Nature Prescription / Grounding

Nature prescription programs are outdoor exposures or activities initiated by a healthcare provider from an outpatient clinic, which emerged to address the high burden of chronic disease and increasingly sedentary, screen-based lifestyles. ^[1] Nature-based interventions support people to engage with nature in a structured way, such as gardening, green exercise, and nature-based therapy in green or blue space. ^[2] Grounding, also known as earthing, refers to direct bodily contact with the Earth's surface, such as walking barefoot outdoors or using conductive systems indoors, to facilitate absorption of the Earth's electrons into the body. ^{[3] [4]}

Nature-based interventions are asset-based solutions proposed to improve mental health for community-based adults, with the most effective interventions offered for between 8 and 12 weeks at a dose ranging from 20 to 90 minutes. ^[2] Proponents of earthing propose that direct physical contact with the surface of the planet has anti-inflammatory and antioxidant effects, with mobile electrons in the grounded person thought to neutralize reactive oxygen species produced by oxidative metabolism. ^{[5] [6]}

A systematic review and meta-analysis of 50 studies including 16 randomised controlled trials found that nature-based interventions were effective for improving depressive mood, reducing anxiety, improving positive affect, and reducing negative affect, with less evidence that they improved physical health. ^[2] A systematic review of 31 randomized controlled trials of green prescription reported consistent positive benefits for psychological health and wellbeing, cardiometabolic health, physical activity, and inflammation, but noted that further studies with larger sample sizes and objective measures are needed. ^[7] A narrative review of nature prescription programs concluded that research is too sparse to draw patterns in health outcome responses and that more research is necessary to measure and increase patient adherence and to understand short and long-term health outcomes. ^[1] The earthing literature is dominated by narrative and advocacy-style reviews; one such review states that some 20 studies to date have reported physiological improvements when the body is grounded versus non-grounded. ^[3] For grounding in Alzheimer's disease, a review found the preliminary evidence promising but emphasised the need for robust clinical trials to validate grounding's efficacy in that population.

Nature-based interventions, specifically gardening, green exercise, and nature-based therapy, are effective for improving mental health outcomes in adults, including those with pre-existing mental health problems, suggesting they may be a suitable addition to maintenance treatment. ^{[2] [9]} Green prescriptions can be effective across psychological, cardiometabolic, physical-activity and inflammation outcomes, offering a low-cost lifestyle option, though the quality of evidence is only generally acceptable with most studies carrying some risk-of-bias concerns. ^[7] By contrast, grounding/earthing evidence remains weak and contested: the supporting literature is largely small, narrative reviews rather than large controlled trials, and reviews themselves call for robust clinical trials before it can be validated. ^{[8] [1]}