Confirmed: Vitamin D Protects Against Colds and Flu

Recent research proves that vitamin D guards against colds, the flu and other respiratory illnesses. A daily dose of vitamin D supplements is especially helpful in the quest to fend off sickness. However, even a weekly dose of vitamin D will help in the prevention of colds and the flu. Those who are deficient in vitamin D will especially benefit from a regular dose of this incredibly helpful vitamin. Vitamin D is currently prescribed by physicians for an array of ailments.

Details of the Global Collaborative Study

A team of researchers from around the world determined vitamin D supplements combat the onset of numerous respiratory diseases. Carlos Camargo from Massachusetts General Hospital's Department of Emergency Medicine served as the study's senior author. The research was funded through a grant provided by the United Kingdom's National Institute of Health Research. The worldwide collaborative study confirms that vitamin D supplements help ward off acute respiratory infections.

The study consisted of a meta-analysis of 25 randomized trials with over 11,000 participants. The study's details and results were recently published on the web in The BMJ. It is widely known that vitamin D is vital for muscle and bone health. However, it was unclear as to whether vitamin D played a critically important role in combating acute respiratory infections. Such infections result in millions of hospital visits and deaths across the world each year.

Clearing up Conflicting Data

A handful of observational studies that monitored patients across time without implementing a specific treatment had linked low levels of vitamin D to a higher susceptibility of acute respiratory infections. Several clinical trials have also been conducted to study vitamin D supplements' protective ability. Some of these studies determined the vitamin really does provide a protective quality. However, some studies showed that it does not have any protective effect. Meta-analyses performed of these clinical trials aggregated information from numerous studies that have differing designs and/or participant qualifications produced conflicting results.

The global research team referenced above cleared up these conflicting results. Queen Mary University of London's Adrian Martineau led the team. He performed a data meta-analysis of individual participants from over a dozen nations. Participants hailed from the United Kingdom, the United States, Canada and beyond. Prior meta-analyses pit average data from subjects in each study. Alternatively, individualized data meta-analysis distinguishes data from each participant, generating what is considered as a higher-resolution analysis of information across all studies.

The Results

It was determined that weekly and daily vitamin D supplements provided the optimal benefit for those who suffered from a severe vitamin D deficiency. This deficiency is defined as a blood level with 10 mg/dl or less. Vitamin D supplementation reduced the odds of a respiratory infection by one-half for such individuals suffering from a vitamin D deficiency. The study also found that every single participant enjoyed at least a minor benefit from consuming vitamin D supplements on a regular basis. It is worth noting that consuming occasionally high doses of the vitamin did not generate extensive benefits.

The hope is that people will ramp up their consumption of vitamin D supplements to reduce the risk of colds, the flu, and other respiratory maladies. This course of preventative action would prove especially helpful for those who are vitamin D deficient. Such supplementation would reduce the number of emergency department visits, which currently number in the millions. As a result, the health system would be less burdened. Furthermore, the study's findings might inspire food manufacturers to fortify foods with vitamin D. Such a measure would prove especially beneficial to those who are deficient in vitamin D.