If you're an adult, and a relatively healthy one at that, then you've probably been confused in recent years about whether or not you're getting enough vitamin D. Indeed, a series of reports from some of the top medical institutions – including the Institute of Medicine and the Centers for Disease Control and Prevention – have said most adults aren't deficient, even as other top researchers have said most are.
Where there seems to be a little less controversy is vitamin D for kids, who need it to build strong bones and a strong immune system. The IOM in 2010 said children and most adults need 600 international units of vitamin D a day. The American Academy of Pediatrics has a slightly different take: It suggests kids get a lower dose — 400 IU per day — and that they take a daily vitamin to make sure they're getting it.
Now new evidence from two studies finds that not only is vitamin D deficiency common among critically ill kids, but it's also associated with the severity of their illness.
In one study published today in Pediatrics, researchers at Harvard University tested the vitamin D levels of 511 children, up to 17-years-old, who were admitted to six different pediatric intensive care units between November 2009 and November 2010.
They found that 40 percent of the sick kids they tested had less than 20 nanograms of vitamin D per milliliter of blood — meaning they were deficient. This led the researchers to conclude that kids deficient in vitamin D were more likely to be sick than kids with sufficient levels of the vitamin. The kids deficient in vitamin D were also more likely to be in the hospital longer than the other kids.
Another study from researchers in Ottawa, Canada, of sick kids at six Canadian PICUs from 2005 to 2008 came to a similar conclusion.
While both groups of researchers were hesitant to blame vitamin D deficiency for making the kids sick, they called for more studies on whether giving sick kids big doses of the vitamin in the early stages of their illness might be beneficial.
In addition to supplements, vitamin D is readily available in foods like eggs and oily fish and fortified foods such as milk, cereal, orange juice, yogurt and margarine.