A Reason to Preserve Environment More: Smells of Nature May Benefit Our Health

We’ve been told many, many times of this good old advice: spending time in nature is good for our overall health.

A lot of studies have shown how contact with nature can increase our well-being by affecting emotions, reducing stress, influencing thoughts, and improving physical health.

And it doesn’t have to be a two-hour walk or something–a brief exposure to nature can also help. A popular study found that hospital patients recovered faster if their room included a window view of a natural setting.

Now, understanding deeper about nature’s effects on our bodies won’t only help our health further. It could also strengthen our awareness and knowledge on how to care for land, preserve ecosystems, and design cities, homes, and parks.

To this day, however, studies on benefits of being out and about in nature have mostly focused on the eyes; how seeing nature affects us. The nose hasn’t received enough attention.

Because now that I think of it, I like the rain, but I like petrichor more than the rain.

And that’s why a group of researchers wants this to change.

One of the researchers, Gregory Bratman at the University of Washington, stated how we are actually surrounded by odorants and that we have a sophisticated olfactory system that processes them, which results in change of emotions and behavior.

“But compared to research on the benefits of seeing nature, we don’t know nearly as much about how the impacts of nature’s scents and olfactory cues affect us,” Bratman said.

The researchers have published their study in Science Advances. Here, Bratman and colleagues from around the world outline ways to expand research into how scents and odors from natural settings impact our well-being.

The group comprises experts in olfaction, psychology, ecology, public health, atmospheric science and other fields. They are based at institutions in the U.S., the U.K., Taiwan, Germany, Poland and Cyprus.

Humans and smelling capability

Olfaction, or the human sense of smell, is a complex system constantly at work.

Our noses contain hundreds of olfactory receptors that act as sophisticated chemical sensors, capable of detecting over one trillion scents.

This information is sent directly to the nervous system for interpretation, whether we’re aware of it or not.

On the other hand, the natural world continuously emits chemical compounds that keep our olfactory system busy.

Plants, in particular, release volatile organic compounds (VOCs) that can linger in the air for hours or even days.

VOCs help plants by repelling herbivores or attracting pollinators. Some researchers have studied how exposure to plant VOCs affects humans.

Bratman said, “We know bits and pieces of the overall picture. But there is so much more to learn. We are proposing a framework, informed by important research from many others, on how to investigate the intimate links between olfaction, nature and human well-being.”

According to the researchers, nature’s smell-related impacts likely happen through various pathways. Some chemical compounds, including certain plant VOCs, may influence us without our conscious awareness.

In these cases, olfactory receptors in the nose may trigger a “subthreshold” response to molecules that we humans are mostly unaware of.

Bratman and his co-authors are calling for extensive research on when, where, and how these undetected biochemical processes related to natural VOCs might affect us.

In general, we can detect some smells consciously. But scientists still don’t fully understand how they impact our health and well-being.

Smells, memory, culture

Certain scents, like a sweet-smelling flower, may be universally pleasant. However, some others are tied to specific memories or have associations that vary by culture and personal experience.

Bratman added, “Understanding how olfaction mediates our relationships with the natural world and the benefits we receive from it are multi-disciplinary undertakings.

“It involves insights from olfactory function research, Indigenous knowledge, Western psychology, anthropology, atmospheric chemistry, forest ecology, Shinrin-yoku — or ‘forest bathing’ — neuroscience, and more.”

Research into the links between our sense of smell and positive experiences with nature includes work by co-author Cecilia Bembibre at University College London. Her studies show that the cultural significance of smells, including those from nature, can be passed down through generations.

Co-author Jieling Xiao at Birmingham City University has explored the associations people have with scents in urban environments and gardens.

Other researchers have shown that nature leaves its signature in the air we breathe. Forests, for example, release a complex mix of chemicals into the atmosphere.

Research by co-author Jonathan Williams at the Max Planck Institute for Chemistry and the Cyprus Institute demonstrates how natural VOCs can react and mix in the air, affecting our olfactory environment.

Urging for more research

The authors are calling for more studies on how human activities alter nature’s scent profile. Pollution can change or eliminate these natural odors, and habitat loss reduces the sources of beneficial scents.

“Human activity is changing the environment so rapidly that we’re discovering these benefits even as they become harder to access.

“As research illuminates more of these links, our hope is that we can make more informed decisions about our impacts on the natural world and the volatile organic compounds that come from it.

As we say in the paper, we live within the chemical contexts that nature creates. Understanding this more can contribute to human well-being and advance efforts to protect the natural world,” Bratman said.

In my personal opinion, this is a call for us all to keep preserving the environment. While the researchers haven’t found out exactly how smelling nature affects our health and well being, the benefits of seeing and smelling nature are there.

And I also think that this is an encouragement to go outdoors more and stay connected with nature.

Some tips before you explore the outdoors

During the holiday month, it’s tempting to go into the woods on a whim because we have the time. But before you go, check if the trail that you’re going is in good condition; choose one that’s suitable for summer (or the current season in your country) as well as the weather.

Before setting off on a walk or hike, remember to check the day’s weather. This way, you can prepare properly, decide what to bring, and adjust plans if needed.

If rain is in the forecast for the mountains, consider staying at a lower altitude. In the desert on a hot day, carry extra water, sun protection, and stay close to the car park.

Always carry a rain jacket, sunscreen, a hat, and enough water, no matter the weather. In winter, dress in layers (in the right fabric) to adjust to changing temperatures.

Moreover, consider the time of the year. For example, in spring, just because there’s no snow in town doesn’t mean it’s melted at higher elevations. Some trails take months to clear after a long winter or wet season.

But whenever you’re unsure, always check with a park ranger or local expert. Then, you’re good to go and see and smell nature.

Sources

https://www.washington.edu/news/2024/05/15/nature-olfaction