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The sensation of hunger is one of the strongest we experience. Even mild hunger can determine much of our feelings, thoughts, and behavior. But how may it affect our social behavior? Does hunger make us selfish?
This question has received surprisingly little empirical attention, and it is not clear whether there is a consistent, robust effect. Therefore, my fellow researchers and I conducted a series of four studies, in which we used a variety of methods and procedures.
Findings uncovered that hunger does not always make you selfish. What matters is interdependence. In situations in which you can only give to another person (and not receive from the other person), there is a small effect, such that hunger slightly lowers the amount you give. But in interdependence situations, in which you and another person can affect one another’s outcomes (when you may give and may receive), the effect of hunger on prosocial behavior is virtually absent.
In these experiments, various manipulations were used. The strongest manipulation was when participants could not eat for 14 hours prior to the study. Upon arrival, half of the participants received drinks and food (with 42 grams of sugar), whereas the other half did not, to create a hunger and a control condition. This clearly affected the blood glucose levels between those two groups, but it did not affect their prosocial behavior. In fact, in three of the four tasks designed to assess prosocial behavior, participants in the two conditions were about equally prosocial.
We also asked people what they thought would happen in a study like this. Interestingly, most people predicted that hunger does make people more selfish, thus overestimating the effects of hunger. Also, a large majority (79 percent) holds general beliefs that hunger makes people more selfish.
Why may people hold such beliefs? This is likely rooted in an overestimation of the power of self-interest. Previous research has revealed that people believe that most people are driven by self-interest, rather than noble goals as helping others or achieving fairness or an equal share.
This overestimation of self-interest seems to have strong and widespread implications. Most of us believe that people are self-interested. But more than that, people seem to be thinking that the real “selfish self” will become apparent when the stakes are high or when people are needy—such as when people experience hunger. And people may think that self-interest is the one and only motive when people are faced with other forms of scarcity, such as when resources are limited during a war or after a natural hazard.
The question is whether this “ultimately selfish self” idea is true. The study on hunger suggests that even in a situation of scarcity, people remain focused on the people surrounding them—their family, their friends, and perhaps even their community. There is research showing that in times of risks or scarcity we may see strong forms of selfish behavior as well as strong forms of cooperative behavior. Especially the experience of common fate, such as the risk of a natural hazard or a shared enemy, may make people come to like and help each other.
But why then do most of us think that people are basically self-interested? The most important reason is that most of us implicitly use a “better safe than sorry” heuristic. Believing that other people are naturally selfish may support our own (selfish) actions to defend ourselves from being exploited. After all, people are quite aversive to risk, and thus tend take the safe route. This is quite understandable, and in some situations, advisable.
But believing that most or all people are ultimately selfish has serious drawbacks as well. It is a mindset that may also lead to foregoing opportunities for fruitful exchange. If you communicate trust, and give people some benefit of the doubt, you are far more likely to receive, build, and sustain trust. And this is essential for promoting cooperative relations with other people around us.
As most of us know, the quality of our social networks—having good friends—is strongly associated with health and life expectancy. We simply live much healthier and more comfortable lives when we are around people that we like and trust. We are social animals. Therefore, even if we believe in self-interest, we are unlikely to project that general theory automatically on each and every person we meet. Small positive gestures can be important.
Ultimately, a mindset in which we give others the benefit of the doubt will increase the chances of making good friends that we can trust. And those are exactly the friends that you can count on when you need them the most—perhaps even in times of scarcity or hunger.
References
Häusser, J. A., Stahlecker, C., Mojzisch, A., Leder, J., Van Lange, P. A. M., & Faber, N. S. (2019). Acute hunger does not always undermine prosociality. Nature Communications, 10, 4052.
