Immunostimulant Effect from Phytoncide of Forest Bathing to Prevent the Development of Cancer

Forest bathing is a visit to forest leisurely for health benefit, the researcher has revealed that forest bathing has cancer preventive effect. This review highlights recent evidence about phytoncide of forest bathing that can prevent cancer development by increasing activity and number of natural killer (NK) cells. The studies were conducted by literature research from a journal published in PubMed and ScienceDirect database from 2007 to 2017 by using the keywords of “forest bathing,” along with “NK activity” or “stress” or “heart rate.” Many studies reported that forest bathing significantly reduced the stress and increased the number of natural killer (NK) cell that can kill the tumor cell. There is a compound group in the forest air called phytoncides such as α-pinene and limonene, which is available in the forest, but not in the city. Phytoncide groups from the forest give relaxation effect, reducing stress hormone release which can decrease the amount of T-cells level; it also increases NK cell amount that can kill tumor cell by releasing the anti-cancer protein. Immunostimulant effect of forest bathing last more than 30 days. By visiting forest once in a month that release phytoncides from the trees can decrease the stress hormone and increase the number of NK cells, which can prevent the development of cancer generation and development. Furthermore, this forest bathing can be the solution for stress management and prevent the development of disease, such as cancer.