RE: The Importance of Vitamin D: From Sunlight to Bone Health

When you decide to take that morning walk down your street and the sun shines on your skin, the sun shines UV-B on the skin where it turns 7-Dehydroxycholesterol into vitamin D3 (cholecalciferol).

It seems to me that this conversion depends on the amount of UVB that one receives. Apparently, the sun filters out UVB radiation. Windows and sunscreen also filter the rays.

It appears that the intensity of UVB radiation changes by location and time of the year.

Intense UVB radition causes skin cancer.

It seems to me that the trick is to figure out the best time to go outdoors.

The earth is tilted. So sun rays travel through more atmosphere during the Winter. I understand that people in Northern climates receive insufficient UVB rays during the Winter. This is the most likely reason that people in Northern climates lost their natural skin pigmentation.

I live in Utah. In the Winter I try to catch some sun at noon. In the summer I avoid being outside at noon and opt for mornings and evenings.

I wish that there was better guidance on this issue. The AMA is so worried about skincancer that they fail to feed us good information.

!WINE