Microbes, biodiversity and the benefits of getting dirty

We’re surrounded by life, but Earth’s most plentiful living things are invisible to the naked eye.

By David Suzuki

We’re surrounded by life, but Earth’s most plentiful living things are invisible to the naked eye. Microbes are not only around us, they live on and in us. Although some cause maladies ranging from food poisoning to smallpox, there are many we couldn’t live without.

Beneficial microbes break down food and produce vitamins in our guts. They coat our skin, protecting us from attacks by harmful microbes. Outside our bodies, they decompose organic waste, fix nitrogen and produce half the world’s oxygen.

Scientists refer to the microbial communities on and in our bodies as “microbiomes”. Every one of us hosts as many as 100 trillion microbes — our guts alone are home to 500 to 1,000 different bacteria species!

Just as human activity is harming the diversity of visible life, it’s also diminishing microbial diversity. As researchers learn more about the profound ways good microbes keep people healthy, they’re also seeing how our urbanized, indoor lifestyles have transformed our microbiomes, increasing the risk of disease.

Just as we pollute the environment outside us, we can also pollute and upset the “normal flora” of our bodies by what we eat and do. Effects range from indigestion to deadly disease. One modern consequence of our lack of understanding about the necessity of healthy microbiomes is seen in our use of antibiotics. Despite their benefits, decades of overuse for personal sanitation, minor maladies and to promote growth in livestock has led to new illnesses and infections as sometimes-harmful bacteria evolve to resist antibiotics and our own microbial defences.

According to Alan Logan, author of Your Brain on Nature, diet and where we live and play have a tremendous influence on the microbial ecosystems on our skin and in our noses, mouths and intestines. Logan and experts from a range of disciplines at the Natural Environments Initiative workshop at Harvard School of Public Health found people who live in areas with rich plant diversity have more diverse microbiomes. The air we breathe, the soil we dig and the outdoor plants we come into contact with include a variety of microbes that may be absent in indoor and built environments.

Researchers have even found digging in dirt, whether gardening or playing, can benefit our physical and mental health. A microbe common to mud and wet soils, Mycobacterium vaccae, has been shown to influence brain neurotransmitters to reduce anxiety and improve cognitive functioning. Another microbe encountered in natural environments, Acinetobacter lwoffii, has been shown to benefit the human immune system, preventing asthma, hay fever and other ailments in children who have been exposed to it — although it can also cause infections and gastric problems for people with compromised immune systems.

Research by Ilkka Hanski and colleagues at the University of Helsinki found microbe diversity reduced the incidence of allergies. They compared adolescents living in houses surrounded by biodiverse natural areas to those living in landscapes of lawns and concrete. From skin swabs, they learned that higher native plant diversity appears to be associated with greater and more diverse microbial composition on the participants’ skin, which led to lower risk of a range of allergies.

It’s likely that, as we learn more about the microbial world, we’ll find other beneficial microbes in nature. The research also highlights the importance of overall biodiversity to human health. A good solution to protecting biodiversity, from the smallest microbe to the largest animal, and to keeping ourselves healthy, is for all of us to spend more time outside.

According to the American Public Health Association, “People of all ages and abilities enjoy higher levels of health and well-being when they have nature nearby in parks, gardens, greenways, naturalized schoolyards and playgrounds, and natural landscaping around homes and workplaces.”

People responding to David Suzuki Foundation surveys after our annual 30X30 Nature Challenge report significant mood improvements, more vitality and energy, and increases in nature-specific emotions like awe, curiosity and fascination. Research has also shown people who develop deeper connections with nature are more likely to care for and protect it, a phenomenon renowned biologist E.O. Wilson called “biophilia.”

As this year’s 30X30 Nature Challenge wraps up, consider it an inspiration to get outside every day of the year. It’s good for your health, mood and microbiome — and nature!

Written with contributions from David Suzuki Foundation senior editor Ian Hanington.

