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Medical Whats a Vitamin D Deficiency?

  1. Feb 11, 2009 #1
    this is long, but appears excellent

    Whats a Vitamin D Deficiency?


  2. jcsd
  3. Feb 11, 2009 #2

    jim mcnamara

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    Rickets is a childhood vitamin D deficiency disease, for example. The USDA recommends 200IU of vitamin D per day.

    If you drink whole milk in the US you probably get enough vitamin D right there. Exposure to sunlight makes vitamin D in your skin as well. Chances are good you are not deficient.

    Vitmain D has developed a certain cachet amongst the pill peddlers. There have been some journal articles reporting on vitamin D and DNA integrity checking, hence linking it to cancer prevention among other things . It is easy to develop hypervitaminosis D by taking too many vitamin D pills. Don't overdo it.

    This is a link to a newspaper article about DNA repair and Vitamin D. Articles like this triggered an avalanche of interest in Vitamin D. And helped pill peddlers and vitamin D test kit suppliers. :)

  4. Feb 11, 2009 #3
    i'm not sure how it helps "pill peddlers". vitamin D is one of the cheapest supplements on the market. many people really do not get much vitamin D, especially in the winter when the days are shorter. if you have an office job, and work in a cubicle, you may go the whole day without any exposure to sunlight. and if you're a dark-skinned person that lives in a higher latitude than your ancestors were adapted to, that compounds the problem. this may also mean you are lactose intolerant and not well-adapted to drinking milk.

    i would ask that you at least give it a look. it addresses some of your misconceptions such as the risk of hypervitaminosis.
  5. Feb 11, 2009 #4


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    Jim McN, I beg to differ. There is considerable new (last 15 years or so) research in the biomedical literature suggesting that the current FDA recommendation of 400 IU's per day is woefully inadequate. The FDA itself is looking into this, but don't expect anything soon since the wheels of government take years to turn.

    Because of prevalent sunscreen use due to legitimate concerns over skin aging and skin cancer, a large number of Americans are Vitamin D deficient even during the summer. (SPF 8 is sufficient to turn off V-D production in the skin). Many doctors are now recommending V-D supplements. There is an alternative movement by some people to instead get "natural" V-D through 5-10 minutes of daytime sun on the back or chest each non-winter day. That is being fiercely opposed by dermatologists and oncologists, who argue that supplements are far safer than regular sun exposure. The effects of sun exposure weren't a problem for our ancestors who died young, but cancer is an issue now that we live 80 years or more. Skin cancer prevention can lead to VD deficiency.
  6. Feb 17, 2009 #5

    jim mcnamara

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    Vitamin D suggested levels may not be 'woefully inadequate'.

    Yes, I saw lots of newspaper articles and the Canadian Cancer Society's suggestion of 100IU per day in the Winter months. This applies for people in boreal climes with short winter days and low angle solar incidence.

    Also saw some in vitro studies outlining Vitamin D's role as a prohormone and some of its interesting intracellular activities.

    From Pubmed:
    The cancer thing vs Vitamin D:
    Finds no correlation between serum "vitamin D"(my words) levels and cancer incidence
    in a large population study.

    based on: http://ods.od.nih.gov/factsheets/vitamind.asp
    Code (Text):

    Table 1: Serum 25-Hydroxyvitamin D [25(OH)D] Concentrations and Health
    *ng/mL** nmol/L**      Health status
    -------  --------- -------------------------------------------------------------
    <11          <27.5  Associated with vitamin D deficiency and rickets in infants and young children [5].

    <10-15    <25-37.5 Generally considered inadequate for bone and overall health in  healthy individuals [5,13].

     =30          =75  Proposed by some as desirable for overall health and disease prevention,
                       although a recent government-sponsored expert panel concluded that insufficient data are
                       available to support these higher levels [13,14].

    Consistently >200  Consistently >500 Considered potentially toxic, leading to hypercalcemia and
                       hyperphosphatemia, although human data are limited. In an animal model,
                       concentrations =400 ng/mL (=1,000 nmol/L) demonstrated no toxicity [15,16].

    Institute of Medicine, Food and Nutrition Board.
    Dietary Reference Intakes: Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington, DC:
    National Academy Press, 1997.

    Scientific Advisory Committee on Nutrition.
    Update on Vitamin D. Position Statement by the Scientific Advisory Committee
    on Nutrition. London: The Stationery Office, Limited, 2007.

