Light!

Getting out in the sunlight is good for your health and it is good for your mental health as well.  People tend to get depressed when the natural sunlight is low during the winter, and this is often called seasonal affective disorder.  It can be helped by getting out in the sun or with artificial lights that synthesize sunlight.

Check out these resources:

Mayo Clinic 

Columbia

Benefits of Sunlight 

Did you realize that people do something akin to photosynthesis when exposed to sunlight?  We synthesize vitamin D through a chemical reaction in the skin.  I think that's completely fascinating!  

Sunlight has many, many benefits.  Go outside.  

You Shouldn't Shun the Sun.  

Get out there.  Plant some flower bulbs or do some guerrilla gardening with seed bombs, take a walk with a loved one or just sit down on a bench or your front porch for a little while.