Sources

Children & Adolescents	Calcium (Daily)	Vitamin D (Daily)
1-3 years	700mg	600 IU
4-8 years	1,000mg	600 IU
9-18 years	1,300mg	600 IU
Adult Women & Men	Calcium (Daily)	Vitamin D (Daily)
19-50 years	1,000mg	600 IU
Men 51-70 years	1,000mg	600 IU
Women 51-70 years	1,200mg	600 IU
Adults 71 years and older	1,200mg	800 IU

You need to eat fat to absorb vitamin D. Its naturally found in fish oil and fatty fish. It can also be found in dairy products like cheese, milk as well as well as egg yolks. People can also get vitamin D when they are exposed to the sun.
Vitamin D can increase the levels of cholesterol in the blood. This can be used to regulate the levels but also causes problems when there is too much.
There are vitamin D supplements that are used for people who are vitamin D deficient. There are two different types,D2 and D3 but they are both equally effective. The only difference between the two is in their side chain structures.