Hell-Jee,
I'm not a physician or nutritionist... but I did stay at a Howard Johnson a few years back...
Seriously... all I can do is provide you information based on my experience with, and what I've learned over the last three years about vitamin D3, Omega-3 Fish Oil and the rest of the vitamin D3 cofactors: calcium, magnesium, zinc, boron, vitamin A (retinol) and vitamin K2 (MK-4 & MK-7). Armed with this information, you can make your own decisions.
For starters, you've likely already discovered that most PCPs and too many neurologists have no real first-hand clinical experience treating patients with cluster headaches... That should be understandable... We suffer from an orphan disorder... When patients present with a condition they've not treated previously... like cluster headache, most physicians use a cookbook approach with treatment recommendations from Standards of Care Guidlines... Many of these guidelines are excellent... That said, it all depends on when the cookbook (Guideline) was published...
Unfortunately, the same can be said for the benefits of nutrition and the use of supplements on the many health issues we face...
This shouldn't be surprising either... Most medical school curricula provide an average of 1 hour on primary headaches and about the same amount of time on the use of nutrition as a mode of preventative and interventional treatments.
Furthermore, most of the exciting medical breakthrough discoveries in the last ten years have come as a result of molecular biochemistry at the cellular and nuclear level... in short, rise of the genetic-based pharmaceutical companies...
To put this in perspective, the Human Genome Project wasn't declared substantially complete until April 2003 with sequencing of the last remaining chromasome not completed until May of 2006.
Getting back to the pharmacokinetics of vitamin D3, the real exciting stuff has come as a result of gold standard RCTs completed in the last five years and the use of vitamin D3 as a preventative for cluster headache didn't start until three years ago when I developed the basic anti-inflammatory regimen.
Moreover, until now, the only first hand information on the efficacy of vitamin D3 as a preventative for cluster headache has only been available here at CH.com. Other sites like ClusterBusters and a couple cluster headache organizations in Europe have been watching.
Sooo... unless physicians have been taking CME specific to vitamin D3 and nutrition... they've likely never been exposed to the health benefits of vitamin D3 and the vitamin D3 cofactors.
With that as a preface... here's what I suggest. VitaminDWiki provides the most complete and up to date compendium of all things vitamin D3 including excerpts, and links to the latest RCTs...
For example, here's the link to the benefits of taking vitamin D3 to control cholesterol:
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The really cool thing about vitamin D3, 25(OH)D and 1,25(OH)2D3, (calcitriol), the active hormonal form of vitamin D3 is its capacity to stimulate genetic expression...
In simple terms calcitriol triggers certain genes to produce products our bodies need to heal themselves and turn off genes to prevent them from making products that make us sick.
It's this capacity of vitamin D3 we think is responsible for the down-regulation/suppression of Calcitonin Gene-Related Peptide (CGRP) that studies have found elevated during cluster and migraine headaches. Dr. Peter Goadsby, M.D., one of the world's top cluster headache neurologists, conducted one of these studies.
In order to help make genetic expression happen, we need to supplement with adequate amounts of vitamin D3, calcium, magnesium, zinc, boron, vitamin A (retinol) and vitamin K2 (MK-4 & MK-7). The following graphic provides a high level illustration of how this happens...
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You can find more about the synergy between vitamin D3, vitamin A and vitamin K2 at the following link:
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The founder of VitaminDWiki has been kind enough to post a web page on the use of vitamin D3 as a cluster headache preventative at the following link:
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Proof Vitamin D Works - A list of links to RCTs studying the use of vitamin D3 to treat and prevent a long list of health problems:
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Finally, no discussion of vitamin D3 therapy is complete without discussing safety. The following graphic tells the tale on safety of the doses we take. Note that it's not just the dose but also the duration of dose that adds up...
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This graphic doesn't tell the whole story... It's not so much the dose and duration but rather how much 25(OH)D the body produces in response to these doses over time.
Even that can be misleading as it's not the serum concentration of 25(OH)D that indicates toxicity... It's the serum concentration of calcium...
If you read through the papers on vitamin D3 toxicity you'll find there are no studies (RCT's) that intentionally set out to define the vitamin D3 dose and serum level of 25(OH)D that triggers a toxic reaction... That would be unethical...
Instead, they gathered data from cases of unintentional and accidental overdoses due to mislabeled or improperly prepared vitamin D3 that resulted in calcium serum concentrations above the normal reference range. These cases were then used to approximate vitamin D3 dosing and 25(OH)D thresholds where a toxic reaction occurred as indicated by too much serum calcium and or too much calcium in the urine.
In nearly every case, authors reporting toxic levels build in a large safety margin... For example, if the lowest threshold for vitamin D3 toxicity from any study (with or without peer review), was found to be 200 ng/mL, the "Safe" upper limit of the normal reference range is set at 100 ng/mL.
In short, the vitamin D3 experts, endocrinologists specializing in treating vitamin D3 deficient patients will say... vitamin D3 toxicity is very rare...
Finally, I've tried to put this on an apples to apples comparison of relative risk... I was unaware of any deaths reported to the FDA over the last 9 years due to vitamin D3... so I checked a web site that tracks reports like this... I think you'll find the following list an eye-opener...
From Q1 2004 to Q3 2012, (9 years), the FDA received adverse reaction reports on the following prescription medications and over the counter supplements: Check out the following link to see for yourself. Plug in prescribed and over-the-counter medications and supplements you’ve been taking… one at a time, to see what’s been reported to the FDA about these medications over the last 9 years. Click on the “Show More” button to see the entire list of adverse reaction reports for each choice.
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So there you have it... The next time a nervous Nellie cries "Wolf" in a post about taking vitamin D3... at the doses we take in the anti-inflammatory regimen... take a deep breath and remember the sage sayings... Too much of anything isn't good... and... All things in moderation...
Good people of Clusterville... Our healthcare system is going down the dumper at a frightening pace... The smart thing to do now is stay healthy. The anti-inflammatory regimen is a very safe regimen with health benefits that go well beyond preventing cluster headaches.
And if you do get sick and need to see a doctor... be informed... Ask for an explanation of any prescribed medication including side effects.
Take care,
V/R, Batch