Human Health Impacts and How to Fight Back

Aside from making great material for nature docuseries like Planet Earth, forests play an essential role in maintaining balance in the natural world: human and otherwise.

For instance, forests perform important functions like:

  • regulating weather conditions
  • reducing carbon dioxide (CO2) in the atmosphere
  • maintaining biodiversity
  • ensuring food security
  • redistributing water to dry regions
  • preventing natural disasters and flooding
  • preventing fires and air pollution
  • providing shelter and food to billions of people (not to mention animals and plants)
  • supporting mental health

Reducing atmospheric carbon dioxide

According to a 2017 review, trees are responsible for removing carbon from the atmosphere and storing it underground. Known as “carbon sinks,” these banks of CO2 reduce greenhouse gases and lessen the effects of climate change.

Worldwide tropical forests are responsible for storing 25 percent of the world’s carbon.

According to a 2019 study, U.S. temperate and boreal forests alone remove enough atmospheric CO2 to reduce national annual net emissions by 11 percent.

Keeping the Earth cool

The same review notes that trees can actually help keep conditions on the ground cooler and wetter.

Trees naturally absorb and redistribute the sun’s energy, helping to keep temperatures down. They draw water out of the soil and exhale it into the atmosphere, impacting the balance of water and heat on Earth’s surface.

Of course, trees also provide shade, further preventing soils from drying out and eroding.

Distributing and storing water

Tropical forests play an important role in the water cycle by returning around 90 percent of precipitation into the atmosphere in the form of water vapors. That water vapor is responsible for rainfall.

Forests also encourage the transport of moisture through the atmosphere, redistributing water to regions that are prone to drought.

Trees filter water into the soil and prevent runoff. They also improve groundwater recharge, which means they increase the amount of water stored underground in water tables.

Providing homes to people and wildlife

According to a 2017 study, forests are the most diverse and highly productive ecosystems on earth, providing a home to thousands of local, rare, endangered, and threatened wildlife species.

These species play a significant role in ecosystem functions like:

  • pest control
  • pollination
  • seed dispersal

A 2020 study found that 1.93 billion people lived within 6.2 miles (10 km) of a forest as of 2012, with 1.6 billion people depending on those forests for their livelihoods.

The five countries with the highest rates of people living near forests are:

  • China
  • United States
  • Indonesia
  • India
  • Brazil

Ensuring global food security

Tropical forests also make a major contribution to food security, or the availability and accessibility of food.

Roughly one-third of the food supply and global crops depend on wild pollinators that make their homes in forests.

Forested soils are typically richer in organic matter and more resistant to erosion and extreme weather. The lack of healthy, nutritious soil can lead to low yields and food insecurity.

Protecting against flooding and natural disaster

Deforestation weakens and degrades the soil, making the land vulnerable to landslides and floods.

Forests also increase the life span of dams by reducing sediments into rivers, mitigate disasters by reducing soil erosion and landslides, and reduce the intensity and severity of floods.

A 2013 United Nations Environment Programme Report noted that the flooding from 2004 tropical storm Jeanne, which killed more than 3,000 people in Haiti, was due to the removal of 98 percent of the nation’s forests.

The storm set off widespread flooding and mudslides, washing away whole villages due to the lack of trees and topsoil that would normally reabsorb water into the ground.

Reducing rates of infectious diseases

According to a 2021 report from the Harvard Global Health Institute, land-use change is a primary culprit for diseases transmitted from animals to humans, known as zoonotic diseases.

Furthermore, a 2019 case study in Indonesia solidified the connection between malaria and deforestation when it found that just a 1 percent loss in forest cover increased malaria incidence by 10 percent.

“Displaced animals in deforested regions may be infected with pathogenic viruses, bacteria, or fungi,” explains Oladele A. Ogunseitan, University of California Presidential Chair and professor of Population Health & Disease Prevention. “When these animals seek shelter or food in human habitats, pathogen spillover events can occur, leading to human infection.”

According to a 2020 report by the World Economic Forum, 1 in every 3 or 31 percent of outbreaks of new and emerging diseases, such as Zika, Ebola, and Nipah, are linked to deforestation.

In addition, the report notes that climate change is leading to changes in transmission patterns of infectious disease, potentially accelerating outbreaks of Zika, Malaria, and Dengue Fever.

“New outbreaks are certain to occur,” the report states.

Deforestation and COVID-19

The COVID-19 pandemic may be the first outbreak to bring widespread attention to the issue of deforestation, though it certainly wasn’t the first to be affected by it.

According to a 2020 study, the pandemic has brought new urgency to the importance of tropical forest conservation, stating that “tropical deforestation increases the risks of emerging zoonotic diseases with pandemic potential.”

Interestingly, Ogunseitan notes that deforestation may be “part of the reason we now see COVID-19 in deer populations in the U.S.

Preventing fires and protecting air quality

It turns out those first graders know what they’re talking about: healthy forests lead to healthy air to breathe.

This is not only because they convert CO2 to oxygen, but because deforestation can lead to fires due to increased dryness in soil, plants, and brush.

A 2019 Brazilian report found that deforestation-related fires were associated with a significant impact on public health. In the findings, 2,195 subsequent hospitalizations were due to respiratory illnesses.

