If you’ve repeatedly fallen for this annual propaganda campaign, you may be surprised to find the medical literature suggests vitamin D may actually be a FAR more effective strategy, and the evidence for this goes back at least a decade.
Dr. John Cannell, founder of the Vitamin D Council, was one of the first to introduce the idea that vitamin D deficiency may actually be an underlying CAUSE of influenza.
Vitamin D protects against colds and flu, finds major global study
Overall, the studies included nearly 11,000 individuals from more than a dozen countries. As reported by Time Magazine:7
People who took daily or weekly vitamin D supplements were less likely to report acute respiratory infections, like influenza or the common cold, than those who did not …
For people with the most significant vitamin D deficiencies (blood levels below 10 [ng/mL]), taking a supplement cut their risk of respiratory infection in half.
People with higher vitamin D levels also saw a small reduction in risk: about 10 percent, which is about equal to the protective effect of the injectable flu vaccine, the researchers say.”
Like Cannell before them, the researchers believe vitamin D offers protection by increasing antimicrobial peptides in your lungs, and that “[t]his may be one reason why colds and flus are most common in the winter, when sunlight exposure (and therefore the body’s natural vitamin D production) is at its lowest …”8
According to this international research team, vitamin D supplementation could prevent more than 3.25 million cases of cold and flu each year in the U.K. alone.9 Another statistic showing vitamin D is a more effective strategy than flu vaccine is the “number needed to treat” (NNT).
Sun exposure is the ideal way to optimize your vitamin D.
Most people understand that vitamin D is critical for bone and muscle health,” said Carlos Camargo, MD, DrPH, of the Department of Emergency Medicine at Massachusetts General Hospital (MGH) and the study’s senior author. “Our analysis has also found that it helps the body fight acute respiratory infection, which is responsible for millions of deaths globally each year.”
The study provides the most robust evidence yet that vitamin D has benefits beyond bone and muscle health, and could have major implications for public health policy, including the fortification of foods with vitamin D to tackle high levels of deficiency in the UK.
The results, published in the BMJ, are based on a new analysis of raw data from around 11,000 participants in 25 clinical trials conducted in 14 countries including the UK, USA, Japan, India, Afghanistan, Belgium, Italy, Australia and Canada. Individually, these trials yielded conflicting results, with some reporting that vitamin D protected against respiratory infections, and others showing no effect.
Research suggest optimizing your vitamin D levels is one of the absolute best flu-prevention and optimal health strategies available.
Lead researcher Professor Adrian Martineau from QMUL said: “This major collaborative research effort has yielded the first definitive evidence that vitamin D really does protect against respiratory infections. Our analysis of pooled raw data from each of the 10,933 trial participants allowed us to address the thorny question of why vitamin D ‘worked’ in some trials, but not in others.
“The bottom line is that the protective effects of vitamin D supplementation are strongest in those who have the lowest vitamin D levels, and when supplementation is given daily or weekly rather than in more widely spaced doses.
“Vitamin D fortification of foods provides a steady, low-level intake of vitamin D that has virtually eliminated profound vitamin D deficiency in several countries. By demonstrating this new benefit of vitamin D, our study strengthens the case for introducing food fortification to improve vitamin D levels in countries such as the UK where profound vitamin D deficiency is common.”
Vitamin D – the ‘sunshine vitamin’ – is thought to protect against respiratory infections by boosting levels of antimicrobial peptides – natural antibiotic-like substances – in the lungs. Results of the study fit with the observation that colds and ‘flu are commonest in winter and spring, when levels of vitamin D are at their lowest. They may also explain why vitamin D protects against asthma attacks, which are commonly triggered by respiratory viruses.
Daily or weekly supplementation halved the risk of acute respiratory infection in people with the lowest baseline vitamin D levels, below 25 nanomoles per litre (nmol/L). However, people with higher baseline vitamin D levels also benefited, although the effect was more modest (10 per cent risk reduction). Overall, the reduction in risk of acute respiratory infection induced by vitamin D was on a par with the protective effect of injectable ‘flu vaccine against ‘flu-like illnesses.
Acute respiratory infections are a major cause of global morbidity and mortality. Upper respiratory infections such as colds and ‘flu are the commonest reason for GP consultations and days off work. Acute lower respiratory infections such as pneumonia are less common, but caused an estimated 2.65 million deaths worldwide in 2013. Vitamin D supplementation is safe and inexpensive, so reductions in acute respiratory infections brought about by vitamin D supplementation could be highly cost-effective.
The study was conducted by a consortium of 25 investigators from 21 institutions worldwide, and funded by the National Institute for Health Research (NIHR).
Professor Hywel Williams, director of the NIHR Health Technology Assessment (HTA) Programme said: “The interesting findings of this large study are worthy of serious further debate. This study is yet another example of how the NIHR HTA Programme reaches the parts that other research funders may not tackle.”
Credit: Queen Mary University London