Spending time in forests, hiking in mountains, and just being outside can lead to significant health benefits.

Studies have shown that walking in the woods can improve blood pressure, boost mental health, and decrease cancer risk.

So go spend some time "forest-bathing" to improve your health.

Many people spend workdays indoors under fluorescent lights and in front of computers, then return home to bask in the glow of television screens.

But research suggests it's important to make time to get outdoors as well, since doing so is beneficial — maybe essential — for human health. Psychologists and health researchers are finding more and more science-backed reasons we should go outside and enjoy the natural world.

In her book, "The Nature Fix: Why Nature Makes Us Happier, Healthier, and More Creative," journalist Florence Williams writes that she started investigating the health benefits of nature after moving from the mountainous terrain of Boulder, Colorado, to what she describes as "the anti-Arcadia that is the nation's capital": Washington, DC.

"I felt disoriented, overwhelmed, depressed," she wrote. "My mind had trouble focusing. I couldn't finish thoughts. I couldn't make decisions and I wasn't keen to get out of bed."

We don't all need to move to beautiful places like Boulder — there are good reasons for many of us to live in bigger cities.

But humans do need to spend time in natural environments if they want to improve their physical and mental health. That could mean taking advantage of hiking trails near your home, playing in the snow, swimming in the ocean, or just spending time every week in a local park.

Here are 12 reasons why it's so important.