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Another reason vitamin D is important: It gets T cells going


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vitamin d immune system activation t cellVitamin D deficiency has been linked to a rapidly expanding inventory of ailments—including heart disease, cancer and the common cold. A new discovery demonstrates how the vitamin plays a major role in keeping the body healthy in the first place, by allowing the immune system’s T cells to start doing their jobs. 

In order for T cells to become active members of the body’s immune system, they must transition from so-called "naive" T cells into either killer cells or helper cells (which are charged with "remembering" specific invaders). And, if ample vitamin D is not around, the T cells do not make that crucial transition, a group of researchers led by Carsten Geisler, head of the Department of International Health, Immunology and Microbiology at the University of Copenhagen, found. They draw this conclusion based on their experiments with isolated naïve human T cells.

"When a T cell is exposed to a foreign pathogen, it extends a signaling device of ‘antenna’ known as a vitamin D receptor, with which it searches for vitamin D," Geisler said in a prepared statement. If there is an inadequate vitamin D level, he noted, "they won’t even begin to mobilize."

Although this vitamin requirement might seem like a handicap to the immune system, the researchers proposed that the additional step involving the vitamin D receptor might actually serve an important evolutionary function: keeping T cells from ravaging healthy tissue. "Given that T cells are capable of explosive proliferation, the lag phase imposed by the vitamin D [receptor step] may diminish the risk of unwanted immunopathology," they noted in the study, which was published online March 7 in Nature Immunology (Scientific American is part of Nature Publishing Group).

The body naturally makes vitamin D when the skin is exposed to sunshine (it can also come from eggs and some fish products), but most people in the U.S. are considered to be deficient in the vitamin. In fact, a 2009 Archives of Internal Medicine study found that 77 percent of U.S. adults and teenagers surveyed did not have the estimated minimum healthful level of 30 nanograms per milliliter in their blood. And just three percent of blacks in the survey were getting enough of the vitamin, the 2009 report found.

The new observation of the vitamin’s role in T cell activation could have many implications, including vaccine development (in helping the body to recognize new pathogens) and organ transplant (by discouraging the immune system from attacking a new organ), Geisler noted. Additionally, he added, it "could help us to combat infectious diseases and global epidemics."

Image of a T cell (outlined in red on left) "scanning" another cell to look for invaders courtesy of Carsten Geisler





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  1. 1. Vitamin D3 3:34 pm 03/7/2010

    Yet more miraculous news regarding un-vitamin D ("vitamin D" is a steroid, it has nothing to do with a vitamin). Clearly it is time for the FDA, NIH, CDC, and AA of D to issue some kind of admission that they, essentially, blew it completely. Every day they delay costs thousands of lives, literally.

    Nothing on this earth is more important than maintaining a healthy, natural level of un-vitamin D. Those that have been studying it the longest and most closely insist on a minimum of 50 ng/ml, year round.

    Despite attempts to stall the inevitable recognition of the beyond critical importance of D, one day we can all look back and feel good that we were able to throw more than half of our prescription medicines away because they were basically snake oil. All because small groups of dedicated people persevered and brought us the news.

    Link to this
  2. 2. Vitamin D3 3:38 pm 03/7/2010

    Yet more miraculous news regarding un-vitamin D ("vitamin D" is a steroid, it has nothing to do with a vitamin). Clearly it is time for the FDA, NIH, CDC, and AA of D to issue some kind of admission that they, essentially, blew it completely. Every day they delay costs thousands of lives, literally.

    Nothing on this earth is more important than maintaining a healthy, natural level of un-vitamin D. Those that have been studying it most closely insist on a minimum of 50 ng/ml, year round.

    Despite attempts to stall the inevitable recognition of the beyond critical importance of D, the miracles keep coming. One day we will all look back and feel good because we were able to 86 more than half of our prescription medicines because they were basically snake oil. All because small groups of dedicated people persevered and brought us the news.

