The Institute of Medicine's 14 member panel has released the findings of their two year study of vitamin D and increased the recommended dietary allowance of vitamin D to 600 international units per day from the previous level of 400 international units per day. This is the second increase since the 1997 levels which were 200 international units per day.
The panel was formed at the request of the governments of the United States and Canada. The panel examined thousands of publications and studies in order to determine how much vitamin D and calcium people needed for good health, how much was too much and what is the level for deficiency.
Vitamin d testing has exploded over the last few years and labs have started reporting that levels below 30 nanograms per milliliter is a deficiency. The Institute of Medicine's new study states that a level of 20 to 30 nanograms per milliliter to be the level that is needed for good bone health for practically all individuals, therefore, a deficiency would exist only below 20 ng/mL.
When labs use the below 30 nanograms level as a deficiency then an estimated 80 percent of the population is deemed vitamin d deficient. However, the Institute of Medicine is lowering that bar to 20 nanograms which would mean that we don't actually have a vitamin d epidemic in the United States.
The medical community has released thousands of studies over the last several years supporting an increased need for vitamin d supplementation to levels between 1000 - 2000 IU and citing increased diseases in people with low levels of vitamin d. The media has highly publicized vitamin d as a panacea for the common cold to cancer. So how do we make sense of the new government study?
The government is required to issue one number which is supposed to be for everyone in the United States. Certainly, the government would not recommend one level for the people of Vermont and another for the people of Florida, but that is how vitamin d works based on your distance from the equator. And certainly there would be an uproar if our government made one recommendation for whites and one recommendation for blacks, but again that is how vitamin d works based on the color of your skin and its ability to absorb the sun's rays and convert them to vitamin d.
"the committee emphasizes that, with a few exceptions, all North Americans are receiving enough calcium and vitamin D. Higher levels have not been shown to confer greater benefits, and in fact, they have been linked to other health problems, challenging the concept that “more is better.”"
So the
Institute of Medicine has to walk this very narrow line of making a recommendation that will work for every man, woman and child in this country - as their tagline on their website says "Advising the Nation". So while medical evidence exists that where you live or the color of your skin will effect your vitamin d level, the committee had to ignore these facts in their recommendations and find a cautious level to establish for all.
Even with the recommended lower level of 20 ng/mL many people are still vitamin d deficient. If you want to heed the cautionary levels recommended by the IOM then test your vitamin d level and if it is below 20 ng/mL then take the recommended supplement of 600 IU per day. Test your vitamin d again in three months and see if there has been improvement. Many in the medical community will tell you that you cannot raise your vitamin d level on 600 IUs per day.
The one thousand page report issued by the IOM will be read in full by few and rehashed by many. Personally, I will not read the entire 1,000 report since I had trouble getting all the way through Dr. Holick's 336 page book on vitamin d. However, I do know that I can have my
vitamin d level tested and know that I need to be at minimum in the 20 - 30 ng/mL range. My recent vitamin d level came in at 14.6 ng/mL and I live in the sunny south and am white. Just to get to the cautiously safe level of 30 ng/mL means doubling my vitamin d level which will take additional supplementation and additional sun exposure. The good news is that I can test again and find out if I am making progress.
While the IOM report sounds like a cautionary warning, the truth is we still have the tools available to find out what works for each of us individually and this is not something the government will ever be able to do - determine what is best for you.