An analysis of data from 145 people who gardened and 146 who did not revealed that the gardeners increased their intake of fiber, spent more time engaged in moderate or vigorous physical activity and experienced reductions in stress and anxiety, according to the report published in Lancet Planet Health. It's the first randomized, controlled trial of community gardening.
The goal of the study was to see if gardening can spur people to adopt healthier habits, the study’s lead author, Jill Litt, Ph.D., professor at University of Colorado, Boulder and senior researcher at the Barcelona Institute for Global Health, tells TODAY.com.
Almost 70% of Americans are overweight or obese, Litt says.
“These are big numbers that call for big solutions," she adds. "We know that education doesn’t work. Telling people to lose weight doesn’t work, and putting people on restrictive diets doesn’t work.”
Litt and her team suspected that one way to help people live healthier lives could be to get them engaged in an enjoyable activity that lends to better food choices and more exercise. Community gardens seemed like an ideal strategy as planting and maintaining the crops would provide physical exercise and the resulting fresh produce would improve diet.
To test the theory, researchers recruited 291 people on the wait list to use a plot of land in one of 37 Denver-area community gardens. Half of the participants moved to the top of the wait list and got their plots, and half did not. The participants who got a garden plot were provided with seeds, seedlings and an introductory course in gardening. (Those who didn’t, aka the control group, got a garden plot the following year as a thank you for participating.)
Participants’ health was assessed at three points during the study via surveys that included questions about stress and anxiety, as well as height, weight and waist circumference. They were all also asked to wear a thigh-mounted accelerometer for a week after each assessment so the researchers could keep track of how much the participants were moving.
Community gardening reduces cancer risk and boosts mental health
When Litt and her team analyzed their data, they found "concrete evidence that community gardening could play an important role in preventing cancer, chronic diseases and mental health disorders," Litt said in a press release.
Compared to those in the control group, the gardeners on average took in up to 1.4 more grams of fiber each day, exerted themselves at a moderate or vigorous level for an extra 5.8 minutes a day, and showed a reduction in anxiety and stress.
“From a clinical perspective, anything that gets stress and anxiety levels down is really good news,” Litt explains. “Once (anxiety and stress) start the cycle of inflammation, it puts you on a trajectory for chronic disease." (Research suggests anxiety disorders can increase inflammation throughout the body.)
While the increase in physical activity may seem small, it adds up, Litt says, coming out to about 40 minutes a week. And while that doesn’t by itself hit the recommended 150 minutes a week, it got participants almost one-third of the way there.
Participants in the gardening group did consume more fruits and veggies, but the difference wasn’t statistically significant when the researchers first looked at the data. However, when Litt and her team realized participants weren't growing much fruit, they reanalyzed the data to focus on veggies. They found the gardeners did consume more vegetables to a statistically significant degree.
The takeaway from this study, "which is something I tell my patients, is that physical activity of any sort is beneficial," Dr. Sean P. Heffron, assistant professor at the Center for the Prevention of Cardiovascular Disease at NYU Langone Health, tells TODAY.com. “It doesn’t need to come from what we think of as exercise — going to the gym or running around the park. It can just be something you enjoy doing.”
Moreover, community gardens can be a way for people who live in food deserts (areas that lack places to buy affordable, healthy foods) to get fresh vegetables and fruit, Heffron says: “If you’re growing things, you’ve already chosen things you like to eat, and now you’ve got ready access."
And it’s not surprising that being outside and gardening reduced people’s stress levels, Heffron explains. There’s research showing that just being out in nature can make you less stressed.
The study shows that “low-tech things can make a significant impact on people’s health,” Dr. Daniel Sullivan, internal medicine physician at the Cleveland Clinic, tells TODAY.com. “Kudos to the people who did this brilliant study,” Sullivan continues, adding that the study “is incentivizing my wife and me to get a rooftop garden plot.”
The new research is “important,” Julia Denison, a registered dietitian at the University of Pittsburgh Medical Center, tells TODAY.com. “Community gardens are a super cool concept that I hope will continue to be popular throughout the country. Gardening is a good hobby that can relieve stress and anxiety.”
Another benefit: These kinds of gardens also offer the opportunity to build a sense of community, Denison says.