U.S. national parks have long been called “America’s best idea.” President Trump appears to disagree. His attacks on them threaten our health. The administration has fired about 1,000 National Park Service (NPS) employees (or 9% of NPS workers). Over 34 NPS leases, including visitor centers and museums, are set to be terminated. Budget cuts and privatization are also back on the table.

This could be detrimental. Research shows that nature is one of the best things for your health and well-being (the World Health Organization even calls it the greatest source). Spending time in green spaces can reduce stress, lower blood pressure and decrease the risk of anxiety and depression. Australian researchers estimate that protected areas contribute $6 trillion annually to global mental health by improving well-being and reducing health care costs.

Green exercise, or physical activity in nature, has better health benefits than exercising indoors too. Just a 30-minute visit to a park can improve heart health, circulation, and boost immune function. Even the natural sounds of birds singing and water flowing can improve relaxation and focus.

Parks can also improve health and longevity by promoting social connections through organized activities and casual meet-ups. Studies have found that being outdoors boosts creativity, problem-solving and generosity, making people more cooperative and kinder, even to strangers. This is one reason why park-based health programs are supported by health care institutions.

To benefit future generations in these ways and others, the NPS was established in 1916 by President Woodrow Wilson. Since then all presidents except Trump have protected more land than they removed. But staffing shortages and budget cuts can make national parks less safe and harder to visit. With a $22 billion maintenance backlog and fewer rangers, trails, roads and restrooms, these resources are falling apart.

At the Grand Canyon, a broken water pipeline remains unfixed after key workers were fired, while Yosemite visitors have been trapped in restrooms after the park’s only locksmith was let go. Emergency response times are slower, and onsite public safety education is dwindling.

One of the latest changes the Trump administration is pushing toward is privatization. Beginning in his first term, the Trump administration has considered privatizing services, like campgrounds, food services and Wi-Fi, in national parks. This raises big concerns about the impact on visitors’ health and the accessibility of these public spaces. Privatization could drive up prices and make parks inaccessible for low-income families and older adults who rely on senior discounts.

As parks get more commercialized (think expanded Wi-Fi, food trucks and Amazon deliveries), overcrowding could worsen, increasing pollution, accidents and stress. What’s worse, if ranger positions are privatized, it could reduce vital public health education and safety efforts. Park rangers play a vital role in protecting and preserving historical sites and natural resources (e.g., fire prevention and reduction initiatives).

Fossil fuel production is trumping conservation efforts too, with the Trump administration working on rolling back protections for hundreds of public lands and waters to allow more mining, drilling and logging. This puts both people and wildlife at risk. Pollution from emissions can lead to respiratory issues, and chemicals from oil extraction can increase cancer and neurological risks.

Water contamination is another major concern, threatening drinking water quality for millions and the species that rely on these habitats full time. Despite generating $55 billion in 2023 on a $4.7 billion budget, national parks are becoming less accessible, less safe and increasingly at risk. And the way forward is cloudy.

Previously, the National Parks Conservation Association recommended finding other funding sources to tackle the maintenance backlog, such as giving the parks back to local Native communities and tribes to manage. Today, many are simply focused on halting and reversing Trump’s current actions: restore funding and rehire staff, especially before the summer rush of visitors.

Our health is closely tied to the health of the land, water, air and other species. Making sure the access to nature, and nature itself, isn’t disrupted or destroyed is wildly important, not just for public health but also as a smart investment in community well-being, economic resilience and environmental sustainability.