Gardeners Have Lower Risk of Chronic and Mental Illness, Study Finds

A first-ever randomised, controlled trial of community gardening has found that beyond eating more fibre and getting more physical activity—two known ways to reduce the risk of cancer and chronic diseases—those who pottered around in gardens also had significantly reduced levels of stress, anxiety, and risk for mental illness.

The new study of low-income households has found that gardeners who came into the study most stressed and anxious saw the greatest reduction in mental health issues.

“These findings provide concrete evidence that community gardening could play an important role in preventing cancer, chronic diseases, and mental health disorders,” senior author and environment professor at the Department of Environmental Studies at the University of Colorado Boulder Jill Litt said.

“No matter where you go, people say there’s just something about gardening that makes them feel better.”

Outdoor air, infused with the molecules of a million plants and biochemical processes, has powerful healing effects we are only beginning to understand. (AshTproductions/Shutterstock)

The study recruited nearly 300 gardening beginners, with an average age of 41.

Half were assigned to the community gardening group and received a free community garden plot, some seeds, an introductory gardening course, and a study partner. The other half were assigned to a control group.

Both groups took regular questionnaires about their diet, mental health, and body measurements.

Two seasons later, the gardening group were eating seven percent more fibre daily than the control group.

“An increase of one gram of fibre can have large, positive effects on health,” co-author and director of the University of South Carolina’s cancer prevention and control program James Hebert said.

Fibre exerts a profound effect on inflammatory and immune responses, influencing everything from how we metabolise food to how healthy our gut microbiome is to how susceptible we are to diabetes and certain cancers, the researchers noted.

Prof. Litt said community gardening is transformational and even life-saving, particularly for low-income immigrants living in apartments.

“Even if you come to the garden looking to grow your food on your own in a quiet place, you start to look at your neighbour’s plot and share techniques and recipes, and over time relationships bloom,” she said.

Gardening Tips

National Seniors Australia recently outlined some guidelines for avoiding getting sick while gardening, in light of increased cases of Legionnaires’ disease—a severe form of pneumonia—from potting mix and soil.

People are advised to wear gloves and masks when working with garden soil or potting mix, particularly if one is older, a smoker, or has a weakened immune system.

Harriet Whiley, associate professor in environmental health at Flinders University, said to open potting mix bags away from the face and avoid shaking the bag before emptying it.

“Legionnaires’ disease is not transmitted from person to person, but through inhalation or aspiration of the Legionella bacteria,” Whiley said.

“This is why it is important to wear a mask, wet down the soil, and wear gloves or wash hands when handling potting mix.”

Wetting the potting mix first helps prevent any contaminated potting mix dust from blowing up into the air and being inhaled.

The gardening study was published on Jan. 4 in the journal Lancet Planetary Health.