Saturday, November 15, 2008

Spliced feed for The Science Network

Spliced feed for The Science Network

Vitamin D Dilemma - To D or Not To D [Sciencebase Science Blog]

Posted: 14 Nov 2008 07:00 AM CST

Radiological health expert Daniel Hayes who works at the New York City Department of Health and Mental Hygiene recent published on the subject of low dose radiation and the possibility that a form of vitamin D could be the key to protecting us from background radiation and perhaps save lives following a nuclear incident or terrorist attack involving a so-called dirty bomb.

Hayes explains that calcitriol, the active form of vitamin D, could be the oral agent, that medics have been searching for to provide a quick, simple, and inexpensive way to protect us when the warning sirens sound.

Having spoken to various researchers with markedly different views on vitamin D, its benefits and its its potentially detrimental effects on health, I wasn’t too sure about how adding yet another dietary supplement to our daily intake would be beneficial. I asked Hayes to expand.

“One should get vitamin D3 either from solar irradiation of the skin or from dietary supplementation,” he told me, “I personally take 2000 IU daily which is obtained without a physician’s prescription…2000 IU is definitely safe, I can dig up the documentation.”

There are claims from some quarters that getting plenty of sun is a good thing, and they’ve published a guide, which I mentioned in a post on how to sunbathe safely, but the cancer research charities suggest that really there is no safe way to get a sun tan and that a dietary supplement of vitamin D would be a much safer alternative to increasing one’s exposure to the sun.

However, the only prescription vitamin D preparation available in the US and the US is vitamin D2 (ergocalciferol). “Vitamin D2 should not be regarded as a nutrient suitable for supplementation or fortification,” Hayes says, “physicians resorting to the use of vitamin D2 should be aware of its markedly lower potency and shorter duration of action relative to vitamin D3.” As such, he asserts that you should get vitamin D3 either from the sun or through dietary supplementation.

Unfortunately, vitamin D, being several different compounds with different physiological activities, is not a clearcut medical case. There are some who see it as a “clap-hands-hosanna”, but there are others, particularly scientists associated with the Marshall Protocol, and in the California non-profit association Autoimmunity Research Foundation, who see it as something to be avoided.

Biomedical researcher Trevor Marshall, who runs the ARF, has produced what has been described as the first working model of vitamin D metabolism. Proal explains that the model, which demonstrates the complexity of vitamin D metabolism, emphasizes the importance of distinguishing between the different forms of vitamin D. According to ARF scientists, the form of vitamin D that Hayes recommends and takes himself - that derived from supplements and excessive sun exposure - is apparently converted into 25-hydroxyvitamin-D or calcidiol. “Unfortunately,” says Proal, “molecular biologists have long realized that 25-hydroxyvitamin-D3 is actually a potent secosteroid. Marshall’s research indicates that, like corticosteroid medications, it actually slows the immune response, and this ultimately allows chronic bacterial infection to exist uninhibited, which could be the ultimate cause of such inflammation. “Under such circumstances,” says Proal, “25-hydroxyvitamin D’s ability to slow the immune response allows for short-term relief, but aggravates the disease over the long-term by allowing chronic pathogens to proliferate with much greater ease.”

The difference
cacitriol and
calcidiol boils down
to the
manner in which
they bind the Vitamin
D Receptor VDR
The difference between cacitriol and calcidiol boils down to the manner in which they bind the Vitamin D Receptor VDR - a receptor that largely controls the activity of the innate immune response and the transcription of hundreds, and possibly thousands of genes. While calcitriol activates the VDR, Marshall’s in silico data demonstrates that calcidiol has the opposite effect. So according to ARF researchers, Hayes may be right about about calcitriol’s ability to activate genes that allow for protection against radiation. But, taking vitamin D orally or basking in the sun will produce a form of vitamin D that has the exact opposite effect of the beneficial results that Hayes predicts.

Reporting for, Stephen Strauss explains how Marshall researchers looked at more than 1000 people with a host of autoimmune and related diseases. “When combined with a particular drug treatment program, people who consciously tried not to take vitamin D and stayed out of the sun showed an often-dramatic reduction in symptoms. Dramatic means a reduction of 81 per cent in symptoms for people suffering from conditions ranging from Type 2 diabetes, to rheumatoid arthritis, to multiple sclerosis, Lyme disease and Crohn’s disease.”

It seems that some forms of vitamin D have steroidal activity and rather than helping fight disease it modulates the immune system and potentially increases inflammation. Marshall explained the apparent paradox in the journal BioEssays:

“For half a century, medical science has been noting the association between vitamin D serum levels and disease. What developed has been a concept of ‘vitamin D deficiency’ based solely on the notion that ‘low’ vitamin D serum levels somehow cause disease processes. But this ignores the alternative hypothesis — that the disease processes themselves regulate the vitamin D metabolism —that the observed ‘low’ values of vitamin D in disease are a result of the disease process, not the cause.”

I asked Amy Proal, a medical researcher and an advocate of the Marshall Protocol, for her thoughts on vitamin D. “Who is getting better as the medical community dishes out more and more vitamin D,” she asked in response. She points to a report in The New York Times that says children as young as five years are developing kidney stones and that infant eczema is rising at an alarming rate, these trends and the trend towards obesity, she says are not what one would se with genetic or autoimmune diseases. “They are trends that indicate chronic infection egged on by the use of immmunosuppressive steroids, and vitamin D fortification, among other trends of modern medicine,” she says. The NYT article alludes to the recent melamine in milk scandal in China, but stakes its claim on common salt (sodium chloride) being to blame for the rise in kidney stone incidence in the US.

So, is vitamin D good or bad? Either way, which forms should we allow ourselves to be exposed to and which forms should we really avoid? And, if there’s a radiation incident…

Daniel P. Hayes (2008). The protection afforded by vitamin D against low radiation damage International Journal of Low Radiation, 5 (4) DOI: 10.1504/IJLR.2008.020980

Vitamin D Dilemma - To D or Not To D

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