Learn more at www.davidsuzuki.org

Just Posted

Old-growth logging protesters block a road on Monday, June 14. This is not the blockade at Honeymoon Bay referred to in the story. (Facebook photo)
Old-growth logging protesters block RCMP access on road near Honeymoon Bay

Police were on their way to enforcement in Fairy Creek area when they were stopped

DAVID VAN DEVENTER
Cowichan Citizen and Lake Cowichan Gazette announce new publisher

David van Deventer has been with Black Press Media since 2014

Island Health is bringing a vaccination clinic to Lake Cowichan starting June 23. (Submitted)
COVID vaccine clinic coming to Lake Cowichan as area numbers lag

Clinic will operate at arena starting June 23

The Tsow-Tun Le Lum Society, which has been operating a treatment centre on land leased from the Nanoose First Nation for 35 years (pictured), has begun a fundraising campaign to open a new centre near Duncan. (Tsow-Tun Le Lum Society photo)
New Indigenous treatment centre to be built near Duncan

Centre will help survivors of residential schools

Rick Ruppenthal of Saltair will host a 12-hour talk-a-thon Friday, June 18 over Facebook live. (Photo submitted)
Talk-a-thon to focus on men’s mental health issues

Saltair man spearheading a campaign to generate more conversation during fundraiser

Maxwell Johnson is seen in Bella Bella, B.C., in an undated photo. The Indigenous man from British Columbia has filed complaints with the B.C. Human Rights Tribunal and the Canadian Human Rights Commission after he and his granddaughter were handcuffed when they tried to open a bank account. THE CANADIAN PRESS/HO-Heiltsuk Nation, Damien Gillis, *MANDATORY CREDIT*
VIDEO: Chiefs join human rights case of Indigenous man handcuffed by police in B.C. bank

Maxwell Johnson said he wants change, not just words, from Vancouver police

Two ambulances and a medevac helicopter are on scene at Taylor River Flats rest area on Highway 4 due to a serious motor vehicle incident. (PHOTO COURTESY MAGGIE BROWN)
Highway 4 reopens between Port Alberni and Tofino

Multi-vehicle accident temporarily closed highway in both directions

Tk’emlups te Secwepemc Chief Rosanne Casimir stands outside the former Kamloops Indian Residential School after speaking to reporters, in Kamloops, B.C., on Friday, June 4, 2021.THE CANADIAN PRESS/Darryl Dyck
Kamloops chief says more unmarked graves will be found across Canada

Chief Rosanne Casimir told a virtual news conference the nation expects to release a report at the end of June

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

A woman wears a vaccinated sticker after receiving a COVID-19 vaccine at a vaccination clinic run by Vancouver Coastal Health, in Richmond, B.C., Saturday, April 10, 2021. THE CANADIAN PRESS/Jonathan Hayward
B.C. ranks among highest in world in COVID-19 first-dose shots: health officials

More than 76% of eligible people have received their 1st shot

A screenshot of the First Peoples Cultural Councils First Peoples’ Map. (First Peoples Cultural Council)
Online resource blends B.C.-Alberta’s Indigenous languages, art and culture

Advisor says initiative supports the urgent need to preserve Indigenous languages

An artists conception of the new terminal building at the Pitt Meadows Regional Airport.
Air travel taking off in B.C., but lack of traffic controllers a sky-high concern

There will be demand for more air traffic controllers: Miller

Canadian Armed Forces experts are on their way to North Vancouver after a local homeowner expressed worry about a military artifact he recently purchased. (Twitter DNV Fire and Rescue)
Military called in to deal with antique ‘shell’ at North Vancouver home

‘The person somehow purchased a bombshell innocently believing it was an out-of-commission military artifact’

Amy Kobelt and Tony Cruz have set their wedding date for February, hoping that more COVID-19 restrictions will have lifted. (The Macleans)
B.C. couples ‘gambling’ on whether COVID rules will let them dance at their wedding

Amy Kobelt and Tony Cruz pushed back their wedding in hopes of being able to celebrate it without the constraints of COVID-19

Most Read