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Forest Bathing And Mental Health: It’s in Our Nature

For approximately 99.9% of human history, human beings have evolved and lived in natural environments. Only recently have we started spending most of our time in urban areas, a lifestyle change that may impact health and well-being.

Researchers are exploring the health benefits of nature and, particularly, the relationship between spending time in nature and mental health.

Studies have shown that a practice known as Japanese forest bathing, which involves immersing yourself mindfully in nature, has several mental health benefits. Forest bathing may improve mood and emotional well-being while reducing stress levels.

What is forest bathing?

Forest bathing, called Shinrin-yoku in Japanese, is a traditional practice created in 1982 by the Japanese Ministry of Agriculture, Forestry and Fisheries. Japanese government recommendations have since included forest bathing as a preventive healthcare measure.

Forest bathing is a therapeutic technique in which you immerse yourself in a forest environment while focusing on the experience through the five senses (i.e., vision, smell, taste, hearing, and touch).

Japanese forest bathing is one type of nature therapy, also known as ecotherapy. These terms refer to a set of practices designed to improve immune function, prevent disease, and produce a relaxed state through nature exposure. Nature therapy can be done in various settings, such as mountain, savanna, beach, park, and forest environments.

In addition to forest bathing, ecotherapy includes interventions such as:

  • Animal-assisted interventions (e.g., animal-assisted therapy)

  • Bringing nature to your home (e.g., having a birdfeeder)

  • Green exercise (e.g., walking, running, exercising in nature)

  • Nature arts and crafts (e.g., writing, taking photographs, painting outside)

  • Therapeutic horticulture (e.g., cultivating a garden)

Forest bathing is a nature therapy that involves using your senses to immerse yourself in a forest environment.

Health benefits of nature

Studies investigating the effects of forest environments on humans suggest that the health benefits of nature include:

  • Decreasing hormones involved in the stress response (e.g., adrenaline, cortisol)

  • Decreasing signs of immune activation (e.g., natural killer cells)

  • Decreasing proteins involved in inflammation (e.g., interleukin-6, interleukin-8)

  • Enhancing emotional state (e.g., attitude, feelings, psychological recovery)

  • Improving cardiovascular markers (e.g., blood pressure, heart rate)

  • Improving metabolic markers (e.g., triglyceride levels)

  • Increasing antioxidant activity (e.g., glutathione peroxidase levels, biological antioxidant potential)

  • Increasing relaxation in the body and brain (e.g., alpha brain waves, beta brain waves)

Overall, nature interventions such as forest bathing have the potential to improve health in individuals with hypertension (high blood pressure), metobolic disorders, and acute or chronic inflammatory conditions. Forest bathing may also address stress and mental health conditions such as anxiety and depression.

While further research is needed to develop specific recommendations for these conditions, interacting with green spaces can benefit anyone trying to improve their overall health.

Nature and mental health

Japanese forest bathing and spending time in natural green environments has been found to improve mental health in a number of ways.

Enhancing emotional well-being

Forest bathing may decrease negative emotional states such as hostility and depression. Additionally, research has found that spending time in nature can promote positive emotions, such as happiness and feelings of awe, and provide an opportunity to reflect on feelings and emotions.

A study comparing a 90-minute walk in nature with a 90-minute walk along an urban road demonstrated that the nature group had decreased rumination (continuous thinking) about themselves and decreased activity in an area of the brain that is involved in human withdrawal, sadness, and reflection on negative emotional experiences.

Improving sleep

Forest bathing may support mental and physical health by improving sleep-wake cycles. A trial in healthy male and female individuals found that two hours of forest walking was associated with improved sleep time, immobile minutes during sleep, sleep quality, and self-reported depth of sleep. A greater increase in sleep time was seen with afternoon walks compared to walks taken before noon.

Influencing spirituality

Nature may also have a positive effect on well-being by enhancing or actualizing human spirituality. Spiritual health, one element of the World Health Organization’s (WHO) definition of health, means living in a way that leads to realizing your meaning, purpose, and full potential in life.

Managing psychiatric symptoms

One study observed the effects of a one-hour and 45-minute forest walk in individuals with affective and psychotic disorders. Both groups reported improvements in confusion, depression, and tension-anxiety. However, the individuals with affective disorders also reported improvements with fatigue whereas the individuals with psychotic disorders also experienced improvements with anger-hostility.

