Twenty-first century life -- long working hours and commutes, screen addiction, lack of accessible urban green spaces -- has broken Americans' relationship with nature. That ups the risk for everything from obesity to nearsightedness, not to mention heart disease, diabetes and cancer. But getting out and about could help reverse that, and boost your mental health, cognition and immune function, too. A study in Scientific Reports suggests that you should spend at least 120 minutes a week in nature. Try getting out whenever you can, anywhere there's greenery -- a park, your yard, the field out back. Early morning, star-spangled nights, lunchtime, do yoga in your friend's backyard or meditate under a tree. Heck, put some basil in a window box and run your hand over the leaves to get lost in the aroma. Every contact with nature improves your life.