Would you believe me if I told you that just being surrounded by trees in the bush or a forest is good for your health? If you do nothing else but breathe the air in such places, you’ll get a boost to your immune system that can last up to 30 days (Li, 2019 p 78.) Amazing!
So what’s special about air in heavily treed places? The presence of phytoncides. If you haven’t heard of phytoncides you’re not alone - they’re a relatively new discovery sparking much interest from researchers in the field of Forest Medicine.
In a nutshell, phytoncides are chemical substances emitted by trees as part of their defence mechanism against bacteria, fungi and insects. They often have an aroma - think of that ‘pine smell’ when walking in a pine forest - that’s the aroma of alpha-pinene phytoncide. They have anti-bacterial, anti-fungal, anti-inflammatory, anti-microbial and anti-viral properties (Wang, 2019 p. 146.)
We don’t yet understand how or why it happens, but purely inhaling air rich in phytoncides has an effect on tumor and cancer fighting blood cells in our bodies, called ‘natural killer cells.’ When we inhale phytoncides, our bodies do 2 things - they produce more natural killer cells, and there’s a surge in activity amongst the natural killer cells that we already have. This means that our immune system is more effective (Li et al., 2008.)
Inhaling phytoncides also effects our blood pressure and heart rate - research in Taiwan found that participants' systolic blood pressure and heart rate decreased after inhaling phytoncides from conifer trees (Wang, 2019 p. 145.)
So next time you’re out and surrounded by trees, know that just simply breathing the air in that place is having a positive impact on your immune system, blood pressure and heart rate.
I wonder what else we’re receiving from the web of life surrounding us without even knowing it?
Li, Q. 2019 'Effect of Forest Therapy on Immune Function' in D. Kotte, Q. Li, W. Sop Shin and A. Michalsen (eds) International Handbook of Forest Therapy, Cambridge Scholars Publishing, UK, pp. 74-90.
Li, Q., et al., 2008 'A forest bathing trip increases human natural killer activity and expression of anti-cancer proteins in female subjects' J Biol Regul Homeost Agents Jan-Mar;22(1):45-55.
Wang, S. 2019 'The Effect of Phytoncides' in D. Kotte, Q. Li, W. Sop Shin and A. Michalsen (eds) International Handbook of Forest Therapy, Cambridge Scholars Publishing, UK, pp. 140-147.