Worried About the Flu? Vitamin D Might Help

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During this brutal cold and flu season, everyone is looking for ways to keep their immune system up and running with good hygiene, healthy diets, and herbal support. But don't forget about the sunshine vitamin. Here's what the science says about the important role vitamin D plays for immune health.

— Tieraona Low Dog, M.D.

Winter is full upon us and this season’s flu is making headlines. The nightly news is filled with stories of hospitals being overwhelmed by patients due to this year’s nasty flu virus, and other respiratory infections that are also a major cause in the uptick in doctors visits. Both illnesses seem exceptionally bad this year, and mainstream media is calling on people to get the flu vaccine, even though admittedly it is not as effective as one would hope. 


It’s important to remember that severe respiratory tract infections and the flu aren’t to be taken lightly. My great-grandfather died in 1918 from the “Spanish flu” that killed more than 20 million people worldwide that year. These infections are responsible for roughly 2.6 million deaths worldwide each year. While the flu vaccine can give you an edge, and in some years, it is highly effective, there might be something else you can do protect you and your family. 


Keep Taking Your Vitamin D!


Vitamin D is a fascinating piece of the human health puzzle. It actually behaves more like a hormone than a vitamin, and it plays a powerful role in the health of our immune system. In fact, your vitamin D levels can be a good indicator of your overall health.  


I, like many other experts, believe the recommended daily amount of 600 IU is far too low. In the United States, 90 million Americans have serum levels of vitamin D less than 20 ng/ml (50 nmol/L), which simply isn’t enough. The Endocrine Society recommends a level of 30 ng/ml (75 nmol/L) or higher for everyone.  To keep the flu away and to stay healthy this year, I think it’s smart for most of us to supplement with 1000-2000 IU vitamin D3 per day. You should take your vitamin D with a fatty meal to enhance absorption.


Let’s take a closer look at why vitamin D could be an important factor in keeping the flu away this year. 


The Wonderful Benefits of Vitamin D


A recent extensive meta-analysis and systematic review published in the prestigious British Medical Journal says one approach to preventing acute respiratory tract infections is vitamin D. 


Researchers found after reviewing 25 randomized controlled trials including roughly 11,000 participants, that daily or weekly vitamin D supplementation showed an overall protective effect against acute respiratory tract infection. 


While everyone garnered some benefit, those who had the lowest vitamin D levels experienced the greatest positive impact from supplementation. Interestingly, those who took large boluses of vitamin D (100,000 IU once per month for example) did not receive the same protection.


This analysis confirms what other studies have found: that the impacts of vitamin D are widespread. Other health benefits of vitamin D include: 


  • Alleviating irritable bowel syndrom
  • Improving gut health
  • Promoting good digestion
  • Boosting brain function


Vitamin D has even been associated with a lower risk of death from all causes. 


Sounds almost too good to be true, doesn’t it? A meta-analysis of 50 studies that included 94,148 participants found that vitamin D – specifically vitamin D3, was associated with a reduced risk of disease and death. 


Vitamin D is so great for your health; the government began fortifying milk with it in 1932 (vitamin D2). Though getting your vitamin D through food and supplements is probably not as efficient as when your body creates it after sun exposure, it’s important to ensure you are getting enough, no matter the source, especially during the winter months when there is less sun. 


Who’s at Risk for Low Vitamin D Levels?


The number one source of vitamin D is the sun. That being said, the many common risk factors for low vitamin D levels have to do with ability or likelihood to absorb sunlight. Those at a higher risk for low vitamin D levels include:


  • People with darker skin
  • Those who are overweight/obese
  • Being older
  • Those who work inside
  • Vegetarians and vegans
  • Those who aren’t eating a nutrient dense diet
  • Having kidney impairment
  • Those who wear too much sunscreen or always cover up when outside
  • Living in higher altitudes
  • Living in a city with a lot of smog
  • Living in a place with long winters
  • Living in an area with cloudy weather



The reason so many of us get sick during the winter month may be due in part to the lack of vitamin D. 



Symptoms Of Low Vitamin D Levels


There are vitamin D receptors all over your body, which causes the symptoms of low vitamin D levels to appear widespread. Some symptoms of low vitamin D levels include:


  • Becoming sick frequently
  • General malaise
  • Exhaustion or fatigue
  • Chronic pain
  • Joint or bone pain
  • Depression
  • Weakness
  • Digestive issues
  • Brittle bones
  • Excessive sweating
  • Hair loss


Vitamin D and Your Best Health


You can ask your healthcare practitioner to test your vitamin D level, or you can order your own 25-hydroxycalciferol (25(OH)D) test through requestatest.com for about $60.   But for most of us, taking 1000-2000 IU of vitamin D3 each day is safe and beneficial for keeping our blood levels healthy.  Supplementing with vitamin D3, as opposed to D2, is considered more effective and more easily used by your body. 


It’s important to work on the body as a whole.


This winter be extra good to yourself. Eat more wholesome, nutrient-dense foods, take healing herbs, wash your hands frequently, and of course supplement with vitamin D3.  Take care of yourself and give your body the best fighting change it has against illness. 


Share this article with a friend or family member who would benefit from learning about the power of vitamin D!