The environment we live in – and the quality of the air we breathe – can make a big difference to how we manage respiratory conditions like asthma and COPD. While medications and standard care remain the foundation of treatment, there’s increasing interest in how lifestyle changes and natural environments might help support lung health.
This article takes a balanced look at some of the emerging evidence around nature exposure, air quality, and environmental strategies, and offers practical ideas to support safer breathing and better wellbeing.
Green spaces and lung health
You might not associate leafy parks or tree-lined streets with lung health, but several studies suggest a possible link between greener environments and lower rates of asthma – especially in children. Researchers have explored a range of mechanisms, from reduced stress and better immune regulation, to lower pollution and increased physical activity.
Some observational studies, like a case-control study from Lithuania, have shown that children living near green spaces had a lower risk of developing asthma.
Other research from Canada has found that not just the amount, but the structure and type of green space may influence respiratory outcomes.
A 2022 review also found consistent associations between neighbourhood greenery and better respiratory health, although the exact causes remain hard to pin down.
We also are beginning to understand that being in nature helps lower stress hormones like cortisol, which is relevant because psychological stress has recognised impacts on both asthma and COPD symptoms.
It’s important to note that these studies can’t prove cause and effect. Other factors like socioeconomic status or access to healthcare could be involved.
Still, the evidence supports the idea that access to nearby natural spaces could be one part of a healthier environment for people with lung conditions.
You don’t need to trek into the wilderness – even short, regular walks in a nearby park can be enough to gain some benefit. If mobility is limited, just spending time sitting in a garden or courtyard with plants and natural views may also help reduce stress and promote calm breathing.
Forest bathing and nature immersion
The idea of “forest bathing” comes from Japan, where it’s known as Shinrin-yoku – a practice of mindfully immersing yourself in natural surroundings. It doesn’t involve exercise, just being present in a forest or woodland environment.
Some researchers have explored whether this kind of nature immersion can influence stress hormones, inflammation, or immune markers that relate to chronic conditions.
A recent randomised controlled trial explored this question by comparing people with COPD who took part in nature immersion activities in forest environments with those who spent the same time in urban settings. The researchers found that participants exposed to the forest environment had a significant reduction in pro-inflammatory markers like IL-6 and TNF-α, as well as improved respiratory symptoms and a better sense of wellbeing compared to the urban group.
What might explain these benefits?
It could be the combination of cleaner air, reduced noise, increased exposure to plant compounds called phytoncides, or simply the calming effect of being in a peaceful natural setting.
The activities also involved slow-paced walking and gentle movement, which support lung function without overexertion.
If access and mobility allow, finding local woodlands or quiet green trails could be a low-risk way to reduce stress, gently boost physical activity, and support respiratory health. The key is consistency – aim for short, regular visits and go at your own pace.
While early evidence is encouraging, most forest bathing studies are still small and context-specific. It’s best viewed as a complementary strategy, not a replacement for prescribed treatments or pulmonary rehabilitation. Always check with your clinician if you’re unsure what’s safe for you.
If you enjoy nature, try to incorporate it into your weekly routine in a way that fits your lifestyle. Whether that’s a mindful stroll in the woods, a picnic in a quiet meadow, or time spent tending plants on a balcony – the goal is to connect, not achieve a target.
Air pollution: A major risk factor
Air pollution is a well-established cause of asthma flare-ups, reduced lung growth, and COPD exacerbations. Exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone can inflame the airways and increase the risk of hospitalisation or poor control.
In the UK, estimates suggest up to 36,000 early deaths each year may be linked to air pollution. And people with pre-existing respiratory conditions are among the most vulnerable.
The challenge is that pollution levels vary day by day and hour by hour. Understanding how to interpret the Air Quality Index (AQI) or using apps like DEFRA’s UK-AIR can build your knowledge and confidence and help you make safer choices about when and where to go outside.
Planning walks during lower-pollution times (often early morning or after rain) may reduce your risk of symptoms.
Understanding Air quality
When we talk about air pollution and lung health, we often hear about three main pollutants:
Particulate Matter (PM2.5)
These are tiny particles in the air – 30 times smaller than the width of a human hair. They come from things like car exhausts, fires, factories, and even wood burners.
- Because they’re so small, PM2.5 can get deep into your lungs and even enter your bloodstream.
- Linked to asthma flare-ups, COPD symptoms, heart disease, and early death.
Think of PM2.5 as invisible dust floating in the air that your lungs can’t easily filter out.
Nitrogen Dioxide (NO₂)
This is a gas released when fuel is burned, especially by diesel cars, buses, and heating systems.
- It can irritate your lungs, making asthma and COPD symptoms worse.
- Long-term exposure can reduce lung growth in children and increase lung disease risks.
You’ll find more NO₂ near busy roads or in cities with lots of traffic.
