Forest Bathing and Earthing

What is it?

Forest Bathing

Shinrin-Yoku is a Japanese practice of Forest Bathing. Essentially it involves immersing oneself in nature. Traditionally this was defined as walking through the forest and has now expanded to include other natural environments that allow exposure to the natural world. In the modern world it has begun to be known as Nature Therapy. It has been utilised and shown in both formal and informal programs to improve health, well-being, quality of life, mood and impact objective physiological measures of well-being including heart rate, blood pressure, salivary cortisol, natural killer cell count and alleviate disease states including depression, hypertension, diabetes, coronary artery disease, addiction, COPD and cancer.

Earthing

Different to Forest Bathing but certainly related is the practice of Earthing, also known as Grounding. It involves the contact of the skin (including but not limited to the soles of the feet) with the Earth, whether that be soil, sand, rock or grass and the Earth’s natural electrical conduction. The negative ions on the surface of the Earth are thought to be absorbed through the skin and used to neutralise free radicals in the body. Similar effects are seen when an Earthing pad is used that provides a similar effect to skin contact with the Earth when this is not possible (for example cold climates). The Earthing pad is commercially available and can be used during sleep or when seated.

Both practices can be utilised to improve health and well-being outcomes in both cancer and other chronic illness.

Mechanism of Action

Forest Bathing

A review of the literature by Hansen et al (2017) analysed over 70 publications on the beneficial effects of Shinrin-Yoku. Studies showed therapeutic effects on:

• immune system function: increased NK cells, cancer prevention

• cardiovascular system: improved cardiac function in coronary artery disease, improvement in blood pressure in both healthy individuals and in hypertension, improved blood glucose level in type 2 diabetes mellitus, increased oxyhaemoglobin levels

• respiratory system: improvements in allergies and respiratory illness such as COPD

• mood and stress: improved mood in anxiety and depression, reduced stress levels, enhanced feelings of relaxation, quality of life, sleep and overall perception of well-being

• mental relaxation: improvements in ADHD, addiction, including alcoholism

• human feelings of awe: enhanced gratitude, selflessness, sense of purpose and fulfillment

• autonomic nervous system: reduced prefrontal cortex activity

Criticisms of the included studies included small sample size, gender and age homogeneity and the possibility of priming bias (i.e an individual’s prior relationship with nature throughout their lifetime may influence the amplitude and frequency of physiological effects). However, overall, there was very encouraging evidence to consider implementing Forest Bathing or Nature Therapy into the care plan of patients with chronic illness, in healthy individuals for disease prevention and for overall enhancement of health and well-being. The positive results persisted when analysed for differences in culture, gender, education and marital status.

Earthing

A review article published by Menigoz et al in 2020 describes the myriad of health benefits posed by Earthing. Among them are reduced inflammation, pain, and stress, improved blood flow, energy, wound healing and sleep and a greater sense of well-being.

Earthing is thought to work by a variety of mechanisms, however the main is to restore our natural electrical connection to the Earth that has been lost over time because of human lifestyle. It corrects the “electron deficiency syndrome” that has occurred because we no longer walk barefoot outdoors and mostly wear shoes that prevent the conduction of the Earth’s natural charge through our bodies. The natural electrical charge of the Earth is negative and direct contact is thought to restore electrons into our body. These serve to neutralise free radicals that are natural by-products of the normal day-to-day cell reactions in our body that can strip away electrons from healthy tissues if not balanced and become responsible for inflammation and disease. It has also been shown to enhance circulation which aids in wound healing, skin repair and improving blood pressure and cardiovascular health.

Clinical Trials – Use in Cancer

Forest Bathing

A study published in 2013 by Nakau et al included 22 patients with breast or lung cancer who received an integrative care model in green space. The results showed significant differences in functional and spiritual well-being, improved quality of life and psychological state, reduced cancer-related fatigue and increased natural killer cell activity.

A study published in 2007 by Li et al included 12 healthy males aged 37 to 55 who received 3 days and 2 nights in a Forest Bathing trip. Serum levels of NK cells and the components of both NK cells and cytotoxic T lymphocytes were measured before and after the trip and after days 1 and 2. NK levels as well as anti-tumour enzymes were significantly increased after the trip compared with before and in greater levels on day 2 (after 2 days of forest bathing) compared with day 1.

Earthing

There are no clinical trials to date on the benefits of Earthing in specific cancer populations, however, the proven health benefits are directly related to minimising the risk of developing cancer through the reduction of risk factors such as chronic inflammation (Oschman et al 2015) and stress and enhancing immune function (Chevalier et al 2012).

Recommendations

Forest Bathing and Earthing have been demonstrated in clinical studies to enhance health and well-being in both healthy individuals and those affected by chronic illness including cancer. A minimum of 30 minutes daily is recommended, however any is better than none and the more the better.

References

1. Hansen MM, Jones R, Tocchini K. Shinrin-Yoku (Forest Bathing) and Nature Therapy: A State-of-the-Art Review. Int J Environ Res Public Health. 2017;14(8):851. Published 2017 Jul 28. doi:10.3390/ijerph14080851

2. Nakau M, Imanishi J, Imanishi J, et al. Spiritual care of cancer patients by integrated medicine in urban green space: a pilot study. Explore (NY). 2013;9(2):87-90. doi:10.1016/j.explore.2012.12.002

3. Li Q, Morimoto K, Nakadai A, et al. Forest bathing enhances human natural killer activity and expression of anti-cancer proteins. Int J Immunopathol Pharmacol. 2007;20(2 Suppl 2):3-8. doi:10.1177/03946320070200S202

4. Menigoz W, Latz TT, Ely RA, Kamei C, Melvin G, Sinatra D. Integrative and lifestyle medicine strategies should include Earthing (grounding): Review of research evidence and clinical observations. Explore (NY). 2020;16(3):152-160. doi:10.1016/j.explore.2019.10.005

5. Oschman JL, Chevalier G, Brown R. The effects of grounding (earthing) on inflammation, the immune response, wound healing, and prevention and treatment of chronic inflammatory and autoimmune diseases. J Inflamm Res. 2015;8:83-96. Published 2015 Mar 24. doi:10.2147/JIR.S69656

6. Chevalier G, Sinatra ST, Oschman JL, Sokal K, Sokal P. Earthing: health implications of reconnecting the human body to the Earth's surface electrons. J Environ Public Health. 2012;2012:291541. doi:10.1155/2012/291541

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