RESEARCH
The Potential for Outdoor Nature-Based Interventions in the Treatment and Prevention of Depression
Summary
This is a conceptual analysis exploring the potential of outdoor nature-based interventions (NBIs) in the treatment and prevention of depression. Published in Frontiers in Psychology, the paper highlights the growing interest in using natural environments for mental health benefits, particularly given the significant burden associated with depression globally. The authors argue that to enhance the effectiveness of NBIs, it is crucial to understand their underlying mechanisms or ‘active ingredients’. They propose a non-exhaustive list of five clinically relevant candidate mechanisms that may explain the beneficial effects of NBIs on depression: stress, rumination, mindfulness, sleep, and exercise. The paper also emphasizes the importance of developing personalized approaches, not neglecting young people in research, and focusing on both treatment and prevention strategies. The authors call for methodologically rigorous research, including well-powered randomized controlled trials, qualitative research, longitudinal studies, and large prospective cohorts, to achieve these aims. The analysis is informed by a narrative review of existing literature on the relationship between nature and depression.
The analysis reviews the evidence suggesting that contact with nature can have numerous positive effects on both physical and mental health, potentially via mechanisms like stress reduction and restoration of cognitive function. They discuss each proposed mechanism in detail, citing studies that link them to both nature exposure and depression. For instance, stress is a well-known risk factor for depression, and NBIs have shown the ability to reduce both psychological and physiological stress. Mindfulness, defined as non-judgemental awareness in the present moment, is positively associated with nature connectedness and is considered a potential mediator. The paper also underscores several methodological issues hindering the field, such as generally low study quality, small sample sizes leading to insufficient statistical power, and a lack of long-term longitudinal follow-up in many intervention studies. Addressing the heterogeneity of depression and adopting a personalized approach are also highlighted as key considerations for future research and practice.