    Holick MF. Vitamin D. In: Shils ME, Shike M, Ross AC, Caballero B, Cousins RJ, eds.
    Modern Nutrition in Health and Disease, 10th ed.
    Philadelphia: Lippincott Williams & Wilkins, 2006.
    Jones G. The pharmacokinetics of vitamin D toxicity.
    Am J Clin Nutr. In press
    Shepard RM, DeLuca HF. Plasma concentrations of vitamin D3 and its metabolites in the
    rat as influenced by vitamin D3 or 245-hydroxyvitamin D3 intakes.
    Arch Biochem Biophys 1980;202:43-53.
    The point of this time-comsuming paste and edit: A peer review of your 'woefully inadequate' statement as brought up by others, based on 'lots' of papers. They did not see a need to change things.

    This is from NIH - a Vitamin D factsheet.

    Care to rebutt? Please use NIH/pubmed citations so we are on a level playing field here.

    And I don't do this kind of post-it rebuttal very often because it takes way too long. And the result is not worth the effort most of the time.
  7. Feb 18, 2009 #6
    why ignore colorectal cancer? inverse means that less vit. D -> more colorectal cancer

    and why limit discussion to cancer, when there are so many ways to die?

  8. Feb 18, 2009 #7
    Agree with Tim - it's hype.
    Proton - it's a bit dishonest to offer the innocent question in order to suck in a response so you can rave at your pet subject.
  9. Feb 18, 2009 #8
    Jorge, I posted a presentation by an MD supplied by the University of California. it's hardly sucking anyone in.
  10. Feb 18, 2009 #9

    jim mcnamara

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    Proton Soup - there is an MD on cable TV - a baryatric surgeon (stomach stapling) -
    who developed and markets 'Full Bars'. Whatever those are. I'm not labelling MD's as bad folks, they just can be more businessmen than scientists. Ask Moonbear if you don't believe me. MD's can actually be mediocre scientists. Believe it or not.

    Just because someody has an MD or a PhD and then says something in a seminar or in a meeting or on TV does that make it scientifically accepted fact.

    Peer reviewed journals are much closer to that. And that is whole point of why I posted that stuff above. I can find hundreds of blogs and pill sites that "cite" scientific research on Vitamin D. If NIH is not convinced, then you convince them with high quality research.

    Right now the idea of tripling suggested Vitamin D daily requirements is on the fringe. That does not make it wrong, just not proven. It has to be proven to the point where most of the folks in Clinical Nutrition, and so on, are fully convinced.


    Changing daily dietary requirements has BIG impacts on things like school lunch menus, food labels, etc. A vitmain D change will probably also impact commercial dairies. I dunno. But the whole deal is not just 20 in vitro papers, and a few inconclusive population studies. It has far-ranging effects - so what is behind your proposed change has to be a concrete wall of science.

    There is no such wall now. Sorry.

    It is also hard to reverse these "requirements" things. About 10 years ago there was a push based on research to lower the Selenium daily requirements. It did not happen. So what happens if we jack up Vitamin D requirements and liver cancer at age 55 goes through the roof?

    If it worries you personally take pills or cod liver oil. Make your kids and wife do the same. Good luck on the wife part :)
  11. Feb 18, 2009 #10
    i'm all for peer-reviewed studies, actually. i just thought you were cherrying picking above when you cited that one for no effect on total cancer morbidity, yet it does have a positive effect on colon cancer.

    i'm not really sure what you think my proposed change is. i don't think i've actually proposed anything. i do think it's possible that current recommendations may be low, considering the limits were set some time ago and that people are now recommended to stay out of the sun and shield themselves from UV radiation when they do. for that reason, and the fact that research has accelerated recently, i do think it is an appropriate subject for discussion.

    about cod liver oil, i do take it. and i've been taking it for a few years now before docs have just recently begun recommending it for things like high cholesterol. it's good for a lot more than that, btw. however, i would hesitate to make a general recommendation, because it's also a rich source of fat-soluble vitamin A and those with a tendency to osteoporosis should probably choose a fish body oil for their EPA/DHA requirements.
  12. Feb 19, 2009 #11
    Proton - post what you want. The obscure "cherry-picked" technical presentation or some internet hype. There's no epidemic of deficiency. If you're so worried - take your cod liver oil. Likely you started this line of discussion so you could speak to your pet subject and boast the publications you've read. I'm sure folks are lined up for your recommendations - you giving endorsements now?
  13. Feb 19, 2009 #12
    like i said, i don't take cod liver oil for vit. D. it's not even that great a source, really.

    i don't understand why you guys are getting so upset over this topic. no one seemed to even blink when it was suggested in another thread that iodine consumption may be a couple orders of magnitude too low.

    but since you've got nothing substantive to add, just keep on with the personal attacks. i don't mind, really, your hate is like warm sunshine that invigorates me.
  14. Feb 21, 2009 #13
    "Vitamin D deficiency is now recognized as an epidemic in the United States."

