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Ultraviolet and
Vitamin D
Ultraviolet (UV) radiation from the sun is necessary to produce
Vitamin D in the body, depending on exposure to UVB rays. The
time to synthesize vitamin D depends on the angle of the sun,
latitude, skin tone, season and amount of skin exposure.
In wintertime, many parts of the world don’t have enough
sunshine for adequate amounts of vitamin D synthesis. At
the same time, in the summertime, people should limit their
exposure to UV rays to safely get Vitamin D, since too much
exposure causes sunburn and is a major risk factor for skin
cancer.
The sun’s UVB rays cannot penetrate through windows.
So people who work next to sunny windows are still prone to
vitamin D deficiency.
4 5 °
THE “SHADOW RULE”
The Shadow Rule: If your shadow is longer than you are tall, you will not make vitamin D.
L I G H T & W E L L - B E I N G
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