While on a recent trip I had the opportunity to read an article in the American Medical Athletic Association journal (Spring edition, 2014) written by Dr. Alan Roth, PhD. Dr. Roth refers to studies and papers written by Dr. John J. Cannell, MD who is described as a “frontier of vitamin D research and is the executive of the Vitamin D Council”. While this article pertains mainly to athletes, I believe it is adaptable to the average citizen as well. Dr. Roth states that “having read more than a thousand research reports on Vitamin D, I have observed that positive results for some diseases are not seen until the blood serum level of 25(OH)D reaches 70 ng/mL and higher”. He goes on further to state that in athletes, peak performance requires blood levels “approximately 50 ng/mL”.
Dr. Roth goes on to say “while 5,000 IU/day of D3 is widely recommended (and endorsed by the Vitamin D Council), athletes can take up to 10,000 IU/day without worrying about adverse effects”. Dr. Roth believes that in his review of the literature achieving toxicity is remarkably difficult and in his article he quotes Dr. Cannell who writes, “if there are any studies showing 20,000 IU/day is unsafe, I would like to see them.”
The one side effect of concern is hypercalcemia or elevated blood calcium levels. At doses “below 10,000 IU/day are not usually associated with toxicity, whereas doses equal to or above 50,000 IU/day for several weeks or months are frequently associated with toxic side effects”. However, those type of doses are rarely recommended to my knowledge.
The conclusion of Dr. Cannell is his suggestion of “an intake of 5,000 IU/day of D3 as the minimum for most adults with higher doses for those who need more to reach 50 ng/mL”.
The other issue is how much sunlight is needed to help with the metabolism and conversion of vitamin D. “It is recommended you receive about 15 minutes of exposure with minimum clothing to get 10,000 to 25,000 IU’s of D3″. The darker your skin and the season may make this time interval vary. In my opinion, checking your vitamin D level twice a year (such as January and June) will give you an idea of how the seasons and your skin tanning impact your own vitamin D level, assuming similar clothing and time in the sun with each season.
For the athlete, there is some evidence of improved strength, an increase if type II (fast-twitch) muscle fibers, and fewer injuries in the treated groups with vitamin D compared to controls.
My interest in patient management is the apparent association with better levels of vitamin D and the prevention of certain diseases. While this remains a “correlation” and is not certain to be a “causation” issue, none the less, it appears to be helpful in my mind to help reduces some allergic responses, heart disease and possibly cancer. In addition, it is my believe that, while controversial, there is a reduction of upper and lower respiratory infections such as sinusitis and bronchitis.
I can recall as a young man, my mother having me down a teaspoon of cod liver oil on the way out the door when going to grade school. It was her ardent belief that this ritual would help ward off the common cold. While being unpleasant, this was basically taking the purest form of vitamin D, and I now find myself recommending this action to many of my patients during the fall and winter. Especially for those family’s at higher risks of contracting a viral illness, such as mother or grandparent’s exposed to little ones, school teachers or day care center employees, flight attendants, just to name a few.
As always, chat with your doctor about their opinion and further information can be obtained in my office during your next visit if you are an established patient.