Dr. Bowen on the importance of Vitamin D and why you should care.
What is Vitamin D?
A steroid vitamin which promotes the intestinal absorption and metabolism of calcium and phosphorus. Under normal conditions of sunlight exposure, no dietary supplementation is necessary. Deficiency can lead to bone deformity (rickets) in children and bone weakness (osteomalacia) in adults. Deficiency is also being implicated as a potential cause of many other common diseases. Vitamin D is not technically a vitamin, but rather behaves more like a hormone and has countless important actions in the body.
Where do we get Vitamin D?
The most notable options for getting Vitamin D are from the sun, from artificial UVB light and from supplements. Only trace amounts are available from the diet (eggs, fish and dairy). The process of making Vitamin D in the body begins when the sun’s Ultraviolet B radiation (UVB) reacts with our skin. Once Vitamin D is produced in the skin or consumed, it is converted in the liver and kidney to form 1,25 dihydroxy Vitamin D, the physiologically active form of Vitamin D. Following this conversion, the hormonally active form of Vitamin D is released into the circulation where it binds to a carrier protein in the blood stream and is transported to various target organs.
Why is it so Important?
Historically, Vitamin D deficiency has been linked to bone diseases as stated above. In more recent literature, Vitamin D deficiency has been linked to many illnesses including cancer (especially prostate and breast), multiple sclerosis, heart disease, autism, diabetes and even the common cold or flu. Its final metabolic product helps with repair and maintenance of more than 200 human genes in a variety of tissues. One of the many genes that it helps to influence is a naturally occurring (in the body) broad-spectrum antibiotic. Our understanding of Vitamin D’s importance is still in its infancy. Stay tuned!
What are the risk factors for Vitamin D deficiency?
The most common risk factors for developing a Vitamin D deficiency are obesity, living at or above a latitude of 35 degrees (we are at 47.78 in Bothell), aging, having darker skin (need more exposure to sun to get adequate Vitamin D because pigment acts as sunblock), decreased sun exposure (sunblock, cloud cover, avoidance of sun, pollution, ozone, season, time of day, etc. can all play a role in further decreasing UVB exposure).
How to I get tested for Vitamin D deficiency?
New guidelines for optimal Vitamin D levels have just been released. People without disease/illness should aim for a level between 40-70 ng/mL in the blood. People with illness present or who have risk factors for Vitamin D deficiency should aim for an optimal level between 55-70 ng/mL. A simple blood test for 25-hydroxy-Vitamin D is the best way to establish your current Vitamin D level. The cost of this test in my office is $39.00 plus blood draw fee. This level can tell us if you have a Vitamin D deficiency. Once we have established your Vitamin D level, it is important to work with a practitioner to determine how much Vitamin D you will need to take to treat your deficiency.
How Much is Too Much?
Even a couple of years back, we were told that Vitamin D toxicity could happen with dosages above 2,000 IU/day. Now we are finding toxicity in levels mostly above 50,000 IU/day over a prolonged period. Toxicity seems to occur more frequently with D2 (ergocalciferol) than D3 (cholecalciferol). Blood levels over 100ng/mL are considered excessive while levels at or above 150ng/mL are considered toxic. Symptoms of Vitamin D toxicity are: nausea, vomiting, pain in joints, abdominal cramps, diarrhea alternating with constipation, or hypercalcemia (increased calcium in the urine and blood). If toxicity is suspected or shown, discontinue any Vitamin D supplementation and avoid the sun.
Since deficiency is rampant in this region, getting tested is a good idea for everyone! Schedule your appointment for Vitamin D testing (and other services) today!