How do people cope with stress? Everyone is interested in this. How about cleaning yourself as a stress reliever? Mammals, such as rodents and primates, calm down when they self-groom. Inspired by these animal observations, we set out to explore whether cleaning one's own body serves a similar function in humans.

In an initial "visual simulation" study, we had participants watch a short real-life video clip that provoked stress. This video showed a stressed-out bungee jumper about to dive off a 134-meter high platform. Her friends counted down for her several times, but she was too scared to do it. Finally, just as she was about to jump, the clip ended. Next, the same participants were asked to watch one of three short video clips. One of the follow-up clips explained how to properly wash one's hands while the other clips were about a topic completely unrelated to cleaning (how to peel an egg or draw a circle). We found that the video clip about handwashing was the most effective for reducing participants' anxiety.

In another study, we showed the same stress-reducing effect when participants imagined and visualized the experience of having their body (arms, face, neck, and hair) cleaned with water, but not when they imagined and visualized touching their body to feel themselves thoroughly.

Moving on to "Real Experience"

Next, we created stress in our participants by making them do a highly stressful social performance in front of a panel of evaluators. After being stressed this way, participants had to evaluate antiseptic wipes before being exposed to yet another social performance situation. We measured their stress levels using physiological measures. Whereas half of the subjects evaluated these wipes by simply looking at them, the other half actually used the wipes on themselves. And, indeed, actually using the wipes reduced physiological stress more than just examining them.

Why can cleaning yourself help reduce stress? First, cleaning may have an adaptive biological function by separating physical threats (such as infectious pathogens) from the body. Therefore, cleaning may reduce the anxiety that comes from any threatening, stressful situation (especially when it is salient, like during the first COVID-19 lockdowns). Second, the act of cleaning may help separate negative psychological experiences—for example, past failures—from the self because the act of cleaning essentially is also about separation, but physically by removing dirt from one's hands. Just this physical experience of separation may serve as a concrete, sensorimotor basis for higher order mental functions of separation.

Hygienic care is a human universal across cultures and part of our everyday life. Cleaning ourselves is indeed one of the most recommended daily routines by the World Health Organization for reducing risks of disease and infection, providing significant personal and public health benefits. However, no previous research has focused on the stress-reducing function of cleaning ourselves. We found that both imagining and actually experiencing cleaning oneself can weaken the effects of stressful events. Therefore, everyday cleaning behaviors, mundane as they seem, may help people cope with the stressors they experience in daily life.

For Further Reading

Lee, S. W. S., Millet, K., Grinstein, A., Pauwels, K., Johnston, P. R., Volkov, A. E., & van der Wal, A. (2022). Actual and simulated cleaning attenuate psychological and physiological effects of stressful events. Social Psychological and Personality Science.

Kobe Millet is an associate professor of marketing at the Vrije Universiteit Amsterdam. His research interests include consumer psychology, environmentally (un)friendly decision making, and prosocial behavior.

Amir Grinstein is the Patrick F. & Helen C. Walsh Research Professor of Marketing and Thomas E. Moore Faculty Fellow at Northeastern University. His research interests include socially desirable behavior, public policy, and marketing strategy.

Koen H. Pauwels is the Distinguished Professor of Marketing at Northeastern University. Helping people make better decisions, his research interests include analytics and technology.

Spike W. S. Lee is an associate professor of management and psychology at the University of Toronto. His research interests include mind-body relations, morality, politics, antiscience, class, culture, language, and technology.