The vitamin comes in two forms: D2 from diet and D3, which can be produced in skin when exposed to sunlight.
Why are Americans lacking vitamin D, a fat-soluble vitamin that functions like a steroid hormone?
When I was attending Mission Elementary School on the Rosebud Reservation in South Dakota, we lined up every day to receive a tablespoon of cod liver oil (high in vitamin D). Then, staying in line, we walked down to the lunchroom and drank a glass of milk, fortified with vitamin D. Only then were we allowed outside to play.
There was a health crisis on the Reservation in the 1950s and it was felt these simple preventative steps would prevent rickets, a disorder that causes children to have bones that are weak and soft, caused by a lack of vitamin D. Were school administrators/Bureau of Indian Health Care (now the Indian Health Service) onto something about Vitamin D?
The Wall Street Journal’s November 3 story (“Can Vitamin D Help Fight Coronavirus?”) cited a JAMA article centered on Chicago Covid-19 patients. It showed the risk of testing positive for the disease was 1.77 times higher for people with a deficiency compared with those with adequate levels of vitamin D.
Back in 2010, a National Institutes of Health story (“Vitamin D – An Ignored Epidemic”) noted that “Current research indicates vitamin D deficiency plays a role in causing seventeen varieties of different cancers as well as heart disease, stroke, autoimmune diseases, birth defect, and periodontal disease.”
Studies show that people with darker skin, such as African Americans and Latinos, are at risk because high amounts of melanin in skin reduce the body’s ability to produce vitamin D from sunlight. Additionally, now even Caucasians who wear sunscreen are in danger of being deficient in the vitamin.
Foods that are high in vitamin D include fortified milk, yogurt and orange juice; fortified breakfast cereals; eggs; fatty fish such as salmon, tuna and sardines; pork chops and grilled portabella mushrooms.
According to the Cleveland Clinic, “Getting enough vitamin D may also play a role in helping to keep you healthy by protecting against the following conditions and possibly helping to treat them: heart disease and high blood pressure, diabetes, infections and immune system disorders, multiple sclerosis, falls in older people, some types of cancer, such as colon, prostate and breast cancers.”
In the WSJ story, Roger Bouillon, emeritus professor in endocrinology at the University of Leuven in Belgium and one of the authors of a pilot study in Cordoba, Spain, suggests that vitamin D be used to treat Covid. There patients hospitalized with Covid were treated with a high dose of calciferdiol, a derivative of Vitamin D.
Bouillon said, “I could make a list of 50 diseases: If you are D deficient, then you have a higher risk of all these diseases but that’s an association and doesn’t prove anything about causality.”
According to the Cleveland Clinic, symptoms of Vitamin D deficiency might include mood changes, bone loss, muscle cramps (or weakness), bone and joint pain (especially in the lower back) and fatigue.
According to Healthline, there are seven common risk factors for Vitamin D deficiency:
1) having dark skin
2) being elderly
3) being overweight or obese
4) not eating much fish or dairy
5) living far from equator where there is little sun year-round
6) always using sunscreen when going out
7) staying indoors
Why would obesity be an issue? According to the National Institutes of Health, those who have a body mass index of 30 or more have lower levels of Vitamin D because “The greater amounts of subcutaneous fat sequester more of the vitamin. Obese people might need greater intakes of vitamin D to achieve levels similar to those of people with normal weight.”
Vitamin D helps with the absorption of calcium, which not only helps build bones, but keeps them strong and healthy. Weak bones can lead to osteoporosis, the loss of bone density, which can lead to fractures.
CNET in an April 2020 story (“Vitamin D Is Crucial for Immune Health—Make Sure You’re Getting Enough”) wrote: “Research shows that vitamin D plays an important role in immune function, and a deficiency in it is shown to increase your susceptibility to infection.
“‘Some studies have shown that vitamin D deficiency is even associated with greater risk of self-reported upper respiratory tract infections,”” said Jacyln Tolentino, a physician at Parsley Health in L.A. Further, “low serum levels of calcidiol [a form of vitamin D] are also associated with higher susceptibility to infections like tuberculosis, influenza, and viral infections of the upper respiratory tract.'”
According to the Healthline (“Can Vitamin D Lower Your Risk of Covid-19?”) vitamin D is necessary for the proper functioning of a body’s immune system. “This vitamin plays a critical role in promoting immune response,” the article said. “It has both anti-inflammatory and immunoregulatory properties and is crucial for the activation of immune system defenses.
“Vitamin D is known to enhance the function of immune cells, including T cells and macrophages, that protect your body against pathogens.
“In fact, the vitamin is so important for immune function that low levels of vitamin D have been associated with increased susceptibility to infection, disease and immune-related disorders.”
(Editor’s note: The deficiency is common, but most people are unaware of it unless they have yearly physical exams. If you think you may have a deficiency, it is important that you speak to your doctor and get your blood levels measured.)