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Asthma Health Center

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Vitamin D May Improve Asthma Control

Study Links Vitamin D Deficiency and Asthma Severity

More Research Warranted continued...

Michael Holick, MD, PhD, a professor of medicine, physiology, and biophysics at the Boston University School of Medicine and the director of the Vitamin D, Skin, and Bone Research Laboratory there, thinks the jury is in regarding the role that vitamin D supplementation can and should play in treating and preventing asthma.

"This article provides strong evidence that vitamin D is altering the immune system and preventing asthma at a biochemical level," he says.

"Winter is coming on and flu season is coming on, and that is all the more reason for parents to increase vitamin D in their children," he says. "Recent studies suggest that it will reduce risk of wheezing disorders, including asthma," he says.

The Institute of Medicine is considering whether to raise its guidelines for vitamin D intake. The current guidelines call for 200 IU/day.

Low Vitamin D Linked to Worse Asthma, More Steroids

"Vitamin D ... has effects on many immune cells and we are learning more and more about the impact that it can have on allergic diseases such as asthma," says Pia Hauk, MD, an assistant professor of Pediatrics at National Jewish Health in Denver.

"If you have low vitamin D levels, your asthma may be worse and you may have to take more medication to control it," she says. But "new research suggests that if we normalize vitamin D levels, you may need less medication to get control of the inflammation."

This is important to many parents, she says.

"Many parents are very concerned about side effects of inhaled steroids and would be very happy to get away with less medication," she says.

Hauk routinely tests vitamin D levels in her patients. "If it is low, I will put them on a supplement and check the levels again after three months," she tells WebMD. "The next step is to conduct a study where people with asthma who have low levels of vitamin D are treated with supplements, and then study their lung function, steroid use, and asthma exacerbations once their vitamin D levels are normal," she says.

These studies will provide definitive answers on the role that this vitamin has in asthma treatment, she says.

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