The Dirt on D.
“Worldwide, an estimated 1 billion people have inadequate levels of Vitamin D in their blood. ”
Vitamin D is technically not a vitamin — it’s a hormone, and a darn important one at that.
Its role is to help the body absorb and retain calcium. Our bodies can actually make vitamin D, mostly from sun exposure and to a smaller extent, our diet. With increased indoor lifestyles in our computer age and wide use of sunscreens, large segments of the population are now suffering from Vitamin D deficiency.
Not only is Vitamin D associated with calcium regulation, but this relationship also plays a commanding role in maintaining both health, boosting immunity, and combating many disease processes, including diabetes and some forms of cancer. Vitamin D’s role at warding of infection has even made it a particularly interesting point of research in Covid-19 prevention.
““The rate of severe deficiency was much higher in most population groups than we would have expected, so these results are very alarming.””
With the sun’s rays on bare skin being responsible for some 90% of our Vitamin D, many countries situated in northern latitudes have suffer from lower overall Vitamin D levels within their populations. Those in lower socioeconomic communities and those with greater melanin (darker skin) are disproportionately represented in Vitamin D deficient populations — in some cases as much as 80% of the population. Worldwide, nearly 1 billion people have inadequate Vitamin D levels.
Currently, the Public Health of England recommends around 15 minutes a day of sun exposure, when it is comfortable to do so, in warmer temperatures. Ultraviolet - B, or UVB (the type that can burn the skin), is responsible for Vitamin D in our bodies.
With increased health concerns over sun exposure, there has been increased interest in dietary methods of boosting Vitamin D levels. Foods that are naturally high in Vitamin D are certain oily fish (salmon, sardines, herring, and fish liver oils). It turns out that your grandmother was right that cod liver oil would ward off illness.
For Vitamin D supplements, there are two main varieties: Vitamin D2 (ergocalciferol) and D3 (cholecalciferol). When you buy supplements, the fine print will often tell you which variety is in the capsule. D2 is typically from plants and D3 is usually from animal sources. Many studies have debated which one is best, but D3 may have a slight edge at maintaining blood concentrations of Vitamin D. The Harvard School of Public Health recommends not exceeding 4000 IU of Vitamin D daily without doctor supervision.
Fortunately, many cod liver oil capsules, fish oils, and Vitamin D capsules need not be refrigerated, making them excellent for travel. In addition, a diet rich in low-mercury fish (like herring and sardines) also adds Vitamin D benefit. Yet, nothing beats the sun. Getting short bouts of sun exposure on bare skin while being mindful of UV intensity and duration, not only elevates Vitamin B levels, but is mentally uplifting as well.
This article does not constitute medical advice. Always seek the opinion of a medical professional before starting a nutrition or fitness program.