Official air quality data found that in 2019, nearly 3 million people in this region had exposure to harmful levels of fine particulate matter (PM 2.5), a pollutant that results in hazy air.

This pollutant is strongly correlated with Amazon fires as well as respiratory disease, cardiovascular disease, and premature death.

A 2021 study of 450 fires in California’s Sierra Nevada region found that a 1°C/33.8°F increase in temperature equates to a 19 to 22 percent increase in the likelihood of fires.

As forests are cleared, temperatures will continue to rise, likely leading to more forests going up in flames.

Supporting Indigenous culture and underserved communities

Climate change disproportionately affects Black, Indigenous, and People of Color (BIPOC).

Indigenous people in the Amazon feel the impact of deforestation acutely.

Illegal cutting and resulting fires often occur in or near Indigenous territories, destroying crops and depleting the area’s plants and wildlife used for food and medicine.

This can lead to Indigenous peoples being displaced, scattered, and struggling to survive.

Supporting mental health

Forests also play an important role in mental health.

According to a 2019 study, spending just 2 hours in nature a week is enough to produce benefits for mental and physical health and well-being.

Another 2019 scientific review found that time in a natural environment benefits emotional well-being in a number of ways, including:

  • increased positive emotions
  • a greater sense of meaning and purpose
  • increased positive social interactions
  • fewer incidences of mental distress

“Shinrin-yoku” is the Japanese art of forest bathing, or spending time in the forest with the sole purpose of soaking up its calming, rejuvenating effect.

A 2020 review and meta-analysis noted that Shinrin-yoku was effective at reducing short-term mental health symptoms, particularly anxiety.

This practice falls under the umbrella of ecotherapy, an approach based on the idea that people have a deep connection to the environment and the earth itself.

Individuals can do what they can to support the world’s forests by making lifestyle changes and spreading awareness.

Eat less meat

The Harvard Global Health Institute cautions that current agricultural practices put our forests and human health at risk.

Additionally, the 2019 United Nations Special Report on Climate Change and Land notes that shifting to a plant-based diet is an opportunity to mitigate climate change.

Be aware of palm oil in the foods you buy

The production of palm oil, which shows up in many processed and manufactured foods, is a significant culprit in deforestation.

According to a 2018 report, palm oil demand is expected to increase by about 40 percent by 2030.

The Round Table on Sustainable Palm Oil notes that as of 2022, only 19 percent of palm oil is certified sustainable.

You can make an effort to reduce or eliminate processed foods or switch to companies using certified sustainable palm oil.

Recycle and reuse before purchasing new

Mining is another reason for deforestation. Mining occurs to extract raw materials from the earth, such as:

  • silicon
  • aluminum
  • copper
  • lead
  • gold

These are used for products like electronics.

Consider using items as long as possible rather than trading up for the next model. If you need something replaced, consider buying used.

You’ll not only be reducing your impact on the environment, but you’ll likely save some money in the process.

Spread awareness and call for change

Recognizing and understanding the connection between forests and human health is a huge first step.

You can also support government initiatives by raising awareness, contacting local officials, and donating or getting involved with nonprofit organizations.

Support government protections

In the Brazilian Amazon, deforestation rates fell approximately 70 percent between 2005 and 2012 due to public policies and public and private actions. While it’s clear that change can have a positive impact, 2020 saw decade-high levels of deforestation due to a change in government.

Scientists recommend that at least 50 percent of land and oceans be protected and maintained as intact natural ecosystems.

While some private companies have committed to better practices, governments are likely the ones that need to step in and enact protections.

In 2020, seven countries reported decreased deforestation partially accomplished due to implementing and enforcing stronger regulations.

Support Indigenous rights and responsible land use

Restoring land rights to Indigenous peoples is a necessary step government can take.

A 2018 study on Brazilian deforestation rates found a two-thirds decrease in areas where Indigenous people owned their lands.

A 2017 study on Peruvian forests found that redistributing land use and management to Indigenous people led to a 71 percent average yearly decrease in deforestation and forest disturbance.

The 2021 study mentioned above notes that Indigenous Americans took responsibility for fire management in western North America prior to colonization, resulting in frequent, small fires that enhanced ecosystems and resource gathering.

After Spanish, Mexican, and U.S. settlement, many Indigenous peoples were lost and livestock often took precedence over forests.

Be aware of infectious disease trends

Knowing what pathogens may be an issue could also help lessen the spread of diseases or get ahead of the curve.

Forests play an essential and undeniable role in the planet’s life cycle and human health.

From reducing rates of infectious diseases to protecting against food insecurity, forests are an integral part of the web of life on Earth.

While deforestation is a direct threat to human and environmental health, there are ways to shift the tides, including improving eating and shopping habits, encouraging government action, and granting more rights to Indigenous people.

We’re all in this together, and we have the power to make deforestation a thing of the past.


Crystal Hoshaw is a mother, writer, and longtime yoga practitioner. She has taught in private studios, gyms, and in one-on-one settings in Los Angeles, Thailand, and the San Francisco Bay Area. She shares mindful strategies for self-care through online courses. You can find her on Instagram.


Ashley Hubbard is a freelance writer based in Nashville, Tennessee, focusing on sustainability, travel, veganism, mental health, social justice, and more. Passionate about animal rights, sustainable travel, and social impact, she seeks out ethical experiences whether at home or on the road. Visit her website wild-hearted.com.