Why do people get hangry (angry when hungry)?

Do you get grumbly when you’re hungry? How a lack of food can make you less tolerant...


Asked by: Rob Wilks, Leamington Spa

Maintaining composure in the face of provocation takes self-control and there’s a long-running theory in psychology that states self-control depends on blood glucose levels. When you haven’t eaten you have less glucose, meaning that your tolerance is likely to run out sooner.

In one study, psychologists gave married participants a voodoo doll to represent their spouse. Each night for 21 nights, the researchers measured the participants’ blood glucose levels, and told them to stick as many pins in the doll as they wanted based on how angry they were feeling. The participants with the lowest glucose levels stuck in the most pins.

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