By Mary Hearty
Growing evidence suggests that forests remain significant in improving human health as they provide ecosystem services such as food, fuelwood, medicinal plants, clean water and income, all of which indirectly impact human health.
It is with this reason that the 2023 World Forest Day marked on March 21, with the theme “Forests and Health”, calls for giving, not just taking because healthy forests bring healthy people.
The United Nations also affirm this, noting that forests purify the water, clean the air, capture carbon to fight climate change, provide food and life-saving medicines, and improve our well-being.
Consequently, forests reduce risks associated with some major non-communicable diseases (NCDs), especially for people residing in urban settings affected by such diseases.according to a report produced by the World Wildlife Fund on the Vitality of Forests to Public Health.
These illnesses include cardiovascular diseases, cancers, chronic respiratory diseases, diabetes, and mental health. They are considered the fastest-growing and largest health burden globally as they account for about 70% of deaths.
Although evidence related to the intersection of NCDs and forests is relatively nascent, a growing body of research suggests that exposure to forest environments can provide benefits that positively affect the body’s immune system, blood pressure, heart rate, blood glucose, and stress hormones.
Moreover, access to forests also contributes to increased physical activity, which is associated with obesity prevention and reduced stress levels, both of which are factors that are linked to reduced risk of NCDs.
Further, the drivers of climate change and air pollution, especially deforestation are intrinsically connected to the global burden of NCDs.
A systematic review of 25 studies examining health and/or well-being in natural versus synthetic environments suggests that natural environments might have a direct and positive impact on well-being but concluded that there is a need for additional research to better understand the public health implications
Also, forests clean air and water, and reduce the risks of infectious diseases and NCDs by filtering pollutants from the air linked to NCDs risks including heart disease, stroke, pulmonary disease, and lung cancer.
Additionally, forests help mitigate the health impacts of water pollution which is a key driver of infectious diarrheal diseases. This is by reducing soil erosion and sediment load, filtering pollutants from water, and reducing pollutant inputs associated with human land use.
With diarrheal diseases being a leading cause of mortality for children aged under 5 years, the contribution of forests to pollution reduction holds the potential to have an important impact on children’s immediate and lifetime health.
Forests also provide a natural environment for physical exercise and activity, which has well established benefits in terms of mental health and risk reduction for several other NCDs
Forests positively impact nutrition and food security, particularly for forest-dependent and adjacent Indigenous peoples and local communities, improving health outcomes.
The report states that for communities that rely on forests for food, including those with limited market access to purchase food and in times of conflict or severe food insecurity, forests can provide a critical safety net by supplying micronutrients and protein from wild sources, which is especially important for children.
They can also protect people from the harsh impacts of natural hazards, including flooding, landslides, avalanches, wildfires, storms, and heat, that contribute to human deaths, injury, and illness.
With climate change exacerbating many of these risks, a focus on the role that forests can play in resilience to natural hazards could offer life-saving solutions, the report reads.
The effects of climate warming can result in rural and industrial workers’ exposure to excessive heat, which has clear implications on their health and productivity.
Forests also mediate the emergence and spread of zoonotic infectious disease and are thereby the first line of defense against the emergence and spread of new infectious diseases.
Notably deforestation threatens this protective role as research on infectious diseases shows that deforestation can increase disease risk for humans by improving and altering the biology of disease vectors’ habitats.
Furthermore, deforestation and degradation of forests also amplify disease risk by increasing the chance of disease spillover from animals to humans due to closer contact; increasing the densities of disease host and vector populations; and decreasing the biodiversity that can help to dilute disease-vector infection rates.
