Forest Bathing for Forest Bathing

Overseen By Gregory Bratman, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Washington

Must not be taking: Some types of medication

Disqualifiers: Pregnancy, Neurologic, Hypertensive, Psychiatric, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

Duration: 16 days

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how terpenes, natural compounds in forest air, contribute to the stress-relieving benefits of forest bathing (a therapeutic practice involving immersion in a forest environment). Participants will experience two scenarios: one with terpene exposure and one without. The trial is designed for non-smokers who can walk for 15-20 minutes and have no history of specific medical conditions. The study will help determine if terpenes play a key role in reducing stress during forest bathing. As an unphased trial, it offers participants the chance to contribute to groundbreaking research on natural stress relief methods.

Will I have to stop taking my current medications?

The trial does not clearly specify if you need to stop taking your current medications, but it does exclude people taking some types of medication. It's best to discuss your specific medications with the study staff.

What prior data suggests that this forest bathing intervention is safe?

Research shows that spending time in the forest, known as forest bathing, can offer health benefits. This includes exposure to natural substances called terpenes, found in trees, which give the forest its distinctive smell. Studies suggest that terpenes might help lower stress and boost the immune system. Specifically, research has found that terpenes can increase immune cells like NK cells and T-cells, which help fight infections.

Regarding safety, while these findings are encouraging, they don't specifically mention any negative effects. As this trial is in the early stages, detailed safety information might be limited. However, using forest environments for health benefits, even for children with asthma, suggests it is generally well-tolerated. Overall, while more research is needed on possible negative effects, forest bathing with terpenes seems to be a safe and natural way to reduce stress. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores the potential health benefits of forest bathing, which is the practice of immersing oneself in a forest environment. Unlike conventional treatments that might involve medication or therapy sessions in clinical settings, this approach leverages the natural environment and the inhalation of terpenes, aromatic compounds found in trees, which might offer unique therapeutic effects. The trial compares two methods: one where participants experience the full spectrum of forest air, including terpenes, and another where terpenes are filtered out. This investigation could reveal whether the presence of terpenes significantly enhances the mental and physical benefits associated with spending time in nature.

What evidence suggests that this forest bathing intervention could be effective for stress reduction?

Research has shown that terpenes, natural substances found in forests, might help reduce stress. These substances lower inflammation and lift mood, potentially lessening anxiety and improving overall well-being. Studies have also demonstrated that spending time in nature, known as forest bathing, can increase energy and reduce anxiety. This trial will compare two approaches: one where participants experience forest bathing with terpenes present in the air ("terpenes on") and another where terpenes are filtered out ("terpenes off"). Researchers believe that terpenes in the forest air enhance these positive effects. Evidence suggests that forest bathing with terpene exposure might help lower stress and improve mood. ^{1 2 3 6 7}

Who Is on the Research Team?

Gregory Bratman, PhD

Principal Investigator

University of Washington

Are You a Good Fit for This Trial?

Inclusion Criteria

Study staff will also use the clinically-validated UPSIT® test kit (Sensonics International, Haddon Heights, NJ) to evaluate olfactory sensitivity and identify/exclude participants with undiagnosed smell loss

Physically capable of walking for approximately 15-20 min from the study vehicle to the clinic and experimental locations

participants will complete a baseline survey on demographics, personality traits, and regular nature contact and perceptions

Exclusion Criteria

You currently have or had a diagnosis of a medical condition affecting the brain, high blood pressure, mental health, breathing, or loss of smell.

You are taking certain medications.

You are pregnant.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo two forest bathing sessions with and without terpene exposure, separated by a washout period of at least 8 days

16 days

2 visits (in-person)

Follow-up

Participants are monitored for changes in heart rate variability, blood pressure, and other physiological and psychological outcomes

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Forest Bathing

How Is the Trial Designed?

Group I: Terpenes On Experimental Treatment 1 Intervention

Forest bathing intervention with no filtration of terpenes from inhaled air using PAPR with particle-only filter ("terpenes on")

Group II: Terpenes Off Active Control 1 Intervention

Forest bathing intervention with filtration of terpenes from inhaled air using PAPR with activated charcoal filter ("terpenes off")

Who Is Running the Clinical Trial?

University of Washington

Lead Sponsor

Trials

1,858

Recruited

2,023,000+

National Center for Complementary and Integrative Health (NCCIH)

Collaborator

Trials

886

Recruited

677,000+

Published Research Related to This Trial

The Canadian adverse event reporting system for herbal products is severely underreported, leading to a lack of safety data, which poses risks to consumers who often perceive these products as safe.

Health food store personnel in the Greater Toronto Area play a crucial role in reporting adverse reactions by collecting customer information during product returns, suggesting a potential pathway to improve safety monitoring and reporting for herbal products.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Adverse event reporting for herbal medicines: a result of market forces. Walji, R., Boon, H., Barnes, J., et al.[2021]

A new adverse events (AEs) reporting form specifically designed for Korean folk medicine has been developed, incorporating unique characteristics such as folk medicine properties and patient information.

This reporting form is the first of its kind and aims to improve the tracking and understanding of adverse events related to Korean folk medicine, enhancing safety and efficacy monitoring.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Development of an adverse events reporting form for Korean folk medicine. Park, JH., Choi, SM., Moon, S., et al.[2021]

In a study involving 1118 patients across 10 community pharmacies, it was found that 58.8% of patients were using both prescription drugs and natural health products (NHPs) concurrently, which significantly increased their risk of experiencing adverse events (AEs).

Patients using both prescription drugs and NHPs were 6.4 times more likely to report an AE compared to those using only prescription drugs, highlighting the importance of monitoring concurrent use for safety.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pharmacy study of natural health product adverse reactions (SONAR): a cross-sectional study using active surveillance in community pharmacies to detect adverse events associated with natural health products and assess causality. Necyk, C., Tsuyuki, RT., Boon, H., et al.[2022]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5402865/

Terpenes from Forests and Human Health - PMC This review categorizes various terpenes easily obtained from forests according to their anti-inflammatory, anti-tumorigenic, or neuroprotective activities.

2. sciencedirect.com sciencedirect.com/science/article/pii/S0013935125007339

Forest terpenes and stress: Examining the associations of ... This body of research posits that the effects of forest bathing may be due in part to anti-inflammatory, psychoneuroimmunological processes ...

3. cdn.clinicaltrials.gov cdn.clinicaltrials.gov/large-docs/97/NCT05316597/Prot_000.pdf

Do Terpenes Play a Role in the Stress-reducing Effects of a ... Shinrin-yoku, also known as “forest bathing”, is a specific set of human-nature interactions that have been shown to improve mood, reduce anxiety and depressive ...

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC2793341/

Effect of forest bathing trips on human immune function In addition, in studies using the POMS test, forest bathing trips were found to significantly increase the score for vigor and decrease the scores for anxiety, ...

5. link.springer.com link.springer.com/article/10.5487/TR.2017.33.2.097

Terpenes from Forests and Human Health In conclusion, the studies that show the biological effectiveness of terpenes support the benefits of forest bathing and propose a potential use of terpenes as ...

6. sciencedirect.com sciencedirect.com/science/article/pii/S2950199724000491

Phytoncides and immunity from forest to facility This review found favourable immunological outcomes of phytoncide treatment, including increases in NK cells, T-cells, and cytotoxic effector molecules.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9104620/

Developing Forest Therapy Programmes Based on the ... Major detected terpenes were α-cadinol and spathulenol previously described as antiviral, antitumor, antimicrobial and immunomodulatory agents.