As you no doubt know, exposure to sunlight causes vitamin D to be produced in your skin. But only a portion of the solar spectrum, known as ultraviolet B (UVB), that has this effect. Other parts of the solar spectrum can have very different and even harmful effects .
Malignant melanoma has been increasing at an exponential rate in indoor workers since before 1940. The reason may be indoor exposure to UVA radiation. Unlike UVB, which is blocked by glass, UVA can pass through windows.
UVA can cause cancerous mutations, and can also break down the vitamin D formed in your skin after outdoor UVB exposure. And vitamin D is a potent defense against melanoma -- melanoma cells convert it to calcitriol, which causes growth inhibition and apoptotic cell death in vitro and in vivo. New research shows that increased UVA exposures and inadequately maintained cutaneous levels of vitamin D promote melanoma.
|Vitamin D Dose Recommendations
||35 units per pound per day
|Age 5 - 10
There is no way to know if the above recommendations are correct. The ONLY way to know is to test your blood. You might need 4-5 times the amount recommended above. Ideally your blood level of 25 OH D should be 60ng/ml.