Touch can do a lot of good - so far, so good. But to what extent do people benefit from it? How much touch is allowed? Who should touch and where? Does it even have to be another person with whom we come into physical contact? A research team from Bochum, Duisburg-Essen and Amsterdam analyzed over 130 international studies with around 10,000 participants to answer these questions. The researchers were able to prove that touch is particularly suitable for alleviating pain, depression and anxiety. More frequent touch is particularly beneficial, but apparently does not have to last long. Skin contact intensifies the effect. However, touching objects with social robots, heavy blankets or hugging cushions also showed a demonstrable effect. The team reports in the journal Nature Human Behavior from April 8, 2024 .
In infants, it should be the parents who touch
"We knew that touch is very important as a health intervention," says Julian Packheiser from the Institute of Cognitive Neuroscience at Ruhr-Universität Bochum. "But despite many studies, it remained unclear how it can best be used, what effects can be expected in detail and what the influencing factors are." Following the comprehensive meta-analysis, the team was able to answer many of these questions.Both adults and infants benefit from touch. "For infants, it is important that it is the parents who perform these touches; their touch has a better effect than that of caregivers," reports Dr. Helena Hartmann from the University of Duisburg-Essen. "In adults, however, there are no differences between familiar people and professional staff." The greatest effect of touch on adults was demonstrated by the numerous studies on the mental state of the test subjects. Pain, depression and anxiety decreased significantly. Touching also had a positive effect on cardiovascular factors such as blood pressure and heart rate, although the effect was less pronounced.
Even a short hug has an effect
A longer duration of touch, which averaged 20 minutes in the studies, did not significantly influence the result. "It is not the case that the longer the touch, the better," summarizes Julian Packheiser. Shorter but more frequent touching proved to be more beneficial. "It doesn’t have to be an expensive, long massage," says the researcher, "even a short hug has a positive effect." The researchers were surprised by the positive effect of being touched by objects. Social robots, stuffed animals, hug cushions and much more scored lower than people in terms of mental factors, but still showed a measurable positive effect."Our conclusion: touch that is desired improves the well-being of people with illnesses in clinical situations as well as healthy people," says Julian Packheiser. "Anyone who has the impulse to hug family or friends should therefore not hold back unless the other person refuses."
Many unanswered questions
For the researchers, this raises further questions about the potential of touch interventions for public health. For example, it remained unclear in the studies what quality the touch had for those touched. Another unanswered question is whether affective touch has a different effect than instrumental touch, such as hair washing at the hairdresser or certain procedures at the doctor’s surgery. The role of touching animals has also not yet been sufficiently researched, nor have cultural differences between different societies.The work was funded by the German National Academy of Sciences Leopoldina (LPDS 2021-05), the Austrian Agency for Education and Internationalization (Marietta-Blau scholarship), the German Research Foundation (project no. 422744262 - TRR 289), the Dutch Ministry of Science (OCENW), the European Research Council (ERC) and the Dutch Research Council (NWO).
Julian Packheiser, Helena Hartmann, Kelly Fredriksen, Valeria Gazzola, Christian Keysers, Frédéric Michon: A Systematic Review and Multivariate Meta-Analysis of The Physical and Mental Health Benefits of Touch Interventions, in: Nature Human Behavior, 2024, DOI: 10.1038/s41562’024 -01841-8