  15. Feb 26, 2009 #14
    Arch Intern Med. 2009 Feb 23;169(4):384-90.
    Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey.
    Ginde AA, Mansbach JM, Camargo CA Jr.

    Emergency Medicine Network, Massachusetts General Hospital, 326 Cambridge Street, Boston, MA 02114, USA.

    BACKGROUND: Recent studies suggest a role for vitamin D in innate immunity, including the prevention of respiratory tract infections (RTIs). We hypothesize that serum 25-hydroxyvitamin D (25[OH]D) levels are inversely associated with self-reported recent upper RTI (URTI). METHODS: We performed a secondary analysis of the Third National Health and Nutrition Examination Survey, a probability survey of the US population conducted between 1988 and 1994. We examined the association between 25(OH)D level and recent URTI in 18 883 participants 12 years and older. The analysis adjusted for demographics and clinical factors (season, body mass index, smoking history, asthma, and chronic obstructive pulmonary disease). RESULTS: The median serum 25(OH)D level was 29 ng/mL (to convert to nanomoles per liter, multiply by 2.496) (interquartile range, 21-37 ng/mL), and 19% (95% confidence interval [CI], 18%-20%) of participants reported a recent URTI. Recent URTI was reported by 24% of participants with 25(OH)D levels less than 10 ng/mL, by 20% with levels of 10 to less than 30 ng/mL, and by 17% with levels of 30 ng/mL or more (P < .001). Even after adjusting for demographic and clinical characteristics, lower 25(OH)D levels were independently associated with recent URTI (compared with 25[OH]D levels of > or =30 ng/mL: odds ratio [OR], 1.36; 95% CI, 1.01-1.84 for <10 ng/mL and 1.24; 1.07-1.43 for 10 to <30 ng/mL). The association between 25(OH)D level and URTI seemed to be stronger in individuals with asthma and chronic obstructive pulmonary disease (OR, 5.67 and 2.26, respectively). CONCLUSIONS: Serum 25(OH)D levels are inversely associated with recent URTI. This association may be stronger in those with respiratory tract diseases. Randomized controlled trials are warranted to explore the effects of vitamin D supplementation on RTI.

    PMID: 19237723 [PubMed - in process]
  16. Mar 1, 2009 #15


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    In practice I have seen an epidemic of low vitamin D. Even down here in sunny georgia. Initially started checking 25 -oh vit d levels in patients who developed severe bone pain when started on bisphosphates and forteo, unless i corrected the vitamin deficiency first, they developed severe pain upon initiation of these meds. Then, there were tons of literture in the pain journals regarding chronic pain and vit d def, more in women then men. I can't tell you how many of my patients have been "cured" of their fibromyalgia ( they come off their analgesics, neurontin, tramadol, cymbalta etc.) once the vitamin d was corrected. Of course, you have to be careful when you find vitamin d deficiency, you have to rule out hyperparathyroidism and or hypothyroidism before just treating the low vitamin d. Sometimes that has been the first sign of hyperparathyroidism/hypo even when serum calcium levels are normal.
    Last edited: Mar 1, 2009
  17. Mar 1, 2009 #16
    Thank you adrenaline, great information to add.
  18. Jul 6, 2009 #17
    interesting that you should mention pain, the same was mentioned here:

    Last edited by a moderator: Apr 24, 2017
  19. Aug 4, 2009 #18
  20. Sep 3, 2009 #19
    I think it's not really easy to have a vitamin D deficiency. If you eat normally, you should get all the Vitamin D you need. You can find http://www.students.sonoma.edu/users/c/charlest/vitamin-recipes.html" [Broken] in eggs, mushrooms or fish. If people took more care of their eating habits, they wouldn't have so many diseases.
    Last edited by a moderator: May 4, 2017
  21. Sep 16, 2009 #20
    Hello friends
    It;s really good question.The best source of vitamin D is sunlight onto bare skin. Dietary sources are usually not that high in vitamin d, even if you eat all those things regularly would would maybe get 50% of your RDI from them. The highest dietary source is cod liver oil by far.
    There are two types of vitamin D put in supplements, D2 and D3. D3 is the more natural form and is far more effective than the D2 variant as it converts to the usable form in the body at a much higher rate.
    Thank you....
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