Vitamin D: A New Option in the Fight Against Asthma?October 27th, 2014
By Charles Snyder, PharmD Student Cedarville University
Most people are either affected by asthma or know of someone close to them who struggles with the condition, which has increased in prevalence in America an estimated 25% every decade since 1960. Asthma is a chronic disease that affects the airways of the body, leading to increased sensitivity, soreness, and swelling of these inner airways and ultimately less air into the lungs. Common symptoms include but are not limited to; wheezing, cough, tightness of the chest and difficulty breathing. Since there is currently no cure for asthma, the goal of treatment is to relieve these chronic symptoms. This is achieved by avoiding common things that can trigger asthmatic attacks such as exposure to pollen, dander and other allergens and by taking inhaled medications. Inhaled corticosteroids, such as Advair®, are aimed at preventing inflammation and swelling of the airways in a long-term capacity. Other anti-asthmatic medications are inhaled at the time of an asthmatic flare up, with a goal of immediately reducing symptoms. As a whole, the current treatments for asthma are fairly effective; however, many patients still struggle to manage their chronic asthmatic symptoms on a day to day basis.
Fox news recently highlighted a new research study that suggests taking vitamin D may have an influence in combating the chronic effects of asthma.  The idea that vitamin D levels can affect asthma is a fairly common one. Rates of asthma incidence are statistically higher in northern regions, so it appears that there could be a connection between the northern environment and asthma. Many researchers suspect that the decreased sunlight in these regions, which is responsible for producing the majority of the body’s vitamin D, is leading to the increased asthma rates. It is hypothesized that vitamin D helps to protect against asthma by regulating the immune system. This is accomplished by reducing the number of inflammatory cells (Helper T cells) that produce the symptoms of asthma. These inflammatory cells are also thought to produce another negative effect by reducing the effect of inhaled steroids.
The study was performed by Dr. Saba Arshi at the Medical University of Tehran. This study involved one-hundred and thirty children and adults who were diagnosed with mild to severe asthma. The participants were divided into two groups. One group received treatment for their asthma using a dry powder inhaler, the control group, while the other group was treated with both the dry powder inhaler as well as high doses (100,000 units initially and then 50,000 units per week) of vitamin D for six months. After 28 weeks the researchers conducting the study measured the amount of air that patients could exhale. They found that the group who received the vitamin D, along with the inhaler, had improved by about twenty percent, while the dry powder inhaler only group had improved by seven percent.
There were, however, some limitations to this particular study. First, patients’ adherence to the medications was not measured over the course of the study. This means the regularity of the participants actually taking their assigned treatments is unknown. Second, the number of participants in the study was quite small, one hundred and thirty. Finally, the study only measured the volume of air patients were able to exhale, it did not test whether any asthma specific symptoms were improved over the course of the study.
The Fox news article had this to say about the study’s results, “I think it’s a reasonable hypothesis and their study and some other studies provide evidence it might be true. But I don’t think it’s proven yet.”3 This is a fair analysis of the study. Unfortunately, there simply has not been enough testing done on the relationship between vitamin D levels and asthma incidence to make a definitive statement. Much of the research that has been done has shown conflicting results on the topic4. A recent study published in The Journal of the American Medical Association (JAMA) provided results disagreeing with the study previously discussed. The JAMA article tested whether oral vitamin D supplements increased the effect of an inhaled corticosteroid. However, using variables similar to Dr. Arshi’s study, they found that there was no significant difference in treatment when paired with taking vitamin D. Also worth noting is that a recent systematic review, produced by the Journal of Allergy, Asthma and Clinical Immunology, examined 1081 studies. Out of those studies, only three met the systematic reviews criteria and those three all had conflicting results on whether vitamin D levels played a role in Asthma development and treatment.5 This shows that there is still a lot of discussion occurring about the effect of vitamin D in asthma, and further, definitive data is still needed.
However, vitamin D has a wide range of health benefits such as treating conditions that cause weak bones, helping to raise calcium levels in the blood, and treatment of psoriasis, among others. When taken within the recommended daily dose (approximately 600 international units daily depending on age and weight), there are very few side effects traditionally associated with vitamin D. The described study as well as other studies have not been able to present enough evidence to support using vitamin D to treat asthma. However I feel that vitamin D provides such a wide range of benefits, with no major side effects to asthmatics, that it would be worth trying for people struggling with asthma symptoms. Would you be willing to try vitamin D to see what benefits it could have for you or recommend it to asthma patients?
 Brown SD, Calvert HH, Fitzpatrick AM. Vitamin D and Asthma. Dermato-Endocrinology. 2012;2(4):137-145 Accessed September 20, 2014.
 National Heart, Lung and Blood Institute. How is asthma treated and controlled. NIH.gov Web site. http://www.nhlbi.nih.gov/health/health-topics/topics/asthma/treatment.html. Published August 4,2014. Updated 2014. Accessed September 20, 2014.
 Does vitamin D help with asthma? Fox News Web site. http://www.foxnews.com/health/2014/08/19/does-vitamin-d-help-with-asthma/. Published August 19, 2014. Updated 2014. Accessed September 20, 2014.
 Mason R, Sequeira V, Gordon-Thomson C. Vitamin D: the light side of sunshine Eur J Cin Nutr. September 2011;65(9):986-993. Available from: CINAHL Plus with Full Text, Ipswich, MA. Accessed September 20, 2014.
 Rajabbik MH, Lotfi T, Alkhaled L, et al. Association between low vitamin D levels and the diagnosis of asthma in children: A systematic review of cohort studies. Allergy, Asthma & Clinical Immunology. 2014;10(1):1-16.
Therapeutic Research Faculty. Vitamin D. Medline Plus Web site.
 Castro M, King TS,Kunselman SJ, et al. Effect of vitamin D3 on asthma treatment failures in adults with symptomatic asthma and lower vitamin D levels: The Vida randomized clinical trial. JAMA. 2014;311(20):2083-2091. Accessed September 20, 2014
 Therapeutic Research Faculty. Vitamin D. Medline Plus Web site. http://www.nlm.nih.gov/medlineplus/druginfo/natural/929.html. Published July 30, 2014. Updated 2014. Accessed September 20, 2014.