Effects of Plant-Emitted Monoterpenes on Anxiety Symptoms: A Propensity-Matched Observational Cohort Study

Assessing the Anxiolytic and Relaxation Effects of Cinnamomum camphora Essential Oil in University Students: A Comparative Study of EEG, Physiological Measures, and Psychological Responses

Background

Cinnamomum camphora is a commercially important tree species in China, and it's also a common native tree in the forests of southern China. However, literature on the impact of Cinnamomum camphora essential oil (CCEO) on human psychophysiological activity is scarce. Hence, the primary objective of this study was to examine the effect of exposure to CCEO on the functioning of the human autonomic nervous system, electroencephalographic (EEG) activity, and emotional state.

Methods

Forty-three healthy university students participated. The data collected included heart rate (HR), blood pressure (BP), pulse rate, blood oxygen saturation (SpO2), electroencephalographic (EEG) activity, and the results of the Profile of Mood States (POMS) test.

Results

A drop in diastolic pressure (DBP) and pulse rate was also noticed after participants inhaled CCEO. Furthermore, EEG studies have demonstrated notable reductions in absolute beta (AB), absolute gamma (AG), absolute high beta (AHB), and relative gamma (RG) power spectra during exposure to CCEO. Conversely, the relative theta (RT) and power spectra values showed a significant increase. Additionally, the finding from POMS indicated that the fragrance evoked positive emotions and suppressed negative feelings.

Conclusion

The results suggest that exposure to CCEO may promote mental and physical relaxation, facilitate cognitive processes such as memory and attention, and enhance mood states.

Biogenic volatile organic compounds in forest therapy base: A source of air pollutants or a healthcare function?

Air pollution poses a significant threat to public health, while biogenic volatile organic compounds (BVOCs) play a crucial role in both aspects. However, the unclear relationship between BVOCs and air pollutants in the under-canopy space limits the accuracy of air pollution control and the exploitation of forest healthcare functions. To clarify the variation of BVOCs in forest therapy bases, and their impacts on ozone (O3) and fine particulate matter (PM2.5) at nose height, total VOCs (TVOCs) in the forest were collected during typical sunny days, while air pollutants and meteorological factors were observed simultaneously. The results showed that the branch-level emissions of P. tabuliformis were dominated by healthcare-effective monoterpenoids, with only α-pinene having relative air concentrations of over 5 % in forest air samples. The correlation between concentrations of under-canopy TVOCs and emission rates of BVOCs from P. tabuliformis was weak (p > 0.09) in all seasons. However, the correlation between concentrations of TVOCs and the concentrations of O3 and PM2.5 showed clear seasonal differences. In spring, TVOCs only showed a significant negative correlation with PM2.5 in the forest (p < 0.01). In summer and autumn, TVOCs were significantly negatively correlated with both O3 (p < 0.001) and PM2.5 (p < 0.01). Specifically, the negative linear relationships were more pronounced for O3 and oxygenated VOCs in autumn (R2 = 0.40, p < 0.001) than for other relationships. The relationship between air pollutant concentrations inside and outside the forest also showed significant seasonal differences, generally characterized by a weaker correlation between them during seasons of strong emissions. Therefore, BVOCs in coniferous forests are health functions as they can provide healthcare effects and mitigate the concentration of air pollutants in the forest, and the establishment of forest therapy bases in rural areas with low NOx can be a sensible approach to promote good health, well-being, and sustainable development.

Impact of climate change on immune responses and barrier defense

Climate change is not just jeopardizing the health of our planet but is also increasingly affecting our immune health. There is an expanding body of evidence that climate-related exposures such as air pollution, heat, wildfires, extreme weather events, and biodiversity loss significantly disrupt the functioning of the human immune system. These exposures manifest in a broad range of stimuli, including antigens, allergens, heat stress, pollutants, microbiota changes, and other toxic substances. Such exposures pose a direct and indirect threat to our body's primary line of defense, the epithelial barrier, affecting its physical integrity and functional efficacy. Furthermore, these climate-related environmental stressors can hyperstimulate the innate immune system and influence adaptive immunity-notably, in terms of developing and preserving immune tolerance. The loss or failure of immune tolerance can instigate a wide spectrum of noncommunicable diseases such as autoimmune conditions, allergy, respiratory illnesses, metabolic diseases, obesity, and others. As new evidence unfolds, there is a need for additional research in climate change and immunology that covers diverse environments in different global settings and uses modern biologic and epidemiologic tools.

From biodiversity to nature deficiency in human health and disease

Nature (biodiversity) loss is the loss or decline of the state of nature taking place in the wider environment. We present a novel concept, nature deficiency, referring to nature loss in the human body influencing health. Humans are connected with the natural environment and its microbes and biogenic chemicals through eating (drinking), breathing, and touching. The mental and sociocultural links to the environment are also strong. With medical and ecological research and guidelines, the diagnosis, prevention, and treatment of nature deficiency may become part of the clinical practice. Nature prescription is likely to find plausible forms in patient care and inspire preventive actions at the society level. Health professionals are in a key position to integrate public health promotion and environmental care.

Demographic, Psychosocial, and Lifestyle-Related Characteristics of Forest Therapy Participants in Italy: A Multicenter Cross-Sectional Survey

This research aims to provide a comprehensive overview of the key demographic, psychosocial, and lifestyle-related characteristics of forest therapy participants in Italy. A survey was conducted among 1070 adults who had engaged in standardized forest therapy experiences between June 2021 and October 2022. The findings indicate that most forest therapy participants in Italy share certain distinctive traits. They are primarily female, aged between 45 and 54 years, employed, and unmarried. Moreover, they possess a high level of education, predominantly reside in urban areas, demonstrate a strong environmental awareness, maintain a nature-oriented attitude, and typically exhibit moderate levels of trait anxiety. Additionally, they tend to be nonsmokers, possess a healthy BMI within the normal range, and consume an adequate quantity of fruits and vegetables on a daily basis. However, it should be noted that their male counterparts tend to be overweight and exhibit poorer dietary habits. Irrespective of gender, approximately 40% of forest therapy participants in Italy live with a chronic disease that requires daily medicinal treatment. Subsequent research should investigate whether these characteristics hold true in different countries. Furthermore, exploring the potential effectiveness of health-promoting interventions integrated with forest therapy sessions could prove beneficial in addressing these specific issues among forest therapy participants. By doing so, such interventions have the potential to contribute significantly to public health promotion and overall community well-being.