“A lot of clinicians are acting like there is a pandemic” of vitamin D deficiency, said Dr. JoAnn E. Manson, a preventive medicine researcher at Brigham<br />and Women’s Hospital in Boston who helped write an Institute of Medicine report on vitamin D.<br />“That gives them justification to screen everyone and get everyone well above what the Institute of Medicine recommends.”<br />In fact, the institute committee on which Dr. Manson served concluded in 2010<br />that very few people were vitamin D deficient and noted that randomized trials had found no particular benefit for healthy people to have blood levels above 20 nanograms per milliliter.<br />“A lot of people thought that if they were fatigued or sad or they did not feel well, they might be vitamin D deficient.”<br />In 2007, Dr. Holick published a paper in The New England Journal of Medicine asserting<br />that vitamin D levels now considered normal — 21 to 29 nanograms per milliliter of blood — were linked to an increased risk of cancer, autoimmune disease, diabetes, schizophrenia, depression, poor lung capacity and wheezing.<br />Still, vitamin D has become “a religion,” said Dr. Clifford J. Rosen, an osteoporosis researcher at the Maine Medical Center Research Institute<br />and a member of the Institute of Medicine’s committee.<br />Because many people have little exposure to sunlight, especially those living in northern climates in winter, some investigators became concerned more than a decade ago<br />that large swaths of the population were not getting enough vitamin D.<br />One is Dr. Michael F. Holick, a professor of medicine, physiology and biophysics at Boston University School of Medicine and a leading proponent of the idea<br />that just about everyone needs a vitamin D supplement.
