Brennan makes a very good point. I have often heard people say “It’s a water soluble vitamin so I dont have to worry about toxicity” which isnt true. All vitamins are drugs and need to be treated as such. Nearly every prescription drug is water soluble and many of them are excreted through the kidneys yet they all have potential side effects especially if the patient takes more than the prescribed dose, so water solubility does not protect one from side effects or from the risk of overdosing whether its a prescription drug or an OTC drug like vitamin supplements.
I’m glad to see that we all agree that dosing is important with vitamins and as Brennan and I have pointed out numerous times, the average American seems to get adequate amounts of these substances. The doses in these studies may be much higher than the RDA but they are right in line with the amounts found in the most common supplements that people take. In fact I find that many of my patients are taking 2,000iu of vitamin C in the winter time. By that measure it was a fair study if you are trying to determine the affect of commonly available supplements on the body.
Makes sense to me. If people already intake their RDA through a regular diet, they need to bump up the dosage to detect the effect of, well, additional dosage. Unless the 90 mg of vitamin C is meant as an additional intake on top of what we already get from our diet, which wouldn’t really make sense. They needed to decide on a number, so they picked 1,000 mg. They had to pick something, right? And if many of macgyver’s patients take 2,000 mg, the 1,000 mg they decided to go with sounds reasonable to me.
I think this might fit in here. Claims about vitamin D3 seem to have reached faddish proportions. Several of my friends (remember I live in La-La Land) who are not skeptical and who don’t investigate such things, are now swearing by it. I can’t find anything on the Internet that explains the difference between Vitamin D3 and any other kind of vitamin D supplement. I’m hoping that McGyver might weigh in.
What is Vitamin D3? How does it differ from other kinds of Vitamin D? Is it superior in any way? Nobody seems to be explaining it.
These friends also claim that their doctors (not sure what kind of doctors) have checked the D levels in their blood and found them “very low” so they keep raising the dose. But I have heard that these blood tests are unreliable. Among people who live in Southern California who go outside during the day, I doubt that anyone here suffers from any kind of Vitamin D deficiency. I also understand that there is a new book by a “nutritionist” touting the magical qualities of Vitamin D3.
What’s the story?
Lois
One of the problems with living in la-la land occurs when one’s ancestors are from northern Europe and have essentially zero protective pigmentation. I got tired of having my dermatologist zap incipient skin cancers so I slather myself with infinity SPF cream when I go out in the sun. Probably less UV gets to my skin than it does for George up in Canada. (So just don’t tell Macgyver or McKenzie that I take a vitamin D capsule each day).
Occam
I think this might fit in here. Claims about vitamin D3 seem to have reached faddish proportions. Several of my friends (remember I live in La-La Land) who are not skeptical and who don't investigate such things, are now swearing by it. I can't find anything on the Internet that explains the difference between Vitamin D3 and any other kind of vitamin D supplement. I'm hoping that McGyver might weigh in. What is Vitamin D3? How does it differ from other kinds of Vitamin D? Is it superior in any way? Nobody seems to be explaining it. These friends also claim that their doctors (not sure what kind of doctors) have checked the D levels in their blood and found them "very low" so they keep raising the dose. But I have heard that these blood tests are unreliable. Among people who live in Southern California who go outside during the day, I doubt that anyone here suffers from any kind of Vitamin D deficiency. I also understand that there is a new book by a "nutritionist" touting the magical qualities of Vitamin D3. What's the story? LoisThis is a real pet peeve of mine. You are correct. Vit D has become the Vit B12 of the 21st century and its no just in La La Land. in the last century doctors often gave fatigued patients Vit B12 as the cure all for fatigue and many other ailments. We are a little more sophisticated today and no we know that B12 does nothing for a patient unless they have a documented B12 deficiency. Apparently we are not as sophisticated as I thought though. We have simply substituted one unscientific practice for another First a little background: Vitamin D is not truly a vitamin since humans are capable of producing it on their own. Vit D3 is the active molecule of Vit D and it is formed in the skin when exposed to UV rays. Vit D is a fat soluble vitamin which means the body is unable to get rid of extra Vit D if a someone takes too much. In large amounts it can be toxic to the liver. When measuring Vit D levels in the blood the recommended form to measure is 25 OH Vit D but because Vit D is fat soluble the amount found in solution in the water based serum is not always in equilibrium with the Vit D stored in the tissues. When this fad began and everyone came in asking for Vit D levels I relented and drew levels on the first 50 patients as a study of my own. It was done between June and August and out of 50 patients only one had "normal" levels. These were all perfectly healthy people. I quickly came to the conclusion that there was something very wrong with the way we were measuring and interpreting these tests. Fatigue is one of the most common complaints that patients bring up to their doctors. Its also one of the hardest to treat since the vast majority of cases are do to life's daily stress rather than any real medical issue. Patients don;t want to hear that though. They want to be told their is a real problem that can be cured with a pill. In the past decade or so a number of population based retrospective studies have been done that showed a correlation between vitamin D intake and lower rates of cardiovascular