Australian GPs Begin Prescribing Time in Nature: What the Evidence Says

Aboriginal and Torres Strait Islander peoples have long recognized the importance of connection to Country for health and wellbeing. That connection covers relationships with land, waters, culture, community and identity.

What the reviews found

A recent review assessed nature prescribing for mental health. It examined 47 trials with almost 3,800 participants, covering nature walks, outdoor exercise and gardening.

Of those trials, 17 found significant improvements in mental health compared with control groups, particularly for depression, anxiety and stress. A further 15 found some benefits, though less consistently. The researchers concluded that nature-based activities show promise but that more rigorous studies are needed to understand longer-term effects.

Physical health may also benefit. A review of 22 studies on forest-based activities found improvements in blood pressure, heart rate variability and cortisol, a hormone linked to stress. Findings for blood sugar were less consistent.

How much time is enough

A common recommendation of two hours a week comes largely from a study of almost 20,000 adults in England. People who spent at least two hours in nature each week were more likely to report good health and wellbeing than those who spent none.

That study was observational. It found an association, not proof that two hours of nature causes better health. The time needed may differ between people, and there is no known ideal amount for everyone.

Does prescribing work?

Nature prescribing is a form of social prescribing, in which health professionals encourage patients to join activities that support their health. A prescription might involve regular park walks, community gardening or a local conservation group.

Programs elsewhere offer examples, including Canada's PaRx and Park Rx America in the United States. England's green social prescribing multi-site trial gave more than 8,000 participants access to nature-based activities, with community link workers supporting referred patients. Participants reported significant improvements in their mental health.

A review of 92 studies found that nature prescribing delivered by health or social professionals improved participants' blood pressure and mental health, and increased their daily step counts. The evidence for nature prescribing, however, remains limited.