Ozone (O₃)
This is a natural gas high up in the atmosphere that protects us from the sun – but at ground level, it’s a harmful pollutant.
- Formed when sunlight reacts with pollution from vehicles and industry.
- Can cause coughing, chest tightness, and trouble breathing, especially during hot, sunny weather.
Ozone is more likely to affect your breathing in summer or on high pollution days.
The Air Quality Index (AQI) is a simple way to understand how clean or polluted the air is – and what it means for your health. It gives a score from 0 to 500, with colour codes to show how safe it is to go outside.
Here’s a quick breakdown:
| AQI colour | Number range | What it means | Advice for people with asthma or COPD |
|---|---|---|---|
| 🟢 Green | 0-50 | Good air quality | Safe to be outside – enjoy your activities. |
| 🟡 Yellow | 51-100 | Moderate | Still safe for most, but if you’re sensitive, take it easy. |
| 🟠 Orange | 101-150 | Unhealthy for sensitive groups | You may notice symptoms. Consider reducing outdoor activity. |
| 🔴 Red | 151-200 | Unhealthy | Limit time outdoors, especially if exercising. Keep reliever inhaler handy. |
| 🟣 Purple | 201-300 | Very unhealthy | Stay indoors with windows closed. Use an air purifier if you have one. |
| 🟤 Maroon | 301+ | Hazardous | Avoid going outside. Follow your asthma/COPD action plan. Seek help if symptoms worsen. |
Air quality apps and tools
Recommended tools:
- DEFRA UK-AIR: Real-time pollution levels by postcode
- Plume Labs / AccuWeather: Free app showing hourly air quality forecasts
- IQAir Visual: Air pollution map with PM2.5 and pollen data
Avoid busy roads, check the Air Quality Index (AQI) on hot days, and try to spend time in clean-air environments like green spaces or forests.
Always check air quality before exercising outside, especially if you’re sensitive to pollution or pollen.
Indoor air quality
Many of us spend most of our time indoors – so it’s no surprise that indoor air quality matters. Triggers like tobacco smoke, damp and mould, volatile organic compounds (VOCs) from cleaning products, or dust mites can contribute to worsening symptoms.
NICE recommends improving ventilation, controlling allergens, and avoiding tobacco smoke as key steps to support people with asthma and other respiratory conditions.
Simple actions such as opening windows regularly, using extractor fans while cooking, reducing the use of chemical air fresheners or harsh cleaning products, and avoiding indoor smoking can make a meaningful difference to your lung health.
In the home, HEPA filters may help improve air quality for people with asthma, COPD, or allergies-especially in areas with poor ventilation or high pollution. HEPA stands for High Efficiency Particulate Air filter. It’s a type of air filter that can trap very small particles-including dust, pollen, mould spores, and even some bacteria and viruses-making the air cleaner and safer to breathe. To be called a HEPA filter, it must capture at least 99.97% of particles that are 0.3 microns in size, which are among the hardest to trap. These filters are commonly used in air purifiers, hospital settings, and even aircraft ventilation systems.
Evidence suggests they can help reduce the concentration of airborne particles and pollutants, including viruses, although further research is needed.
✅ What you can do:
- Keep your home well-ventilated (even just a 10-15 minute window open daily helps)
- Use extractor fans when cooking or showering
- Avoid indoor smoking
- Reduce use of strong-smelling sprays or cleaning agents
- Consider a HEPA air purifier in high-risk or poorly ventilated spaces
Think about small tweaks that feel achievable – like choosing fragrance-free cleaning products, ventilating after showers, or dusting with a damp cloth to trap allergens. These micro-changes, over time, can reduce your exposure and support long-term habits.
Open windows regularly, use extractor fans when cooking, and avoid indoor smoking. Consider HEPA filters in high-risk homes.
Occupational and environmental triggers
Some people’s asthma or COPD symptoms worsen due to exposure at work – whether from dust, fumes, allergens, or chemicals. This is known as occupational asthma or occupational COPD.
Estimates suggest that up to 15% of adult asthma cases could be work-related. Occupations such as cleaners, hairdressers, bakers, welders, and factory or healthcare workers may be more at risk.
If your symptoms seem worse during work days and improve on weekends or holidays, it’s worth discussing with your GP. An occupational health assessment may help identify and reduce exposure.
Improving your environment doesn’t always mean quitting your job – sometimes changes like better ventilation, protective equipment, or shifting duties can make a difference. Speak up and seek support if you think your workplace might be affecting your health.
Tell your GP if your symptoms are worse at work. You may be eligible for an occupational health referral.