disease and some cancers. Other studies also showed that a very large proportion of the population have levels of Vit D which are below the "normal" range. What should have happened at this point was that the medical and science communities would begin RCT's to see which if any of these benefits were actually cause and effect and which were just correlations. Unfortunately we live in a world where the media is always craving the latest medical news and consumerism has entered the medical field so that doctors feel compelled to give patients what they want and also to appear that they are always on the cutting edge. As a result no one waited for the real studies to come out. Vit D quickly became the cure all for almost everything. What do the real studies show? So far the small number of RCT's that have been done have shown no benefits from Vit d supplementation for any of the conditions studied. There are absolutely no studies that demonstrate that measuring Vit D levels and supplementing them is either safe or beneficial for anything except a few conditions like rickets. So where are we now? Across the country many doctors are measuring vitamin D levels and supplementing everyone who's level is low despite a complete lack of evidence to support this practice. Patients love it though and many swear by it because the placebo effect is very strong especially in people who have vague subjective symptoms and especially if they continually read about the benefits of this treatment and see it on all the news programs and talk shows. In my personal opinion this is all a fad created by preliminary studies, an overzealous and medically ignorant media, and physicians who feel an increasing need to compete in medical environment where consumerism is unfortunately influencing how physicians practice. I'm not saying Vit D levels and supplementation is a bad thing. What I am saying is that no one knows. The doctors who are following this practice are practicing bad medicine and the patients who are caught up in this fad may find out 10 or 20 years from now that it was a waste of time and money or worse, they may find out there were harmful effects associated with this practice. Instead of jumping on the latest fad everyone should just take a step back and wait for the RCT's even if it takes a decade or more. Regarding Occams comment, The RDA for Vit D is 800-1,000 iu daily so if you are taking a supplement that is in that dosage range I have no evidence to say its harmful to do especially if you do not eat a lot of fish or other items high in Vit D. I would strongly advise against having your Vit D level checked though and certainly would avoid the 50,000iu doses I have seen some doctors giving their patients.
Thanks for your response on Vitamin D. Macgyver (one of these days I will get the Mcs and the Macs right).
I have heard that sunscreens generally don’t interfere very much with Vitamin D production and that most people don’t apply enough, anyway, not even the recommended amount, which means they are not only not lessening the Vitamin D production substantially, but they aren’t protecting themselves from cancer-causing rays as much as they think, either.
Here’s an article that appeared in The British paper, the Daily Mail. It says how much sunscreen is required for protection and also says sunscreen doesn’t lessen Vitamin D production all that much. Occam might be interested in seeing if he is using enough.
I would have liked to give a link to a scientific paper, rather than a newspaper, but I was unable to find one. Most of the newspaper articles i’ve found seem to say (definitely) maybe yes, maybe no to both skin cancer protection and the lessening of Vitamin D production, though IMO, it is probably offering some skin cancer protection.
I’d still like to know what Vitamin D3 is.
Lois
I'd still like to know what Vitamin D3 is. LoisI did answer this above but my post was pretty long so I can see how you could have missed it. Vit D3 is the active form of Vit D. There are a number of biochemical reactions required to produce Vit D but the step in which 7-dehydrocholesterol is converted to Vit D3 is the one that requires UV rays and occurs in the skin. Further modifications of the molecule then occur in the liver and he kidneys as illustrated below. There are two forms of Vit D that are sold as supplements. Vit D2 and Vit D3. D2 comes general from fungal sources like mushrooms and D3 comes from animal sources. There are claims that D2 is not as bioavailable as D3 although I can not find any evidence to suggest this is clinically significant. That never stops manufacturers from making unsubstantiated or exaggerated claims though.
Thanks, MacGyver. That’s helpful. Best to you.
Lois
I also understand that there is a new book by a "nutritionist" touting the magical qualities of Vitamin D3. LoisFirst of all, anyone can call themselves a 'nutritionist', it is a label without meaning. If you want to talk to someone who knows what they are talking about regarding nutrition, you have to talk to a Registered Dietitian. RD is a licensed title guaranteeing this person has training in what they are touting. Impersonating an RD can get you into trouble, the 'nutritionist' label means absolutely nothing. My 10 month old granddaughter can call herself a nutritionist.
I use the SPF 50 (Rite-Aide for infants), as well as avoiding the sun when I can, Lois.
Congratulations on your granddaughter, Asanta. OK to hire her for dietary recommendations? :lol:
Occam
I use the SPF 50 (Rite-Aide for infants), as well as avoiding the sun when I can, Lois. Congratulations on your granddaughter, Asanta. OK to hire her for dietary recommendations? :lol: OccamHer recommendations would be as good or better than those of any nutritionist. %-P Lois
The book I mentioned is this. The author, Dr, Marc Sorenson, does not describe himself as a nutritionist, but uses the title Dr. However his doctorate is in Education. He and his wife, both Mormons, own and operate a health resort. He received his Ph.D from Brigham Young University.
Information about the book: Mercola Market - Shop Products Recommended by Dr. Joseph Mercola
Information about Sorenson is available on Wikipedia.
