The Institute of Medicine panel that has been deliberating for several years over how much Vitamin D we should take finally issued their guidelines this week and though it was increased to 600 IU daily for Americans and Canadians up to age 70 (up from 200 in 1997), it was much lower than what many doctors and medical groups thought they would and should recommend. There doesn’t seem to be any squabble over the importance of vitamin D to our health. It is essential for bone health and there is ample evidence to suggest that it can help prevent the development of some cancers (breast, prostate, colon); contribute to cardiovascular health; and stimulate immune responses to infectious diseases. The debate is about how much is needed to realize vitamin D’s full benefits.
So why are the new dosing recommendations so conservative if the benefits of vitamin D have proven to be so substantial? The IOM said they based their recommendations on the levels needed to maintain strong bones alone since they did not believe that there was enough evidence to prove that low levels of vitamin D causes diseases. As they wrote in the recommendations: “Past cases such as hormone replacement therapy…remind us that some therapies that seemed to show promise for treating or preventing health problem ultimately did not work out and even caused harm. That is why it is appropriate to approach emerging evidence about an intervention cautiously, but with an open mind.”
Some of the leading Vitamin D researchers expressed their disagreement with the IOM’s recommendations on the website of Grassroots Health, an organization of leading vitamin D scientists that educate healthcare practitioners and consumers about the importance of vitamin D. They have stated that 40-75 percent of the world’s population is vitamin D deficient. Its founder and director, Carole Baggerly, wrote that the IOM panel “set aside many studies that did not fit their narrow definition of evidence.”
Cedric F. Garland, MD, a professor of the University of California San Diego School of Medicine, said that “pending testing, the minimum intake for all men, women and children one year and older should be 2,000 IU/day and the upper limit should be 8,000 IU/day. Moreover, adults should be tested every two years, preferably in March.
Dr. Carlos Camargo, an epidemiologist and Associate Professor of Medicine at Harvard Medical School says that public health problems like vitamin D deficiency shouldn’t be solved with a one-size fits all approach. Rather, people should get their blood level of 25(OH)D tested and tailor the vitamin D dose and frequency for their needs. ”Vitamin D is a hormone and just like any other hormone, good health requries a level that is not too low but also not to high. This optimal level may differ for different people…but my guess is the optimal level for most people is a 25(OH)D level around 40ng/ml.”
So where does that leave us? As with hormone therapy, there is a lot of research that the public can read first-hand. And there is also a simple blood test to determine if you are vitamin D deficient. Based on those results and armed with information, you will be in a better position to discuss your options with your physician and take a vitamin D supplement in a dose that is right for you.
The website of GrassrootsHealth is a good place to start your research. It offers an enormous amount of information and video presentations by leading vitamin D researchers and scientists. You can also order a home test kit on their website or through the Canary Club.