For those of you who have read Grain Brain, you will recall that one of the fundamentally important nutritional supplements I recommend is Vitamin D3.
For years we have been schooled as to the importance of vitamin D in the process of building strong and healthy bones. Indeed, that part of the story is true. But the story becomes much more interesting as we recognize the expansive role of vitamin D in human health.
Vitamin D is actually not even a vitamin by definition. Vitamins are health-necessary chemicals not synthesized in the body which must be supplied from exogenous sources. So vitamin D, which the body readily synthesizes when it is exposed to sunlight, does not fulfill the definition of being a vitamin. In fact, vitamin D is a steroid hormone quite similar in structure to other hormones like estrogen, progesterone, and testosterone. This should be expected since all of these steroid hormones, including vitamin D, are all made from the same starting chemical, good old cholesterol. More on that later.
We now understand that vitamin D stimulates more than 900 genes in human physiology, most of which reside in the brain. These genes code for a variety of activities like reducing inflammation, strengthening nerve cells, and even helping the brain rid itself of viruses.
So it’s no wonder that there is a dramatically decreased incidence of a degenerative disease like Parkinson’s (67% lower risk) in people with the highest level of vitamin D.
This study was published in Archives of Neurology, a specialty journal published by our friends at the American Medical Association and it bears our attention.
People often ask me what I recommend as the appropriate dosage of vitamin D for an adult and my response is that there is no specific recommendation that works for all. You have to measure the blood level of vitamin D and adjust the dosage to optimize the level. With my patients I target a level of around 79-80 nanograms per milliliter. This may require 5000 IU daily, more, or even less.
One final note. We frequently find dramatically low levels of vitamin D in individuals who are gluten sensitive, often along with very low levels of vitamin B12. Now that you know that vitamin D is made from cholesterol, the association of lower vitamin D status with the use of statin cholesterol lowering medications makes sense.