says Michael F. Holick, PhD, MD, at the Boston University School of Medicine. “Studies done here and abroad since the start of the pandemic have found that the risk of getting the virus and dying from it is far greater in individuals with suboptimal levels of vitamin D. Those at the highest risk for COVID-19-the elderly, people who are obese and people of color-also are at a greater risk of being vitamin D-deficient.” COVID-19 has been added to the long list of ailments that are closely connected to a vitamin D deficiency. Because of its important role in the immune system, having a vitamin D deficiency leaves you more vulnerable to a host of diseases, including heart disease, type 1 diabetes, multiple sclerosis, rheumatoid arthritis, respiratory infections, inflammatory bowel disease, and breast and colon cancer.

One of vitamin D’s main strengths is in its ability to reduce inflammation in cells throughout the body, such as the prostate, breasts, skin, intestinal tract, blood vessels, brain, as well as immune cells. Vitamin D has the ability to exert a positive influence on many aspects of your health.

According to the Endocrine Society, vitamin D status is broadly described in one of three ways:

Deficiency: A blood level of 25-hydroxyvitamin D below 20 nanograms per milliliter (ng/ml) causes bone disease and increases risk for the above mentioned diseases.

Insufficiency: A blood level between 21 ng/ml and 29 ng/ml- the minimum for bone health but lacking for protection of the other diseases.

Sufficiency: A blood level of 30 ng/ml to 100 ng/ml.

Dr. Horlick goes on to say that it may be better to aim for an optimal blood level between 40 ng/ml and 60 ng/ml, which is considered the preferred range.

About 80% of people with COVID-19 are vitamin D deficient, and numbers in the general population could be just as high, so we could all benefit from getting more vitamin D. It’s hard to get enough vitamin D from foods, even fortified ones. The sun is the best source. However, even people in sunny areas (like myself) may be deficient due to sunscreen or avoiding sun exposure for vitamin D production (between 10 am and 3 pm). Luckily, there are high-quality over-the-counter supplements that can boost D levels. The best is D-3 (for vegans D-2). Dr. Horlick recommends that children get 1000 IU daily, teenagers and adults at least 2000 IU daily.

Personally, I take 5000 IU daily, and my levels are within the optimal range. A simple blood test can indicate what level you are at. Vitamin D is inexpensive, and taking it daily gives me less health concerns to worry about.

Stay well,

John R Blilie, MS, OSC