Vitamin D Supplements Do Not Reduce Colds in Asthma Patients

A new study published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine suggests that vitamin D supplements do not reduce the number or severity of colds in asthma patients.

Loren C. Denlinger, MD, PhD, associate professor of medicine at the University of Wisconsin, and colleagues conducted a randomized, controlled trial of adults with mild-to-moderate asthma. Among African Americans in the study, those receiving supplemental vitamin D, rather than a placebo, experienced more colds.

Vitamin D Supplementation Improves Vascular Function
Patients in early stage of chronic kidney disease receiving Vitamin D supplementation demonstrated significant improvement in their vascular functions.

‘University of Wisconsin researchers found that asthma patients with low vitamin D levels are more likely to experience upper respiratory infections asymptomatically than those with normal levels of vitamin D.’

Tweet it Now

The findings surprised the researchers who had previously published research showing a 40 percent reduction in asthma exacerbations in patients with a vitamin D deficiency who achieved normal levels of the vitamin with supplements. Because colds often trigger exacerbations, they hypothesized that vitamin D supplementation would reduce colds and cold severity.

"Other studies of vitamin D and colds have produced mixed results," Dr. Denlinger said. "Most of those studies were conducted among healthy patients. We wanted to ask the same question of a patient population in which the impact of a cold carries greater risk."

The researchers followed asthma patients who were undergoing inhaled corticosteroid (ICS) tapering, Denlinger added, to test the hypothesis that vitamin D might bolster the potency of the ICS.

Vitamin D Pill Helps Lower Risk of Heart Disease
Taking vitamin D supplements can improve fitness levels and lower cardiovascular risk factors such as blood pressure, finds study.

The multi-center AsthmaNet Vitamin D Add-on Therapy Enhances Corticosteroid Responsiveness (VIDA) trial enrolled 408 adults with mild-to-moderate asthma whose vitamin D levels were insufficient or deficient (25-OH-D3 < 30 ng/mL). Those enrolled had asthma symptoms despite low-dose ICS therapy. The patients were randomized to receive either vitamin D supplementation (100,000 IU once, then 4000 IU daily) or placebo for 28 weeks. Neither the patients nor their physicians knew whether they received vitamin D or the placebo.

During that time, about half the participants experienced at least one cold. The severity of their colds was measured by the Wisconsin Upper Respiratory Symptom Survey-21 (WURSS-21).

Don�t Burn a Hole in Your Pocket! Vitamin D and Calcium Do Not Prevent Colon Cancer
Daily supplementation with vitamin D3, calcium or both after removal of colorectal adenomas did not significantly reduce the risk of its recurrence.

The researchers analyzed separately the results of the 82 percent of participants receiving supplements who achieved vitamin D sufficiency within 12 weeks. Achieving sufficiency made no difference in number of colds or their severity this group experienced.

The researchers wrote that one possible explanation for the unexpected finding: asthma patients with low vitamin D levels may be more likely to experience upper respiratory infections asymptomatically than those with normal levels of vitamin D, which is known to trigger an inflammatory response. This inflammatory response may, in turn, reduce the risk of lower airway infections, which are triggers for asthma exacerbations.

Vitamin D Insufficiency may Fast-Track Cognitive Decline In Older Individuals
Vitamin D insufficiency iss associated with significantly faster declines in both episodic memory and executive function performance, like dementia.

Although there are other reasons to recommend vitamin D supplements for asthma patients, including the fact that they are at greater risk for bone weakening, Denlinger said, "we can't recommend vitamin D for the prevention of colds."

Source-Eurekalert