Vitamin D Supplementation & Our Immune Systems

As we move deeper into the winter months, and holiday eating, our immune systems tend to struggle and flail to fight off  colds and flus.  Some of our immune systems are able to outwit the critters, and some are not.  There is a lot of attention and marketing geared towards ‘immune support’ and what actually contributes to a strong immune system, and what behaviors or supplements truly confer protection.  Among these immune supportive strategies is Vitamin D supplementation, which has been getting quite a bit of press in the past few years as the latest immune tonic. 

Primarily, the active form of Vitamin D is made in the skin in response to UV exposure.  However, in the winter months, our days and our time outside get shorter.  We are exposed to much less UV stimulation during the winter months, and at some latitudes (such as the Seattle area at 47 degrees N) not at all.  As such, we make less Vitamin D during this time of year and the only way to get what we need is via supplementation. 

There have been many studies demonstrating its positive effects on our immune systems including breast and colon cancer prevention.  Part of how this works is that active Vitamin D ‘turns on’ the part of our immune system that keeps a lookout for viruses or other cells that can cause illness. 

Additionally, it decreases inflammation via this same part of the immune system, with our T-cells.  It is the inflammatory process itself that we call a ‘cold’ or ‘flu’.  The symptoms we recognize as fever, chills, mucous, and fatigue are our body fighting off the critters, which is the inflammatory process that our body creates to boil ’em up and kick ’em out.  Rather than fully shutting this process off, Vitamin D helps this process to be more efficient and fine-tuned. 

Potentially, Vitamin D supplementation (in the absence of naturally-made Vitamin D due to UV exposure) may not only improve our body’s initial defense but also decrease the severity of what we experience when we do get sick. 

I attached this link to a recent study regarding Vitamin D and its use in Type 1 Diabetes Mellitus to address this concept of ‘decreased inflammation and severity’, as well as food for thought about how Vitamin D may work in blood sugar management overall.

Type 1 Diabetes, unlike Type 2 which many of are familar with, is an autoimmune condition.  This means that the body and immune system is essentially attacking itself.  If we can use Vitamin D therapeutically to affect the way our immune system overreacts and attacks our own bodies, we can also use it to minimize what we experience when our immune system reacts to and fights back against critters. 

For many of us, the first step is having Vitamin D levels tested.  If your practitioner is not familiar with the test, request to have your serum 25-OH Vitamin D levels screened with your next round of routine blood work.  Although the labs have different ranges for what is ‘normal’, having a Vitamin D level over 50 ng/mL is considered optimal for the desired immune function.  If your levels are lower than that, discuss appropriate supplementation and food sources with your provider.  Generally speaking, adults benefit from 2000-4000 IU daily and kids benefit from 400-1000 IU daily, but it depends on your levels, time of year, and other health concerns to pick just the right dose for you and your family. 

Here’s to having a healthy winter season! 

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