The physical and mental health benefits of touch interventions: A comparative systematic review and multivariate meta-analysis


Receiving touch is of critical importance for human well-being. A large number of studies have shown that touch promotes mental and physical health. However, effect sizes differ considerably across studies and potential moderators of touch interventions remain unknown to this day. We conducted a systematic review and a large-scale multivariate multilevel meta-analysis encompassing 137 randomized-controlled studies in healthy participants and patients (166 cohorts, 9617 participants and 643 effect sizes) to identify critical factors moderating touch and research on touch intervention targets. We found comparable and medium-sized (g ∼ 0.5) effects of touch on both mental and physical health. Touch interventions were especially effective in regulating cortisol levels and increasing weight in newborns, as well as in reducing pain, feelings of depression and anxiety for adults and children. Touch interventions involving objects or robots resulted in similar physical but lower mental health benefits than human interactions. Clinical cohorts profited stronger in mental health domains but showed comparable physical health benefits as healthy individuals. Familiarity between the touch dyad was inconsequential in children and adults but critical in newborns. The number of sessions positively correlated with increased mental and physical health benefits in adults and children while session duration did not show significant effects. Leveraging those factors that influence touch intervention efficacy will help maximize the benefits of future social touch interventions and focus research in this field.