Vitamin D3 is actually not a typical vitamin, but rather a secosteroid hormone that is crucial in upregulating nearly 2,000 out of our approximately 20,000 genes.  It is therefore not just a “nice thing to consider” but rather extremely important in our nearly every aspect of our health. New England’s long winters with limited sun exposure and cabin fever are a major reason for low vitamin D3 levels in our local population. Making matters worse, even if one does get out in the sun on a warmer winter day, the angle of the sun is such that we are getting mostly UVA, and not UVB rays. It is the equivalent of early morning or late afternoon summer sun in that  they have limited impact on elevating our D3 levels. 

While there is some controversy about how much is enough when it comes to blood levels and dietary and supplemental intake, one thing is very clear, we all need to find out our levels and work from there in order to optimize them. The standard medical recommendation of anything between 30 and 100 mcg/dl blood level being within normal limits is thankfully being revised as researchers are moving in the direction of 50-70 mcg/dl being a much better goal.  In many emergency rooms around the world (according to John Cannell, MD-originator of the Vitamin D Council) anyone presenting with chest pain or anything that looks like a heart attack, are injected with 100,000 IUs of vitamin D3,

 Dietary sources such as egg yolks, liver oily fish and butter are not on everyone’s diet and actually pale in comparison to taking an inexpensive supplemental form of D3 made from lanolin.  Plant based foods like mushrooms contain D2 and the body has to work harder to convert it into D3.

A precursor of vitamin D3 lives in our skin and is converted to D3, upon exposure to ultraviolet B (UVB) light.  It has been estimated that one hour of middle of the day sun exposure at the latitude of Cape Cod in late July and early August, will produce about 20,000 IUs (International Units) of D3 in an average adult in a bathing suit. D2 is then converted to D3 in the body over the course of a few to several hours. Understandably, this fat soluble compound then sits in the skin for a while before it is absorbed so please delay your soapy shower after coming home from the beach this summer.    

The darker the pigmentation of one’s skin, the greater the amount of exposure necessary to generate a healthful level. This makes perfect sense when one considers pigmentation differences between populations native to equatorial areas versus much higher latitudes. The closer to the equator, the greater the percentage of sunlight in the form of UVB versus UVB and the greater the length of exposure.  The closer to either of earth’s poles one lives, the shorter the day and the lower the percentage of UVB.

Current research has implicated vitamin D3 deficiency as a major factor in the pathology of at least 17 varieties of cancer as well as heart disease, stroke, hypertension, autoimmune diseases, diabetes, depression, chronic pain, osteoarthritis osteoporosis, muscle weakness, muscle wasting, birth defects, periodontal disease and more. 

Vitamin D3’s influence on key biological functions vital to one’s health and well-being mandates that vitamin D3 no longer be ignored by the health care industry nor by individuals striving to achieve and maintain a greater state of health.

While it may be possible for one to over-supplement and elevate their blood level too high, a routine quarterly or semi-annual blood test can prevent that from happening.  The pharmaceutical world offers 50,000 units of D2 to be taken once weekly when a blood test confirms low levels.  I personally believe that D3 is the better option and it should be taken daily in the fall, winter and spring.

We don’t often get summertime colds or flu viruses in large part, due to naturally elevated D3 levels in the summer.  The key is getting outside and exposing some skin, even face, arms and legs in the middle of the day, avoiding burns by limiting exposure time until the skin feels prickly and perhaps by supplementing with carotenoids like astaxanthin.

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