In the past, several studies have shown that asthmatics with lower levels of vitamin D had more asthma related problems, including weaker lungs and more frequent asthma exacerbations. It wasn’t clear whether or not these asthma problems were caused by the lack of vitamin D, but there was a great way to find out-- give those with asthma more vitamin D and see what happens.

And that’s just what this recent study by Washington University’s School of Medicine did. The study looked at 400 asthmatic adults with low vitamin D levels. Half were given daily vitamin D supplements. The other half were given a placebo. Both also took corticosteroids to keep their asthma under control.

Unfortunately, the results were not what the scientists hoped for. There was very little difference between those who took the vitamin D and those who took the placebo. In both groups, roughly the same percentage of people continued having asthma related problems. The only major difference was those who took vitamin D didn’t need quite as much of the corticosteroids to control their asthma as those who took the placebo.

But this hasn’t stopped one of the scientists, Dr. Mario Castro, from continuing to treat his patients with vitamin D. “I think there may be some benefit, and vitamin D is inexpensive and has [minimal] side effects” he said. For now, there is still more research being done on vitamin D.