Is Vitamin D Supplementation Useless?

SWIMMING AND SUNNING ON THE BEACH AT ROCKY POI...
SWIMMING AND SUNNING ON THE BEACH AT ROCKY POINT PARK - NARA - 546942 (Photo credit: Wikipedia)

Dr.  Stephanie Senef, a MIT research scientist recently spoke out against Vitamin D supplementation at a Weston A Price Wise Traditions conference, saying that supplements are “a waste of money.”  I believe she is wrong about supplementation although correct about the sun being a superior source for those lucky enough to live in the right conditions.

Senef believes that the beneficial products of sun exposure occur before you manufacture Vitamin D.  When you expose your skin to sunshine, your skin synthesizes vitamin D3 sulfate. This form of vitamin D is water soluble, unlike oral oil-form vitamin D3 supplements, which are unsulfated. The water soluble pre-vitamin can travel freely in your blood stream, whereas the unsulfated supplement needs LDL ( so-called “bad” cholesterol) as a vehicle of transport. Dr. Seneff says:

 

“The sulfated form of vitamin D does not work for calcium transport, which I find very intriguing. And in fact, I think it’s the sulfated form for vitamin D that offers the protection from cancer. It strengthens your immune system. It protects you from cardiovascular disease. It’s good for your brain. It helps depression. I think all of those effects of vitamin D are effects of vitamin D sulfate.”

 There are several problems with this.  First, the research on Vitamin D status and cancer, cardiovascular disease, depression and other diseases was not performed only on people with sun-induced Vitamin D levels and it is likely that the relatively high levels of 25(OH)D in their blood would not come from sun alone unless they lived in climates south of the US  (and  most were done here.) For instance, in a recent study that I will describe below (video reference at end), pregnant women living in Charleston, SC where the sun shines strongly 325 days a year and the latitude favors the rays of sun that make Vitamin D, were overwhelmingly deficient or insufficient in their Vitamin D levels before supplementation.  Another study on lifeguards in Hawaii found that many had suboptimal blood levels. Between sunscreen or blocking mineral particles in  most skin products and cultural practices of showering frequently, we tend not to manufacture much Vitamin D.  So to get relatively high levels shown in the chart below and at this link,  It is likely that subjects used supplementation although only the resultant blood levels of 25(OH)D were canvassed.

vitamin D Deficiency Diseases by Blood Level

Note that only rickets is prevented with low blood levels of Vitamin D

(To enlarge, see  disease_incidence_prev_chart_101608)

In a recent study at the University of South Carolina medical school, expectant mothers, especially African American mothers, tested as insufficient to deficient in Vitamin D.  At the start of the study, deficient or insufficient levels of vitamin D were seen in 94% of the African-American women, 66% of Hispanic women, and 50% of white women who participated..  A select group was prescribed 4000 iu daily of Vitamin D3 in their second and third trimester and that group had 50% fewer adverse events such as to develop gestational diabetes, pregnancy-related high blood pressure, or preeclampsia than those taking 400 iu.  They also had fewer preterm births.  It benefited both the mother and baby and researcher Dr.  Carol Wagner felt that in the future higher amounts would test as even better, seeing no problem with 10,000 iu.  In a Norwegian study published in Epidemiology, pregnant women who took vitamin D supplements of 600-800 iu had 27 % lower rates of potentially fatal per-eclampsia.  Doesn’t sound like a waste of money to me!

Reinhold Veith studied research on Vitamin D from the sun and supplementation.  He  found that supplementation in adults below 10,000 iu daily had a pretty flat effect on 25HydroxyD (blood Vitamin D) levels but that higher levels brought D up to levels found by ultraviolet light from the sun or fixtures.  He did find that Vitamin D2 supplementation was less effective at raising blood levels of 25OHD than Vitamin D3, although some researchers dispute this.

I will be the first to say that supplementation alone is not the best way to get Vitamin D. According to researcher Michael Holick, this is difficult: to get it from the sun during late fall to early Spring, you must live south of Atlanta, go out without sunscreen between 11am and 1 pm and not wash it off for 3 days since bacteria on the surface of the skin synthesize it and can be washed off, even with plain water. If your skin is dark, you may need 6 times as much sunlight. How many people can do this?  Sunshine produces more than Vitamin D and Holick believes it is likely that breakdown products from UV and excess Vitamin D that are missing from supplements are useful to the body.  But that is a far cry from calling supplementation useless or a scam.

There are two forms of supplementation: oil and dry based Vitamin D3.  I prescribe dry Vitamin D to clients without gallbladders and the concentrated Biotech dry form to people who need to build up stores rapidly.  Neither form is sulfated, although we do not have evidence that they cannot become sulfated in the human body or in our flora.  Perhaps Dr. Senef’s theory indicates that dry Vitamin D supplements would be better than oil based forms.  However I see clinical results from oil based forms as well.  Cod Liver Oil, proposed by the Weston A. Price Foundation is an oil-based form of Vitamin D.

There is no good evidence that all of our vitamin D should come from Cod Liver oil, although I personally believe some of it should.  To get 10,000 iu via cod liver oil would incur toxic levels of Vitamin A.  Some Vitamin A is probably needed although there is conflicting research on it- given that research is unclear, I stand behind traditional practices.  Carlson’s cod liver oil is closest to the traditional A:D ratio in a commercial oil.   Fermented cod liver oil is possibly superior, but there is no real research and I was unable to get data from the manufacturer Blue Ice, even on the relative levels of Vitamins A and D.  I would have no hesitation to use it for my Omega 3 supplement, adding Vitamin D3 at levels of 10,000 iu, depending upon blood test results.

We have moved far from our equatorial origins and dress ourselves in clothing that usually covers all but 5% of our bodies. Most of us work indoors and are not suntanning at noon, and we shower frequently, washing away the skin bacteria that make the sulfated Vitamin D.  Most facial make-up and skin lotions provide a level of sun blockage even if direct sunscreens are not added.  While doctors used to think that such exposure was sufficient, that was based upon prevention of rickets, which as the chart show requires ridiculously little Vitamin D, and not the other conditions like cancer or heart disease that require higher blood levels.  We know that Vitamin D is a natural hormone necessary for  a broad variety of biological activities.  While getting what sun we can is important, we should not let the optimal be the enemy of the good.

 

Photograph of Cod Liver Oil capsules.
Photograph of Cod Liver Oil capsules. (Photo credit: Wikipedia)

 

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