The Los Angeles Times “Booster Shots” blog reported that researchers at the National Jewish Health in Denver found that “adult asthma patients with the highest levels of vitamin D in their blood had better lung function compared with people with the lowest levels” in a study published in the American Journal of Respiratory and Critical Care Medicine.
“For every 1-ng/mL increase in serum levels of 25-hydroxyvitamin D (25-OH-D), forced one-second expiratory volume (FEV1) increased by 21 mL,” MedPage Today reported. The 54-patient study “also showed that airway hyperreactivity in those with serum 25-OH-D levels below 30 ng/mL — defined as vitamin D insufficiency — measured at almost twice the average levels seen in those with normal levels of 25-OH-D.”
“Low vitamin D levels were also associated with a worse response to steroid therapy and increased production of the pro-inflammatory cytokine, TNF-alpha,” HealthDay reported. “This raises the possibility that low vitamin D levels are tied to increased inflammation of the airways.” Nothing that the “heaviest participants had the lowest levels of vitamin D,” the authors say that the “(lack of vitamin D) may be a factor linking” obesity and asthma.
WebMD quotes lead investigator E. Rand Sutherland, MD, MPH, as saying, “The next question to answer is whether giving supplemental vitamin D will lead to clinical improvements in patients with asthma.”
However, given the incredible safety of vitamin D supplements, combined with how very inexpensive these supplements are, pending further data, I’ll be offering all of my asthmatic patients two options: (1) test their blood vitamin D level and use supplements in anyone with a level below 40, or (2) just take 800-1000 IU of vitamin D per day as a supplement.
Here are some of my other blogs on vitamin D:

• Vitamin D deficiency in kids is getting more attention
• Heart patients lacking vitamin D more likely to be depressed
• Alarm Sounded on Childrens’ Lack of Vitamin D
• Study suggests 70 percent of children, young adults do not get enough vitamin D
• More reasons to consider having your vitamin D level checked – you may think better and have less arthritis
• Specific vitamins and a supplement (B vitamins, vitamin D, and calcium) may lower risk of stroke, blindness, and cancer
• Vitamin D tests soar as deficiency, diseases linked
• Lack of vitamin D raises death risk
• Vitamin D Recommendations for Teens May Be Too Low
• Vitamin D may protect against heart attack
• Low Vitamin D Levels Associated with Artery Disease