Vitamin D is important for calcium and bone metabolism, gut and mucosal lining protection and immune response. Vitamin D deficiency is worldwide, especially in the elderly population (2).
Vitamin D and Bones
Vitamin D3 helps your bones absorb calcium and phosphorous. This makes bones strong. When taken with vitamin K2, D3’s actions are increased. What’s more is the help vitamin D supplies to muscle status: “Cochrane analysis found that vitamin D supplementation in care home residents reduced the rate of falls by 27% [rate ratio, 0.63 (95% CI: 0.46, 0.86); 5 trials, 4603 participants]” (2).
Vitamin D and the Gut
Vitamin D is responsible for pulling the gap junctions, or spaces between the cells lining the gastrointestinal tract. It helps heal and prevent leaky gut, inflammatory bowel disease and may even help reduce risk for colorectal cancer. It also helps promote a healthy microbiome, especially those microbes that make the B vitamins for you(1).
Vitamin D and the Immune
Vitamin D reduces severity of respiratory tract infections. Specifically, it tightens mucosal barriers which protects us from infection, it has the ability to kill enveloped viruses, reduces cytokine production, and reduces risk of a cytokine storm.
We do see a number of people with chronic disease more susceptible to COVID-19, and traditionally those with chronic disease have low stores of Vitamin D. In line with this, a number of small studies show trends that support the thought that low levels of Vitamin D increase risk of severe reactions to COVID-19. Collection of data continues as these limited, small, non-ethnically diverse observational patient data does not provide us a direct cause and effect.
How much Vitamin D do you need?
In Ontario, the government assumes everyone is deficient and needs to supplement, that’s why OHIP no longer pays for the test. Supplementation of 1000IU per day is generally prescribed, you may need more or less and too much can be harmful, so be careful. A baseline lab test around (around $60 available through your MD or ND) every year or two helps direct what dose you best take. In all, we need to pay attention to our levels of vitamin D. Vitamin D levels are measured in ng/ml or nmol/l (1 ng/ml is equivalent to 2.5 nmol/l). In Canada, 25-250 mol/L is the range for health. It is individual, but we generally like to see the levels around 120nmol/L.
For those living in the geographical latitudes of Canada, about 1000IU is made in the body with twenty minutes of unprotected skin in mid-day sunlight between May and September. More time in the sun has its drawbacks; skin cancer is the most diagnosed cancer in Canada. Fatty fish like salmon and mackerel as well and beef liver and egg yolks, naturally have a small amount of Vitamin D3.
Vitamin D is a fat-soluble vitamin, so you store it up in your body in the summer months and draw on your stores in the winter. Your levels will be at their lowest in the spring time, especially if you do not supplement.
Disclaimer: Information in this post is provided for informational purposes only. This information is not intended as a substitute for the advice provided by a registered naturopathic doctor or other healthcare professional.
Ref: (1)Gominak S. C. (2016). Vitamin D deficiency changes the intestinal microbiome reducing B vitamin production in the gut. The resulting lack of pantothenic acid adversely affects the immune system, producing a “pro-inflammatory” state associated with atherosclerosis and autoimmunity. Medical hypotheses, 94, 103–107. https://doi.org/10.1016/j.mehy.2016.07.007
(2)Sahota O. (2014). Understanding vitamin D deficiency. Age and ageing, 43(5), 589–591. https://doi.org/10.1093/ageing/afu104