Feeling hungry and angry at the same time? Here's the reason behind it

Feeling "hangry" is more than a simple drop in blood sugar levels, say scientists who found that combination of hunger and anger may be caused by an interplay of biology, personality and environmental cues.

"We all know that hunger can sometimes affect our emotions and perceptions of the world around us, but it's only recently that the expression hangry, meaning bad-tempered or irritable because of hunger, was accepted by the Oxford Dictionary," said Jennifer MacCormack, a doctoral student at the University of North Carolina at Chapel Hill in the US.

"The purpose of our research is to better understand the psychological mechanisms of hunger-induced emotional states - in this case, how someone becomes hangry," said MacCormack, lead author of the study published in the journal Emotion.

When someone is hungry, there are two key things that determine if that hunger will contribute to negative emotions or not: context and self-awareness.

"We find that feeling hangry happens when you feel unpleasantness due to hunger but interpret those feelings as strong emotions about other people or the situation you're in," said assistant professor Kristen Lindquist.

The researchers first conducted two online experiments involving more than 400 individuals from the US.

Depending on the experiment, participants were shown an image designed to induce positive, neutral or negative feelings. They were then shown an ambiguous image, a Chinese pictograph, and asked to rate the pictograph on a seven-point scale from pleasant to unpleasant. Participants were also asked to report how hungry they felt.

The researchers found that the hungrier participants were more likely to rate ambiguous Chinese pictographs as negative, but only after first being primed with a negative image. There was no effect for neutral or positive images.

"The idea here is that the negative images provided a context for people to interpret their hunger feelings as meaning the pictographs were unpleasant," said MacCormack.

"So there seems to be something special about unpleasant situations that makes people draw on their hunger feelings more than, say, in pleasant or neutral situations," she said.

It is not just environmental cues that can affect whether someone goes from hungry to hangry, said MacCormack.

People's level of emotional awareness also matters. People who are more aware that their hunger is manifesting as an emotion are less likely to become hangry.

In a laboratory experiment involving more than 200 university students, the researchers asked the participants either to fast or eat beforehand.

After some of the students were asked to complete a writing exercise designed to direct their focus on their emotions, all participants were asked to participate in a scenario designed to evoke negative emotions.

Students were asked to complete a tedious exercise on a computer that, unbeknownst to them, was programmed to crash just before it could be completed. One of the researchers then came into the room and blamed the student for the computer crash.

Participants were then asked to fill out questionnaires on their emotions and their perception of the quality of the experiment.

The researchers found that hungry individuals reported greater unpleasant emotions like feeling stressed and hateful when they were not explicitly focused on their own emotions.

These individuals also thought that the researcher conducting the experiment was more judgmental or harsh. Participants who spent time thinking about their emotions, even when hungry, did not report these shifts in emotions or social perceptions.