The effects of nature on physical and mental health have been well documented across a wide variety of studies over many years. Just 15-20 minutes of outdoor time a day can stimulate the immune system and regulate circadian rhythms, lower blood pressure and heart rates, reduce nervous system arousal, decrease anxiety, improve mood, increase self-esteem and improve our cognitive function.
We all know anecdotally that we feel better after we go outside. Just as we know we all feel better after physical activity. Unfortunately, knowing and doing are often different things.
There is lots of research and studies out there but I liked the synopsis provided by Pub Med. Pub Med did a scoping review of 952 articles with varied methods of research. They narrowed the study down to 39 articles for final analysis utilizing inclusion and exclusion criteria and all 39 articles were from 2015 forward. They looked at the effects of Nature-based health interventions (NBI’s), such as educational interventions, physical activity, wilderness therapy, leisure activity, gardening and changes to the built environment.
Natural Outdoor Environments (NOE’s) were identified as green spaces, blue spaces and yellow, a mix of both. Green spaces included urban and rural environments. Examples of green spaces are urban forests, gardens, farms, wilderness, national parks or reserves, game reserves, urban stream corridors, playgrounds, meadows, bogs, or neighborhood green spaces. Blue spaces included the sea, rivers, fountains/seawalls, coastal areas, lakes, wetlands, oceans and beaches. Grey spaces were urban environments, including built environments such as swimming pools, urban landscaping, fields near housing developments, malls, hospitals, and homes.
It was found that Natural environments facilitated health benefits over built environments.
They used a variety of Health Outcomes to measure NIB’s. Examples of Health Outcomes used are Physical/Physiological Health, Cognitive Health, and Mental Health.
Mental Health outcomes were measured through Health-Related Quality of Life (HRQoL) or Quality of Life (QoL) surveys. There were improvements across all Mental Health Outcomes when engaging with nature (98%). Across all studies, NOE engagement had a positive association with mental health such as improved quality of life, and measures of depression and anxiety decreased with engagement of NOE’s. NOE engagement improved mood, self-esteem, self-confidence, and vitality. It also decreased mood disturbances, agitation, and behavioral problems such as hyperactivity or violence. Several studies also showed NOE’s led to improved social health, reduced social isolation, improved social connectedness, perceived stress reduction, and decreased psychological distress.
83% of studies looking at physical and physiological health outcomes found benefits across a range of outcomes when exposed to NOE engagement. Examples of measurements used were leisure-time physical activity, perceived physical activity, physical fitness, sedentary time, sleep quality and quantity, mobility measure, SystolicBP and Diastolic BP, baseline resting heart rate, and cortisol levels.
The effects of NOE engagement on Cognitive Health were measured by STEM-capacity, memory, attention restoration, and attention retention. Overall, the studies showed that 58% had positive effects on Cognitive Health when exposed to NOEW engagement. People with ADHD showed a decrease in symptoms by 8%.
Typically, certain factors were shown to facilitate well-being, such as biodiversity (unless it’s threatening, like a shark or predator), good weather, heat reduction, seasons, sound quality, perceived aesthetics, and connectedness to nature, which were all found to improve mental, physical, physiological, and cognitive health. Farm animals were also found to be very beneficial for autistic children.
Detrimental Environmental processes such as Air and Noise Pollution negated these effects.
WHO is dedicated to safeguarding health and enhancing well-being and has incorporated nature and biodiversity into their policies and protocols. They recognize the crucial role that nature plays in human health and well-being. In addition to the factors mentioned in the Pub MD review, WHO recognizes that exposure to the natural environment lowers the risk of chronic diseases. They also recognize that biodiversity and functional ecosystems support human health and well-being by air purfication, water filtration, and climate regulation. Climate change and the degradation of ecosystems can contribute to chronic diseases, and the spread of infectious diseases and zoonotic diseases. By recognizing these connections their public health initiatives are increasingly using nature and integrating nature-based solutions to protect and promote health and well-being. Embedding nature conservation and environmental sustainability in policies is essential for human planetary health. The US withdrawal from WHO in January 2026 was a huge loss to the health and well-being of the United States. It was a dedicated move by the administration to deny science and research that benefits our health. You can read about their policies through Europes Regional WHO Organization, WHO and the United Nations who work with WHO.
Bottom line is we all need to get outside every day and engage in some type of physical activity, and that will benefit our overall health and well-being. So think about the activities that you enjoy and pursue them knowing that you are engaging in healthful and enjoyable practices.
Gardening. Hiking. Swimming. Walking. Outdoor sports. Birdwatching. Beachcombing. Camping…