Summary: What you can do
| Strategy | Benefit |
|---|---|
| Spend time in green or natural spaces | May reduce stress, inflammation, and improve quality of life |
| Avoid polluted areas and check air quality forecasts to guide outdoor activity | Reduces exposure to known respiratory irritants |
| Keep your home clean, dry, and well-ventilated | Helps control allergens, VOCs, and mould |
| Avoid smoking or second-hand smoke indoors | One of the most important changes for lung health |
| Use HEPA filters or air purifiers if needed | Especially useful in high-traffic areas or mould-prone homes |
| Seek advice for work-related exposures | Some people benefit from changes in environment or equipment |
You don’t have to overhaul your life to see benefits. Even small steps, taken regularly, can add up to better breathing and improved wellbeing.
If you haven’t already, download the free Evergreen Life app to track your health, including managing your asthma and/or COPD, and get practical tips that help you take control of your overall health.
This article is for informational and educational purposes only and does not replace medical advice or diagnosis from a qualified healthcare professional. While it draws from high-quality evidence on the potential benefits of nature exposure and environmental strategies for people with asthma or COPD, individual responses may vary, and these approaches are not substitutes for prescribed medications or medical care.
Nature-based therapies (e.g. time spent outdoors, forest bathing, green exercise) and environmental changes (e.g. improving air quality or avoiding pollution and allergens) can form part of a holistic, lifestyle-focused approach to respiratory health. However, they should always be used alongside (not instead of) established medical treatments and personalised care plans.
If you experience any of the following, seek medical advice promptly:
– Increased breathlessness or wheeze, especially when outdoors or near pollen, mould, or smoke
– Chest tightness, cough, or flare-up symptoms that aren’t improving
– Symptoms triggered by cold air, heat, damp, or environmental exposures
– Difficulty tolerating exercise or walking outdoors due to breathlessness
Avoid high-pollution areas or outdoor activity when local air quality is poor or pollen counts are high. You can monitor this using trusted sources like:
– UK Met Office Pollen Forecast
– DEFRA UK Air Quality Index
– Local environmental health websites or air quality apps (e.g. Plume Labs, IQAir)
🔴 Call 999 or seek emergency help if:
– You are struggling to breathe or speak in full sentences
– Your lips or fingers turn blue
– You feel drowsy or confused
– Your reliever inhaler is not helping during a flare-up
📞 Call NHS 111 or contact your GP if:
– Your symptoms are getting worse or more frequent
– You’re unsure how to manage your asthma or COPD outdoors
– You need help adjusting your medication plan to suit activity or environment
– You’re feeling anxious or low about symptom control or access to nature
Always speak to your healthcare team before making changes to your medication or activity level, especially if your condition is not well controlled or you’ve recently had an exacerbation.
- Alasauskas S, Ustinaviciene R, Kavaliauskas M. Residential Links to Air Pollution and School Children with Asthma in Vilnius (Population Study). Medicina (Kaunas). 2020 Jul 13;56(7):346. doi: 10.3390/medicina56070346. PMID: 32668717; PMCID: PMC7404686.
- BTS/Sign, (2019) British guideline on the management of asthma, Sign 158.
- Dong, Yuping & Liu, Helin & Zheng, Tianming. (2021). The Impacts of Green Space Structure on Asthma in Toronto, Canada. Medical Sciences Forum. 4. 9123. 10.3390/ECERPH-3-09123.
- Ewert A, Chang Y. Levels of Nature and Stress Response. Behav Sci (Basel). 2018 May 17;8(5):49. doi: 10.3390/bs8050049. PMID: 29772763; PMCID: PMC5981243.
- Gov UK. Health matters: air pollution. Gov.UK.
- Hartley, Kim & Ryan, Patrick & Brokamp, Cole & Gillespie, Gordon. (2020). Effect of greenness on asthma in children: A systematic review. Public Health Nursing. 37. 453-460. 10.1111/phn.12701.
- Li Q, Takayama N, Kimura Y, Takayama H, Kumeda S, Miura T, Kitagawa T, Aoyagi Y, Imai M. Forest bathing improves inflammatory markers, SpO2, and subjective symptoms related to chronic obstructive pulmonary disease (COPD) in male subjects at risk of developing COPD. J Occup Health. 2025 Jan 7;67(1):uiaf041. doi: 10.1093/joccuh/uiaf041. PMID: 40673365; PMCID: PMC12353587.
- Mansoor J, Zia Ul Haq M, Ahsan Z, Bilal M, Fatima SS. Effect of high-efficiency particulate air filter on children with asthma: a systematic review protocol of RCTs. BMJ Open. 2024 Dec 15;14(12):e087493. doi: 10.1136/bmjopen-2024-087493. PMID: 39675828; PMCID: PMC11647309.
- NICE (2019) Air pollution: outdoor air quality and health. NICE.
- NICE (2020) Indoor air quality at home. NICE.
- Noakes, C. and A. Beswick, (2023) How we know that HEPA filter based air cleaners are likely to be beneficial for reducing transmission of respiratory infections. Protect COVID-19 National Core Study.
