Impact of male-only lifestyle interventions on men's mental health: A systematic review and meta-analysis.

Despite rising mental health problems worldwide, engaging men to seek mental health support is challenging. Male-only lifestyle interventions have shown promise for improving men's physical health, but the overall impact of these programs on psychological outcomes is unclear. This review aimed to evaluate the impact of male-only lifestyle interventions on men's mental health and to identify if any study or intervention features were associated with effectiveness. A systematic literature search with no date restrictions was conducted across four databases and returned 15 946 citations. Nine studies were eligible for inclusion, representing 1427 participants. Risk of bias was generally low across studies, although none were specifically powered to detect changes in mental health. Overall, significant group-by-time effects were reported for 26% of mental health outcomes examined. In the fixed-effects meta-analyses, small-to-medium intervention effects were observed for mental health-related quality of life (SMD = 0.24), self-esteem (SMD = 0.51), and positive affect (SMD = 0.58). Insights into effective study or intervention features were limited because of the low number of heterogeneous studies. Although male-only lifestyle interventions have improved men's mental health in some circumstances, studies that are specifically powered to detect long-term changes are urgently required, particularly in groups with pre-existing mental health concerns.