Forest air decreases anxiety. Experimental research conducted in 39 Italian sites between mountains, hills and urban parks has made it possible to reveal the role of monoterpenes, the fragrant components of essential oils emitted by plants, and to isolate their specific effect on the significant reduction of anxiety symptoms. The study was conducted by a team from the Institute for the bioeconomy of the National Research Council of Florence (Cnr-Ibe) and the Italian Alpine Club (Cai), together with the universities of Parma and Florence and the local health authority of Reggio Emilia. with the support of the Regional Reference Center for Phytotherapy (Cerfit) of Florence. The research is published in the ‘International Journal of Environmental Research and Public Health’.
Based on the analysis of environmental and psychometric data collected during the campaigns carried out in 2021 and 2022, the specific effect of exposure to monoterpenes (and in particular to alpha-pinene) on the significant reduction of anxiety symptoms, identifying not only exposure thresholds, but also the correlation to the amount of inhaled monoterpenes. “The results show that, beyond a given threshold concentration of total monoterpenes or even alpha-pinene alone, anxiety symptoms decrease regardless of all other parameters, both environmental and individual. And since these compounds are emitted by plants, we can now assign a specific therapeutic value to each green site, also conditioned by attendance at different times of the year and day”, underlines Francesco Meneguzzo, Cnr-Ibe researcher and member of the central scientific committee of the CAI.
“Monoterpenes – he adds – are much more abundant in remote forests than in urban parks, albeit with a considerable degree of variability: a next step will be to map and predict the relative concentrations”.
The organization of the research proved to be particularly articulated, with hundreds of participants involved in standardized therapy sessions, conducted in sites throughout Italy, explains a note. “By combining forest therapy sessions conducted by professional psychologists with advanced statistical techniques, we were able to demonstrate that, under certain conditions, the forest air is indeed therapeutic: an important milestone for the progressive adoption of green health practices,” says Federica Zabini of Cnr-Ibe, Cnr project manager and research supervisor.
“We have applied an advanced statistical method used in clinical research, which has made it possible to create perfectly matched intervention and control groups: the results now allow us to have objective criteria for identifying and qualifying forest therapy stations capable of allow clinical level services – highlights Davide Donelli, of the Department of Medicine and Surgery of the University of Parma and of the Cardiology Division of the Parma University Hospital – Since the connection between states of anxiety and cardiovascular risk is now consolidated, the results obtained assume an important value also in the pathophysiological field, and that will be the subject of further research”.
The study continues the line of research undertaken in 2019 relating to the distribution of essential oils emitted by plants, which has led to numerous scientific publications and the creation of two volumes on forest therapy, published by the Cnr, which have made it possible to systematize the knowledge to date knowledge about this emerging discipline.