Nature-based mental health: research and implementation agenda

[Extract] Mental ill health is widespread, worsening, costly, and underfunded. Exposure to nature is advocated as a treatment, in addition to counselling and pharmaceuticals. Evidence that nature improves mental health is available from randomised controlled trials, longitudinal studies, and involuntary nature deprivation during COVID-19 pandemic lockdowns. Such evidence includes cognitive, affective, behavioural, physiological, and neurological measures across demographics and life histories. However, there is less supporting evidence for diagnosis, design, and effective dose and duration for nature therapy courses, and for incentives and obstacles to adoption.