New research shows that to stay healthy and sane we need full -spectrum sun rather than popping pills. The ultra violet part of the sun is what is missing when we pop Vitamin D. pills and we evolved to absorb healthy, moderate amounts of full -spectrum sunlight and not only for it's Vitamin D producing powers.
Our fear of skin cancer is blinding us to our need for sunlight.
Lack of sunlight interferes with the hormone leptin, which tells us when our stomach is full.
There's also the benefit of being outdoors, which usually means some activity eg walking or cycling, and the psychological benefits of seeing familiar faces, changing seasons etc.