Reducing stress

Forest bathing may reduce stress and promote relaxation by reducing the production of cortisol, commonly known as the “stress hormone”, a marker used to measure stress in the body. A trial of 498 healthy adults that examined the psychological effects of forest bathing found that those who felt chronically stressed received the most benefit from the forest intervention.

Supporting individuals with alcohol use disorder

Research in individuals with alcohol use disorder assessed the psychological effects of a forest therapy intervention compared to following normal daily routines. The study found that the forest therapy group experienced a significant improvement in depression levels, with the greatest effects seen in individuals in their 40s with severe depression at the start of the program.

Discover the benefits of forest bathing.

1. Choose a forest environment

If it’s accessible to you, walking or spending time in a green forested area is associated with greater benefits than time outdoors in an urban (city) environment. Specifically, research suggests that short-term forest viewing and walking has a more significant positive effect on feelings of vigor, vitality, and self-reported recovery.

2. Immerse yourself in nature year-round

A number of studies have investigated the health effects of forest interventions during different seasons of the year. Overall, beneficial effects such as decreased blood pressure and enhanced immune function are seen all year but are greatest in late spring and summer. In the summer, the light conditions and high temperatures may improve the therapeutic effects of forest environments.

If you live in an area with a snowy climate, there may be additional benefits to forest bathing during winter. A study in Finland assessed psychological relaxation following exposure to either a snow-covered forest or building landscape during winter. The forest group experienced a decrease in negative mood and an increase in restorativeness, whereas the building landscape group reported opposite effects. The researchers suggest that snow in the forest may have had an additional calming effect.

3. Include mindfulness when forest bathing

Mindfulness may support a deeper connection with nature and further increase the health benefits of nature activities. Mindfulness, defined as a state of intentional and non-judgmental attention to the present moment, can be practiced in various ways.

You can incorporate mindfulness by following a video or audio recording of a meditation or breathing exercise in a natural setting. Practice mindfulness while forest bathing by paying attention to how you experience the forest environment through your senses—namely, noticing what you can see, smell, taste, hear, and feel in your surroundings.

4. Get outdoors in the early morning and early afternoon

The time of day can affect concentrations of terpenes, fragrant airborne compounds that come from forest trees and other plants. Terpenes, including a group called monoterpenes, exhibit beneficial effects such as anti-inflammatory and antioxidant activities.

A trial in an oak forest in Spain measured the concentrations of monoterpenes during different seasons and times of day. During the two peak months (July and August), monoterpene concentrations were highest from 6 a.m. to 8 a.m. and 1 p.m. to 3 p.m.These results suggest that there may be an added benefit to forest bathing in the early morning and early afternoon.

Spending at least 120 minutes per week in nature can increase well-being in individuals of different ages and health statuses.

5. Spend at least two hours per week in nature

A survey that included nearly 20,000 individuals examined the relationship between nature contact in the past week and self-rated health and well-being. Individuals who spent at least 120 minutes (two hours) in nature were more likely to report good health and high well-being. These benefits were seen whether the 120 minutes were spent in one long nature visit, or several shorter visits within the week. The positive association with health peaked at 200 to 300 minutes per week of nature contact.

Did you know? Research indicates that as little as ten to 30 minutes of quiet stillness in nature can lower cortisol levels.

You can integrate nature into your daily routine in different ways, such as visiting a park or greenspace during your lunch break or taking a trail walk with your kids or dog.

6. View nature virtually

Although it may seem contradictory, seeing nature virtually is an alternative if you can’t experience nature outdoors due to extreme weather conditions or other reasons. A study using 90-minute nature videos of the forest or ocean that included natural sounds found that viewing these videos had a relaxing effect, particularly when the individual was able to choose their preferred type of scenery.

The bottom line

Japanese forest bathing is a preventive healthcare measure that can improve your mental well-being and quality of life. Forest bathing is considered a cost-effective and accessible way to manage stress and the related health risks, as it can be practiced by anyone with access to green space. We encourage you to regularly get outdoors and experience the health benefits of nature for yourself.


Written by Karolina Zaremba, CNP

Medically reviewed by Dr. Natacha Montpellier, ND, B.Sc.


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