Nature and Health – The Science Behind Why We Need the Outdoors

Nature and Health – The Science Behind Why We Need the Outdoors

Our declining health is one of society’s biggest challenges. We live longer than ever before, yet we are less healthy. At the same time as our connection to nature has decreased, stress-related illnesses have increased. Research shows that access to nature and green spaces can significantly reduce stress and improve recovery by supporting both mental and physical health. Nature affects us in many ways — even when we’re not consciously aware of it. For example, physiological indicators like heart rate and cortisol levels change when we are exposed to natural stimuli such as trees, plants, water, or birdsong.

How Nature Affects the Body
Physiology is the study of how living organisms function — mechanically, physically, and biochemically. Many of our physiological reactions are linked to the autonomic nervous system, which regulates things like heart rate and hormonal responses. That’s why physiological measurements such as heart rate, blood pressure, and cortisol levels in saliva are often used to study stress.

What the Research Shows
Professor Yoshifumi Miyazaki at Chiba University in Tokyo has spent over 25 years studying forest bathing — the Japanese practice of immersing oneself in nature for health benefits. In one large study involving 24 forests and 280 participants, people who spent time in the forest showed lower blood pressure, heart rate, and cortisol levels than those in urban environments. They also had greater parasympathetic activity (the body’s “rest and digest” response) and reduced sympathetic activity (the “fight or flight” response), indicating deep relaxation and reduced stress (Park et al., 2010).

Urban studies show similar results. Access to parks and green areas in cities has been linked to improved health and longevity among city dwellers (Takano et al., 2002). In experiments by Song, Ikei, and Miyazaki (2013–2015), participants who walked along a park path showed significantly lower heart rates than those walking in urban settings with no greenery — even during colder months. These findings confirm that exposure to nature, in any season, lowers physiological stress.

The Cost of Disconnection
Despite the evidence, modern life often keeps us separated from nature. Many people spend nearly all their time in artificial, man-made environments. As a result, stress, anxiety, and depression have risen — and prescription medications are often used as quick fixes. While medication can be essential in some cases, it’s important not to overlook natural, evidence-based ways to support our wellbeing. One of the simplest and most powerful is to reconnect with nature.

Spending time outdoors, among trees, water, and sunlight, isn’t just calming — it’s a biological necessity. Nature helps regulate our nervous system, restore energy, and promote balance in both body and mind.