    Link to this
  3. 3. patmcgee 3:49 pm 03/7/2010

    I started taking vitamin D supplements a couple of years ago. Last month I noticed that a wart on my elbow had disappeared. After several years of trying to various treatments to get rid of it, I had ignored it for a year or so. When last seen, it was about the size of a dime.

    Yes, correlation isn’t causality, and one swallow does not a summer make. But it’s enough to get me to wonder. And I know that immune response is somehow involved in getting rid of warts.

    Pat McGee

    Link to this
  4. 4. RWS-GR 8:19 pm 03/7/2010

    How has the fear of exposure to the sun (cancer) resulted in lack of natural D? See the studies of D (1,2 and 3), they’re not the same. Choose your poison, mine’s more sun — better odds.

    Link to this
  5. 5. ajkelly 8:48 pm 03/7/2010

    I would advise you to take the Vitamin D. We know of no harm, other than the potential overdose with extremely high intakes (at least >10,000 units /day), in taking Vitamin D3. Melanoma is one of the most common cancers in younger people and can be fatal if not caught in time. I know, my father died of metastatic melnoma at the age of 50.

    Besides, in our lab, we see some people with low Vitamin D levels who work outdoors. They should have higher levels, but they don’t. And not all of that can be explained by sunblock, or covering up the skin wtih clothing, because not all of them do. We wonder if there are some people with a "broken Vitamin D factory" in their skin. Perhaps this is a genetic defect that runs in certain families? Or perhaps there are other missing activating factors (other phytonutrients?) that don’t allow the formation of active Vitamin D?

    We already know that some people with absorption problems in their gut (like wheat gluten allergy) don’t absorb vitamin D very well, even if it is in their diet, and either need high oral doses or sub-lingual Vitamin D supplements.

    Link to this
  6. 6. BJ Bonobo 9:50 pm 03/7/2010

    The body naturally makes Vitamin D when the skin is exposed to sunshine . There are places in the world and times of year when this is difficult to do but exposing the entire body to hours of bright sun per day is not necessary. People who get into the daylight on a regular basis have no problem with deficiencies !

    Link to this
  7. 7. BarkingMad 10:01 pm 03/7/2010

    Several reports have popped up about people in sunny places like Florida who are low in D.
    My best guess is not an absorption problem, but a measurement problem. Also, there would be disease clusters correlated to the low D populations. I just don’t believe people are that vigilant with sunblock, after all it wears off a in a few hours.
    There are correlations with diseases that decline as one travels toward the tropics. This is not the same as saying there’s a D deficiency. Maybe it’s something else. Don’t go crazy with popping the pills until the inconsistencies get worked out.

    Link to this
  8. 8. jtxl 11:50 pm 03/7/2010

    Any thoughts on a recomended dosage for someone with rheumatois arthritis- overactive t-cells going after healthy tissue

    Link to this
  9. 9. Lifeguard 11:58 pm 03/7/2010

    I am a 41 year old former beach lifeguard. I spent huge amounts of time in the sun when I was younger. In my thirties, I stopped doing that, went back to school in my late thirties for some post graduate stuff. Starting in my mid to late thirties I began having problems with recurrent colds, sinus problems, etc. Last Spring, I had the worst sinus infection, could not shake it. Went to an Internal Medicine doctor for it and in addition to the usual anti-biotics, he drew some blood to test. Came back positive for EXTREMELY LOW vitamin D. I was put on a prescription strength vitamin D pill, a generic version of something called "drisdol." Each pill is 50,000 IU vitamin D. I was prescribed 100,000 IU a week, two pills.

    Results were nothing short of dramatic. My sinuses cleared up, the frequent colds and such that I had been experiencing cleared up. I also had a skin condition I had developed in my late thirties completely clear up. The stuff also boosted my mood and gave me more energy.

