Reveling in Dimness

Window light illuminated this gymnasium during an afternoon.

   Do we crave exposure to natural light? 
   When the weather is inclement, I visit a public gymnasium. My arrival triggers a motion detector. Fluorescent lights activate. For exercise, I walk round and round a basketball court.
   Last week the fluorescents didn't turn on right away. I relied on window light.
   I preferred the window light. It created a more relaxing ambiance. I reveled in dimness.
   By design, do our bodies prefer natural light?
   Natural light dances across floors and walls. It brightens and dims. It responds to the rotation of the earth. Our circadian rhythms are tuned into this light show.

Fluorescent lights came on later.

   Artificial lights--fluorescent, LCD's, and others, don't shift around. Nor do they vary in output.  They're consistency disrupts our circadian rhythms.
   Taking a walk. Driving a car. Sitting near a window. Might several minutes per day of exposure to natural light, without competition from other lighting, improve our well being?
   Call it an optical vitamin.