Vitamin d rich foods and supplements
RDA is about 400 IU
[The IU to microgram conversion is vitamin specific. For vit D (cholecalciferol) is 1IU = 0.025 micrograms.) Big bottle = 2,200 IU i.e. 55 micrograms. Small bottle = 10 micrograms i.e. 400 IU.)
Foods:
cod liver oil: 500 IU per teaspoon.
oily fish: mackerel (65% of IU per 3 oz cooked); sardine (27%); salmon (97%);
portabello mushrooms (375 IU per mushroom)
eggs (7% per egg)
koko (150% of D2 per carton)
It's also in dairy and some fortified foods
Vitamin D is an essential vitamin required by the body for the proper absorption of calcium, bone development, control of cell growth, neuromuscular functioning, proper immune functioning, and alleviation of inflammation.
A deficiency in vitamin D can lead to rickets, a disease in which bones fail to properly develop. Further, inadequate levels of vitamin D can lead to a weakened immune system, increased cancer risk, poor hair growth, and osteomalacia, a condition of weakened muscles and bones.
SUPPLEMENTS
The recommended form of vitamin D is vitamin D3 or cholecalciferol. This is the natural form of vitamin D that your body makes from sunlight. Supplements are made from the fat of lambs' wool.
Many supplements contain vitamin D as vitamin D2 or calciferol (or ergocalciferol), which is derived from irradiated fungus and is not the form of vitamin D naturally made by your body.
Sunlight is probably even better than vit D3 supplements.