Vitamin D Controversy Continues

It is now generally accepted that Vitamin D plays a far larger role in maintaining health than simply helping to produce higher quality bone. Vitamin D has shown itself to be an important player in immunity, prevention of certain types of cancer, management of diabetes, and, most recently, prevention of heart disease.

However, there is still some uncertainty about the dosage, sources, and toxicity of this nutrient. This article offers a nice summary of Vitamin D. There are several points in the article with which I agree, but I feel that some clarification may be useful.

TESTING
We now have at our disposal a reliable, consistent blood test that can evaluate a patient's Vitamin D status. As this test became more popular, it was quickly discovered that most of us walk around with alarmingly low levels of usable Vitamin D (referred to as "D3"). With that, much of the fear of Vitamin D toxicity has fallen by the wayside. Most laboratories have an reference range of 30-100 ng/mL, but I feel that the "Optimal Range" is 50-80 ng/mL. As stated in the article, even with aggressive therapy, values on this test are slow to change. I often will not repeat test for 6 months. The experts state that Vitamin D becomes toxic at 150 ng/mL, which would take heavy dosing over a long period of time to achieve.

DOSAGE
Dosages of Vitamin D supplements are usually measured in International Units (IU). Most commonly, I will recommend 5000 IU to 10000 IU per day. A much more common way of representing dosages is milligrams (mg). So, what are these dosages in milligrams? 0.125 mg to 0.250 mg--or 125 to 250 micrograms. That is not to say that exorbitant dosages are not dangerous, but there is a huge difference between "10000 IU" and "0.250 milligrams" in the mind's eye.

Some sources state that 30 minutes of sun exposure with 40% skin exposure (for example, shorts and short sleeves) per day will allow your body to produce 10000 IU of Vitamin D. It has been stated that the average daily loss of Vitamin D through normal metabolism is between 3000-5000 IU. Therefore, if blood tests have shown Vitamin D deficiency, you will not likely gain ground by taking the currently-recommended 2000 IU per day, especially in the winter.

GET TESTED!
The only way to get a sense of your Vitamin D status is to get the blood test performed and follow up accordingly. If there is a personal or family history of cancer, heart disease, depression, immune system problems, chronic pain, or autoimmune disease, Vitamin D deficiency may play a role.