Having seen several major news outlets reporting on a new CDC report stating that only 8% of Americans could be considered “deficient” in vitamin D, and that another 25% were merely “at risk” of deficiency, I find myself praying for patience. The media, unfortunately, appear to have mostly missed the fact that the CDC findings are based upon the highly flawed Institute of Medicine vitamin D recommendations that were issued last December (see my prior blog post for the details). As I noted in that earlier post, concluding that most North Americans have adequate vitamin D levels based upon wholly inadequate standards is circular logic — when you set the bar low, of course more people can get over it! That’s almost like saying that children are literate when they have learned the alphabet. By IOM’s standards, approximately 33% of the population is below adequacy. By the standards accepted among those of us who’ve examined the data — all the data, not just the very limited portion the IOM used to formulate its recommendations — a fairly significant number of those considered “sufficient in vitamin D” would be added to this group.
As I stated before, there is more than ample evidence showing that higher vitamin D levels are associated with improved health. It’s a well-known fact among those who study osteoporosis that improving vitamin D status to a level of 32 ng/mL or higher — considerably above the 20 ng/mL threshold the IOM considers adequate — frequently leads to an improvement in bone health. I can only speculate as to why the IOM researchers chose to ignore the collected data about the benefits of higher vitamin D levels in favor of the lower standards they proposed.
But the other point that most news outlets miss is that even using the IOM’s restrictive standard, at least a third of Americans are below the level of adequacy. That translates to almost 100 million individuals. This is not a negligible number of people! The media is presenting this story as the “good news” that the majority of us have adequate vitamin D — but even if I believed that, which obviously I don’t, I can’t possibly be positive about the fact that hundreds of millions of people are at risk of osteoporosis and other serious health concerns for lack of a simple, inexpensive vitamin easily obtained at a pharmacy.
Like many other researchers, including eminent vitamin D experts Dr. Robert Heaney, Dr. Cedric Garland, and others who joined a recent GrassRootsHealth Call to Action Panel, I believe that individuals and their healthcare providers should regard the IOM recommendations with great skepticism. I support the recommendation that individuals should receive regular testing for vitamin D and strive for a serum vitamin D level in the range of 40–60 ng/mL. And I heartily endorse the call for action to address vitamin D deficiency worldwide.
Looker, A.C., Johnson, C.L., Lacher, D.A., et al. Vitamin D status: United States, 2001–2006. US Department of Health & Human Services, Centers for Disease Control and Prevention, NCHS Data Brief No. 59, March 2011.
Pearson, C. CDC: Only 8 percent of Americans vitamin D deficient. The Huffington Post, March 31 2011.
Roan, S. Vitamin D levels are adequate in most Americans, survey finds. The Los Angeles Times, March 30, 2011.
I’m Dr. Susan Brown. I am a nutritionist, medical anthropologist, writer, and speaker. Get my free weekly newsletter here.