What is vitamin d needed for in the body?

Vitamin D regulates the blood levels of Calcium and Phosphorus.It increases the absorption of these minerals from intestine and their deposition in bones.

Sources:

1- Fish liver oil

2- Milk

3- Ghee

4- Butter

Diseases:

1- Rickets in children

2- Osteomalacia in adults

Bone Mass Density - (the amount of calcium deposited in the bones) peaks at 30 and after this stage in life no further calcium can be deposited, it is therefore essential for children to get Vit D which aids Calcium absorption - to ensure a high BMD by age 30.