Lois
The book I mentioned is this. The author, Dr, Marc Sorenson, does not describe himself as a nutritionist, but uses the title Dr. However his doctorate is in Education. He and his wife, both Mormons, own and operate a health resort. He received his Ph.D from Brigham Young University. Information about the book: http://products.mercola.com/vitamin-d3-book/ Information about Sorenson is available on Wikipedia. LoisYes, and I'm an engineer because I have a degree in nursing. I have a bridge (I built) to sell you. What a quack.
while this is by no means a universal truth, by and large the doctors who write books are generally quacks or at least they are vastly over represented among the authors of books written for the public on medical issues. I often find myself having discussion with patients who are following some new diet or asking for some unnecessary test because one of these doctors wrote about it and when I explain to the patient why the particular idea is incorrect they will often say “But he/she wrote a book” because the general public thinks that if you wrote a book and got it published you must be a respected doctor who knows what they are talking about. IN reality what it often (although not always) means is you are a deluded or egotistical individual who is just looking for fame and fortune and the best way to get there is to write a book that makes exceptional but scientifically flawed claims.
while this is by no means a universal truth, by and large the doctors who write books are generally quacks or at least they are vastly over represented among the authors of books written for the public on medical issues. I often find myself having discussion with patients who are following some new diet or asking for some unnecessary test because one of these doctors wrote about it and when I explain to the patient why the particular idea is incorrect they will often say "But he/she wrote a book" because the general public thinks that if you wrote a book and got it published you must be a respected doctor who knows what they are talking about. IN reality what it often (although not always) means is you are a deluded or egotistical individual who is just looking for fame and fortune and the best way to get there is to write a book that makes exceptional but scientifically flawed claims.Yes, most doctors writing these books are far outside of their fields of expertise and training, and should not be given any more credibility than if your John Doe next door neighbor did the same. Not all doctors are researchers. Off the top of my head, Dr Paul Offit is an exception that comes immediately to mind. He is a scientist/researcher and his books about vaccination are well within his field of research expertise. Why anyone would listen instead to a nosepicking playboy model is beyond comprehension.
The thread, Fighting Unreason in the Pseudoscience thread addresses another facet of this problem. Those doctors could be included along with the physical science.
Occam
Latest review of reviews for Vitamin D:
Evropi Theodoratou, Ioanna Tzoulaki,Lina Zgaga, John P A Ioannidis. Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational studies and randomised trials. BMJ 2014;348:g2035 Abstract Objective To evaluate the breadth, validity, and presence of biases of the associations of vitamin D with diverse outcomes. Design Umbrella review of the evidence across systematic reviews and meta-analyses of observational studies of plasma 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D concentrations and randomised controlled trials of vitamin D supplementation. Data sources Medline, Embase, and screening of citations and references. Eligibility criteria Three types of studies were eligible for the umbrella review: systematic reviews and meta-analyses that examined observational associations between circulating vitamin D concentrations and any clinical outcome; and meta-analyses of randomised controlled trials assessing supplementation with vitamin D or active compounds (both established and newer compounds of vitamin D). Results 107 systematic literature reviews and 74 meta-analyses of observational studies of plasma vitamin D concentrations and 87 meta-analyses of randomised controlled trials of vitamin D supplementation were identified. The relation between vitamin D and 137 outcomes has been explored, covering a wide range of skeletal, malignant, cardiovascular, autoimmune, infectious, metabolic, and other diseases. Ten outcomes were examined by both meta-analyses of observational studies and meta-analyses of randomised controlled trials, but the direction of the effect and level of statistical significance was concordant only for birth weight (maternal vitamin D status or supplementation). On the basis of the available evidence, an association between vitamin D concentrations and birth weight, dental caries in children, maternal vitamin D concentrations at term, and parathyroid hormone concentrations in patients with chronic kidney disease requiring dialysis is probable, but further studies and better designed trials are needed to draw firmer conclusions. In contrast to previous reports, evidence does not support the argument that vitamin D only supplementation increases bone mineral density or reduces the risk of fractures or falls in older people. Conclusions Despite a few hundred systematic reviews and meta-analyses, highly convincing evidence of a clear role of vitamin D does not exist for any outcome, but associations with a selection of outcomes are probable.
I fight this battle every day Brennan, not only with my patients but with colleagues. To listen to the media and even many corners of the medical community one would think its a a well established principal that we should measure vit D levels and supplement them to the normal range with the expectation that we may reap all manner of beneficial effects.
The fact is that some associations have been demonstrated but no causal links have been established between vit D supplementation and reduced illness. Furthermore it has not been shown that measuring vit D levels and then supplementing patients until their level is within the “normal range” is either safe or beneficial in the short range or the long term where some vitamins have been shown to increase cancer risks.
The media and my colleagues need to put the brakes on this fad until we know more.
So until we know more it could be possible that we don’t need Vitamin D at all?
Hmmn, interesting!
So until we know more it could be possible that we don't need Vitamin D at all? Hmmn, interesting!Not to go round and round again but that's not really what we're saying. What we're saying is that we don't know if taking additional amounts above what is in our diet is either safe or beneficial based on the existing evidence. As with all drugs, if there is no clear safety and efficacy data they probably shouldn't be used until we know more.