Doctors and other healthcare providers practicing in the Hamilton, Ontario, metropolitan area have a new prescription option to improve patients’ health outcomes: nature. The Hamilton Conservation Authority (HCA), which manages roughly 10,000 acres of forests, wetlands, and conservation areas, as well as a 159-km trail network, has partnered with PaRx (Park Prescription), an evidence-based nature prescription program.

“The prescription, which patients can fill the same way as they would at the pharmacy, is for spending at least 20 minutes in nature per session for a recommended 2 hours per week minimum,” Jennie McCaffrey, vice president of health and education at the BC Parks Foundation in Vancouver, told Medscape News Canada. “What’s exciting is that it’s a one-time lifetime prescription; every single one represents a conversation between a healthcare provider and a patient that’s redefining what healthcare looks like.” The BC Parks Foundation launched PaRx in 2018.

The Fourth Pillar of Health

PaRx grew out of a desire to focus on health as a strategy for building a community of support for nature and protected areas across Canada, McCaffrey explained.

A solid, growing evidence base backs the benefits of spending time in nature. Over the past several decades, research has shown that nature-based (or ‘green’) prescriptions (which include activities like wilderness hikes, biking, time on the water, wilderness-based creative endeavors, or leisure-based outdoor activities like gardening) can improve psychological, physical, and cognitive outcomes. They’ve also been linked to increasing human-nature connections that promote appreciation of the environment. Study findings have underscored that 2 hours or more of direct exposure to nature consistently promotes higher levels of health and well-being than no exposure.

Jake Zamora, MD, an endocrinologist practicing in Barrie, said that he first discovered PaRx when searching online for evidence supporting nature and health outcomes. “We do a lot of chronic disease management (diabetes, thyroid, pituitary and adrenal issues, and reproductive issues). Much of our practice is preventive medicine, and that is where I became interested in incorporating nature, healthy behaviors, and activity into my practice,” he said.

“We talk about nature as the fourth pillar of health, alongside nutrition, exercise, and sleep. Health benefits specifically include reducing stress, lowering blood sugar, strengthening the immune system, and impacting chronic pain and symptoms,” said McCaffrey.

“We’re certainly seeing some long-term outcomes on things like disease prevention and prevention of vascular risks. There’s also some interesting data on kids, such as improved sleep and academic performance,” Zamora said.

Prescribers Wanted

In 2025, Canadian and Australian researchers published the results of a study aimed at assessing Canadians’ awareness of and interest in nature prescriptions. The researchers also examined perceived barriers to these prescriptions and factors that would influence uptake. Among 3593 respondents, more than 75% indicated that they would be likelier to visit natural areas if they were recommended by a healthcare professional.

“The prescriptions give a sense of formality [and indicate] that it’s important enough for me to spend time on it, write it down, and make it an actionable and realistic goal patients can follow through on,” said Zamora. Nature prescriptions are another tool in doctors’ tool belts, he added.

“It’s not something I discuss with every patient. It comes into play when we’re hitting a block or struggling to hit a specific goal, or a patient shares some of their struggles,” he said. “It opens a conversation.”

PaRx has enrolled more than 20,000 healthcare providers (ie, doctors, nurses, and pharmacists) across Canada. Collectively, they’ve written an estimated 2 million nature prescriptions. In Ontario alone, almost 6000 prescribers have signed up for the program.

The HCA pass provides free access for residents of Hamilton (and any patient with a nature prescription) who wish to visit areas such as Christie Lake, Crooks Hollow, and Dundas Valley. But PaRx is not limited to these areas. Patients can also take the prescription to locations such as the Toronto Zoo or the Canadian Museum of Nature, both of which offer a discount on admission, said McCaffrey. A challenge that patients in Ontario might encounter, however, is that only a handful of locations have partnered with PaRx.

“A more meaningful conversation would be to encourage patients to try to incorporate interactions with nature on a daily basis,” said Zamora.

PaRx offers a host of resources and toolkits for doctors and other health professionals who are interested in becoming nature prescribers through its programs. Given the strain on resources and time, prescribers can also link patients to the program’s Connectors: volunteers from professional organizations, forest therapy guides, athletic therapists, and others who help patients follow their nature prescriptions and provide ideas for taking advantage of natural experiences around them.

“Hopefully, we’ll start to see this being introduced to younger generation,” said Zamora. “I appreciate the pressures that all healthcare providers face; you have a small amount of time to deal with a lot of issues. But this can be a quick conversation and something to build on,” he said.

McCaffrey and Zamora reported having no relevant financial relationships.

Liz Scherer is an independent health and medical journalist who frequently reports on global and Canadian health issues.