We’re heading into the Christmas holidays, where parties, friends, and family abound, and gifts and hugs are shared. Unfortunately, these close quarters are also prime opportunities for the flu and other viruses to be shared among us. If our immune systems are compromised with our lack of sunlight at this time of the year (and therefore low Vitamin D), and further taxed by lack of sleep, stress, alcohol, sweets, dry heated environments, and lack of exercise, we can be more susceptible to coming down with the flu.
So what’s the scoop on Vitamin D, and can it help you prevent and/or treat the flu?
Low Vitamin D levels are associated with higher flu rates.
There are many studies showing that deficient levels of Vitamin D are associated with higher rates of flus and respiratory tract infections. Now, keep in mind that just because there is a correlation, it doesn’t mean that the lack of Vitamin D is actually causing the increase in flus, and it’s definitely not the only factor. But clinically, we do see that optimizing Vitamin D levels and correcting deficiencies generally decreases patients’ frequency of getting sick with the flu.
Vitamin D supplementation has been studied in the context of preventing one kind of influenza, influenza A. It was found that supplementing with Vitamin D decreased influenza A flus in schoolchildren, with the added bonus of decreasing asthma rates in those susceptible (Urashima et al., 2010).
Optimize Your Vitamin D Levels
I frequently test my patients for their Vitamin D levels in the blood (25-0H Vitamin D), and very rarely are they adequate, even in those that are taking 1000-2000 IU of vitamin D on a daily basis! So often, if your levels were very deficient to start with, blindly taking the recommended intake won’t help very much. You also don't want to take too much and overdose!
The average blood level of Vitamin D in Canadians is below 75 nmol/L (the lower end of the “normal” range), and 1/3 of those people are likely quite deficient, with levels below 50 nmol/L. Levels in the winter are even lower than that! I aim not only for normal ranges, but optimal ranges for my patients. This usually requires prescription level doses of Vitamin D (>1000 IU a day), which I can prescribe. Getting your levels checked can allow me to dose your Vitamin D appropriately and safely, bringing your levels up quickly and efficiently. Vitamin D is also important for so many other things, including bone health, mood, and energy!
Treatment Of Flu With “The Vitamin D Hammer”
Most of us have come down with the flu at some point or another, and we know it can make us feel quite miserable. What if you could cut that misery short? Can Vitamin D help once you already have the flu?
There isn’t much research in the area. However, there is some evidence clinically from doctors who use high doses of Vitamin D that it can be very helpful. We’re not talking about 800-1000 IU a day in these instances, as this likely would be too little, too late for most people. Dr. Gerry Schwalfenberg, MD, and his colleague use very high doses of Vitamin D (we’re talking high prescription doses) at the onset of the flu for 2-3 days. They call this “the Vitamin D hammer”, flooding the body with Vitamin D short-term! With this protocol, they find that patients’ symptoms resolve within 48-72 hours, which is amazing considering that the usual flu will often last a week or more, and can be followed by feeling weak and rundown for a while still afterwards.
Do you want to minimize your chances of getting the flu? Then among your arsenal, a good personalized dose of Vitamin D would probably be a good idea. We can get you tested to optimize your levels, and include other immune-boosting measures and supplements into your treatment plan so that you keep up your energy and smile all winter long!
Schwalfenberg G. (2015). Vitamin D for influenza. Can Fam Physician, 2015 Jun; 61(6):507. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4463890/
Urashima M., Segawa T., Okazaki M., Kurihara M., Wada Y., and Ida H. (2010). Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren. Am J Clin Nutr, 2010 May;91(5):1255-60. doi: 10.3945/ajcn.2009.29094. Epub 2010 Mar 10.
Dr. Tamar Ferreira is a Naturopathic Doctor in Brampton, Ontario. Her areas of focus include digestive health, hormone balance, and skin conditions.