There’s been a lot of expectation that the Recommended Daily Allowance for Vitamin D would officially be increased; the level for adults is 400IU. Vitamin D is seen as a measure of “wellness” by some doctors now and as many as 9 out of 10 patients have been found to be deficient in this important supplement. One doctor quit testing his patients because over 90% of the ones he had tested were deficient.
A "high" daily dose of Vitamin D may help prevent bone fractures in older adults; "high" being over the 400IU recommended. Preliminary research shows intakes of between 1000-2000IU as being safe and effective for adults. One doctor I read about is taking 3000IU a day. Personally, I have have upped my intake to 1000IU daily.
Vitamin D mainly comes from sun exposure, and from a few foods such as egg yolks, fish, and fortified milk and grains. It is an important component in helping your body absorb calcium for strong bones and healthy teeth. Recent research, however, is showing that Vitamin D is important for far more than just your bones: it may protect against heart disease, some cancers, severe asthma in children, and reduced mental function. It may also help with fibromyalgia, diabetes, multiple sclerosis, high blood pressure, general muscular aches and pains, and in supporting your immune system.
The Institute of Medicine recently released their report on “Dietary Reference Intakes for Calcium and Vitamin D.” While the RDA has been changed, it has only been increased to 600IU for children and adults, 800IU for those over the age of 71. The safe upper limit was changed from 2000IU to 4000IU. Calcium RDA levels remain the same. You can see the full report at http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Report-Brief.aspx.
I found this to be a bit disappointing. From what I have read, the expected new RDA was 1000IU. With so many people deficient in this very important vitamin, I feel more emphasis needs to be placed on sufficient levels. There are concerns that this issue will get worse before it gets better: obesity causes Vitamin D to disappear from the bloodstream and it is a lot harder to get levels back to normal after this occurs. Vitamin D levels have also been found to be low in African-Americans and Hispanics (due to their darker skin blocking sunlight).