    I decided to get recertified as a Lifeguard last Spring as a result of this. At age forty, I got recertified…the next youngest kid in my class was probably 18. I made it thru no problem and got a job at an outdoor waterpark last summer. Did NOT USE ANY SUNSCREEN whatsoever. While taking 100,000 IU a week. By the end of the summer I felt darn good.

    I think it takes a two pronged approach if you are the typical "indoor American" that you have to admit, most Americans are these days. That is, I believe taking vitamin D supplements, combined with regular sunshine exposure, is the best approach. I refuse to use sunscreen and I urge others to not use the stuff unless you have a history of melanoma or something.

    Get your vitamin D anyhow you can get it, but get it. I knew as far back as my teenage days as a Lifeguard I felt much better when I had a tan. Slept better, looked better, mood was better, immunity was better, EVERYTHING was better when I have a tan.

    End of story. Stop being afraid of the sun. The sun is good for you.

    Link to this
  10. 10. Lifeguard 12:04 am 03/8/2010

    As much as possible I would say. 50,000 IU a week minimum. Get all the sun exposure you can this spring and summer too.

    Link to this
  11. 11. jtxl 12:08 am 03/8/2010

    Sorry about the previous spelling- it is Rheumatoid. This article is very interesting since my arthritis took a very destructive turn and went after my eyes at the same time that I was diagnosed with a D deficiency. I took the prescription and have followed up with 800iu in a daily multi but I think it may be time to consider a higher dose. what is the difference between D 1, 2 and 3. I have always seemed to crave time in the sun and would tan at least a few times a week to keep my energy up. Funny that my friends all laughed at me when I told them I needed to tan. I had only stopped a few years ago when I hit my 40s and started to worry about wrinkles. I now think it is time to reconsider- I can cover my face.
    Thanks Lifeguard- I took the presc temp to get numbers up but with this information I now know I need to do more.

    Link to this
  12. 12. Lifeguard 12:15 am 03/8/2010

    I could see how you could live in Florida and still have low vitamin D, very easily in fact. Just because you live in Florida does not necessarily mean you spend all that much time outdoors exposed to the sun. In fact, many Floridians spend a lot of time indoors where its nice and cool with the AC going from spring to fall.

    Also, obesity contributes to vitamin D deficiency. You could live in Florida and unless you s pend a lot of time outdoors in the sun, like a surfer or outdoor lifeguard or something along that line, not get enough vitamin D

    Bottom line, no matter where you live, two pronged approach. Supplements and lots of sun exposure. Ditch that sunscreen that is making the sunscreen manufacturers wealthy. I wont use the stuff.. Built a tan up gradually. Start 15 minutes each side, front and back, per day. Stick with that for a week. Then go to twenty minutes a day, do that for a week, Then you should probably be able to handle thirty minutes front and back daily all summer long.

    Thats how I do it. Start gradual and build the tan up. I take one day and stay out of the sun per week and give my skin a rest. Two days a week out of the sun is probably OK as well.

    Bottom line is God did not create humans to live indoors all the time, being physically sedentary and not being exposed to the sun. God made humans to walk a lot, be outdoors a lot, to move around a lot and to be physically active, not sedentary.

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  13. 13. Lifeguard 12:20 am 03/8/2010

    Just protect your eyes when sun tanning. The eyes I wear high end polarized sunglasses. Sometimes I still wear a broad brimmed hat but if I get enough "time on sun" that broad brimmed hat doesnt matter. I still get tons of sunlight. I take my shirt off,

    I recommend getting blood work done formally. That way, if it comes back low your doc is obligated to prescribe you the good stuff, the prescription stuff and not the OTC vitamin D. I think most OTC is fine, most Ive seen is D3 form, which is fine but the prescription D is just mega powerful, high dosage stuff. Its better because its high potency. Gets your levels up faster.

    This stuff also helps depression btw.

