Vitamin D (Choleacalciferol)

USE: In the past, Vit D was thought to be mainly responsible for bone health, as it allows the body to absorb calcium and build bones. Research in this field has been growing rapidly over the years and the consensus is that Vit D is important for just about every organ in our bodies. Nutrition experts like Harvard's Walter Willet say adequate vitamin D may help prevent disease. A daily dose of vitamin D could cut the risk of cancers of the breast, colon and ovary by up to a half, a 40-year review of research has found. 
SOURCE: Dietary sources come from Milk/Dairy, fish, liver and eggs. However the best source of Vitamin D is from the sun. The recommendation is that you expose yourself to the sun for 15mns mid-morning or mid-afternoon when the sun is still high and emitting the most UVB's (avoid midday sun), with face and arms exposed without sunblock. Do not put sunblock on your children before they goout to play. Let them run around outdoors and at the beach for about 20mns before you apply sunblock, assuming there is a need for it. Its all about creating the right balance between allowing your body to recieve what it needs from the sun and protecting it from the potential harmful effects.