aside from mealtime, there were no restrictions placed on their social lives."

Two pages from the Men and Hunger study. This is what men who were on a semi-starvation died actually felt. (Photo: Ancel Keys/Men and Hunger)

The results found in Men and Hunger, Keys' manual that resulted from his experiments, surprised researchers then, and might surprise readers now, too.

While there were expected decreases in energy and motivation (anyone who's been on a restrictive diet knows how that feels), the researchers noted a more generalized apathy, punctuated by irrational anger — the very definition of hangry. Researchers also saw bizarre behavior, such as playing with food, pairing strange foods together, plate-licking and food obsessions.

Basically, the men in the experiment got both hangry and really, really weird about their food. They even got less interested in socializing, romantic interludes and friendships, and got into gum chewing, recipe collecting and water guzzling. Some even tried to steal food. "At parties, the subjects found conversation both difficult and pointless. They all preferred a solitary trip to the movies, adding that while they could recognize comedy, they never felt compelled to laugh anymore," according to Miller.

During the 20-week recovery period, the men were able to eat more normally again, but everything didn't just go back to the way it had been before the deprived period. Yes, the men gained weight as they consumed more calories and had greater energy almost right away. But the mental states of the subjects continued to decline. Mood swings continued and intensified, and irritability and aggression didn't let up — bolstered by the new energy the subjects had.

"In general, recovery during rehabilitation was a halting process, two steps ahead and one step backwards. The fluctuations in mood in the individuals were greater at the beginning of rehabilitation than at any point during the semistarvation," Keys writes.

It wasn't until three months later that most of the subjects' mood and socializing returned to pre-experiment levels. But something was left behind: For many of the men, disordered eating, including continuous eating and binge-eating to the point of sickness, dogged them.

This old study can bring perspective to our own diets, especially as the weather warms and we consider crash diets. Not only are you more likely to put back on weight lost by massively restricting your food intake, but you could end up negatively affecting your relationship to food for a lot longer than bathing suit season.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

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