The notion that people get ‘hangry’ – irritable and short-tempered when they’re hungry – is such an established part of modern folklore that the word has even been added to the Oxford English Dictionary. Although experimental studies in the past have shown that low blood glucose levels increase impulsivity, anger, and aggression, there has been little solid evidence that this translates to real-life settings.
Now new research has confirmed that the phenomenon does really exist in everyday life. The study, published in the journal PLOS ONE, is the first to investigate how hunger affects people’s emotions on a day-to-day level. Lead author Viren Swami, professor of social psychology at Anglia Ruskin University, Cambridge, England, said: “Many of us are aware that being hungry can influence our emotions, but surprisingly little scientific research has focused on being ‘hangry’.”
He and coauthors from Karl Landsteiner University of Health Sciences in Krems an der Donau, Austria, recruited 64 participants from Central Europe who completed a 21-day experience sampling phase, in which they were prompted to report their feelings on a smartphone app five times a day. At each prompt, they reported their levels of hunger, anger, irritability, pleasure, and arousal on a visual analog scale.
Participants were on average 29.9 years old (range = 18-60), predominantly (81.3%) women, and had a mean body mass index of 23.8 kg/m2 (range 15.8-36.5 kg/m2).
Anger was rated on a 5-point scale but the team explained that the effects of hunger are unlikely to be unique to anger per se, so they also asked about experiences of irritability and, in order to obtain a more holistic view of emotionality, also about pleasure and arousal, as indexed using Russell’s affect grid.
They also asked about eating behaviors over the previous 3 weeks, including frequency of main meals, snacking behavior, healthy eating, feeling hungry, and sense of satiety, and about dietary behaviors including restrictive eating, emotionally induced eating, and externally determined eating behavior.
Analysis of the resulting total of 9,142 responses showed that higher levels of self-reported hunger were associated with greater feelings of anger and irritability, and with lower levels of pleasure. These findings remained significant after accounting for participants’ sex, age, body mass index, dietary behaviors, and trait anger. However, associations with arousal were not significant.
The authors commented that the use of the app allowed data collection to take place in subjects’ everyday environments, such as their workplace and at home. “These results provide evidence that everyday levels of hunger are associated with negative emotionality and supports the notion of being ‘hangry.’ ”
‘Substantial’ effects
“The effects were substantial,” the team said, “even after taking into account demographic factors” such as age and sex, body mass index, dietary behavior, and individual personality traits. Hunger was associated with 37% of the variance in irritability, 34% of the variance in anger, and 38% of the variance in pleasure recorded by the participants.
The research also showed that the negative emotions – irritability, anger, and unpleasantness – were caused by both day-to-day fluctuations in hunger and residual levels of hunger measured by averages over the 3-week period.
The authors said their findings “suggest that the experience of being hangry is real, insofar as hunger was associated with greater anger and irritability, and lower pleasure, in our sample over a period of 3 weeks.
“These results may have important implications for understanding everyday experiences of emotions, and may also assist practitioners to more effectively ensure productive individual behaviors and interpersonal relationships (for example, by ensuring that no one goes hungry).”
Although the majority of participants (55%) said they paid attention to hunger pangs, only 23% said that they knew when they were full and then stopped eating, whereas 63% said they could tell when they were full but sometimes continued to eat. Few (4.7%) people said they could not tell when they were full and therefore oriented their eating based on the size of the meal, but 9% described frequent overeating because of not feeling satiated, and 13% stated they ate when they were stressed, upset, angry, or bored.
Professor Swami said: “Ours is the first study to examine being ‘hangry’ outside of a lab. By following people in their day-to-day lives, we found that hunger was related to levels of anger, irritability, and pleasure.
“Although our study doesn’t present ways to mitigate negative hunger-induced emotions, research suggests that being able to label an emotion can help people to regulate it, such as by recognizing that we feel angry simply because we are hungry. Therefore, greater awareness of being ‘hangry’ could reduce the likelihood that hunger results in negative emotions and behaviors in individuals.”
A version of this article first appeared on Medscape UK.