No matter what our mothers say, you can't catch a cold by going out in the rain without your umbrella. And now it seems you can't stop a cold with Vitamin D. But did the stories make that clear enough?
Michelle Roberts at BBC News online starts off well, reporting that a New Zealand study in the Journal of the American Medical Association had found "no convincing evidence to show that taking vitamin D supplements will fend off a cold." The researchers, she wrote, "did the 'gold-standard' of tests–a randomized placebo-controlled trial."
But after three short grafs, she segues to a "leading UK cold expert" who says Vitamin D can "give the immunity a much-needed boost during the winter." Wait a minute–isn't that what the JAMA study just disproved? This guy gets seven grafs in a row to knock down the study Roberts just reported. She also lets him throw in a good word for echinacea, just for the heck of it. So much for the gold-standard of tests–apparently it wasn't gold enough for Roberts.
At the Booster Shots blog of The Los Angeles Times, Jon Bardin lays out the basics, noting that Vitamin D's value in preventing colds has been debated, but that the previous studies "were poorly controlled adn the results have been mixed," according to the authors of the new study. And instead of immediately turning to a contrary view, he quotes an accompanying editorial in JAMA that says the New Zealand study "is well-conducted and its results should be trusted." That shouldn't be the last word, but quoting the editorial is usually a better bet than looking for a reflexive disagreement.
Genevra Pittman of Reuters noted that the study addressed the value of Vitamin D in healthy adults, but that children–or adults deficient in the vitamin–might benefit. Rita Rubin, at WebMD, neatly explains the rationale for investigating Vitamin D, but she makes clear that the new study is persuasive, and she includes the footnote about children or Vitamin D-deficient adults.
Richard Knox of NPR also explains why Vitamin D seemed like a good way to prevent colds, noting that the prestigious Institute of Medicine report had recommended more research on the subject almost two years ago. He uses the IOM report to provide more background and context for the study, which is helpful. And Knox mentions echinacea, zinc, Vitamin C, and a catalogue of other "nostrums" that are considered by the Cochrane Collaboration to be "ineffective, questionable, or possibly harmful."
Overall, the press performed well with this one.
-Paul Raeburn
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