    Link to this
  14. 14. DRVAMAN 10:09 am 03/8/2010

    This is a tricky situation. Vast majority of patients who have low levels of vitamin D have absolutely no symptoms at all. The point I would like to emphasize, is not to wait for symptoms to appear before having your vitamin D level checked. Current research strongly suggests that there is a strong correlation between multiple bone diseases, diabetes, cancers, multiple sclerosis, heart disease, and depression. Even in the absence of symptoms your vitamin D level may be low.

    Most vitamins can be obtained by eating a well-balanced diet. You may be interested to know that what we call vitamin D is actually a hormone and not a vitamin, therefore it is virtually impossible to get adequate amounts of vitamin D during the fall and winter months in Europe and the US. My friend Dr. Benjamin Newman MD, Maine has dedicated 40 years in Vitamin D research feels that everyone should have their vitamin D level checked and start taking the appropriate supplementary dose of vitamin D based on their blood value.

    Link to this
  15. 15. hastigo 4:51 pm 03/8/2010

    I subscribe to almost everything I’ve read in this commentary section. And love the article…one of hundreds flooding out in the last 2-3 years. All positive for higher doses.
    And am enthusiastic about 25-OH(hydroxy)cholecalciferol
    supplementation. ..and testing –too!

    Personally use 5000iu/daily…test at mid normal for the above (don’t get tested for 1, 25 Oh-cholecaciferol…expensive and misses the mark.)

    And hope that the hypo-vitaminosis D endemic which the Western World has suffered for at least a century is finally come to a well deserved and final end.

    BUT…please(?) let’s not get nuts.

    If you have a medical condition (osteoporosis, rickets et al or even something not quite so serious) which calls
    for over about 5, 000 iu a day…by all means follow the medical advice.

    But for most of us stick at no more than…the 5, 000iu which was recommended for me (John Cannell MD, Vitamin D Council) and which I’ve taken for 4 years.
    I admit to a bit of initial trepidation about the higher doses… until I was reassured by testing.
    [Remembering that the RDA was (is?) 400iu daily.
    absolutely inadequate.]

    BUT…don’t get us a lot of reports of illness from hyper-supplementation (remember the tryptophan debacle?);
    Or the fear-mongers will get all tooled up again and the FDA will vacillate and probably cave to keeping the inadequate RDA. They cave easy, y’know.

    Use good sense.

    james t MD

    But the advice for mega-doses must be taken with a grain of caveat.

    Link to this
  16. 16. Lifeguard 4:23 am 03/9/2010

    JamesMd, the high doses are for individuals who have been formally diagnosed with low vitamin D levels by their physician via blood work. Despite being an MD, you sound rather ignorant and to be honest, afraid of prescribing 50,000 IU type doses to patients. 50,000 IU a week or even more is what Ive been prescribed by very knowledgeable doctors in Charlotte, NC. I did not have rickets.

    It can be difficult to get vitamin D levels up once they get really low….sometimes high dosages is the only way to get levels boosted back up.

    You sound like another doctor who is simply afraid you are going to get sued.

    Link to this
  17. 17. Tiqueo10 12:00 pm 03/9/2010

    2 Questions:
    Is "vitamin" D one of the fat-soluble ones?
    How much can we get from foods?

    I make a point of having adequate fats to absorb many nutrients (I even make a drink based on carotenoids and EFAs).

    I also love fatty fish and often request the salmon bellies at the deli which are loaded with the good stuff.

    Link to this
  18. 18. DRVAMAN 4:55 pm 03/9/2010

    In order to enjoy optimal health, we should maintain a
    vitamin D blood level of =5099 ng/ml. Without sun
    exposure, to reach a level of 50 ng/ml requires taking a
    5,000 IU/day vitamin D supplement. There are two kinds of
    vitamin D supplements: vitamin D3 (cholecalciferol), the
    kind our skin makes, and vitamin D2 (ergocalciferol), a
    synthetic variant made by irradiating plants. Vitamin D2 is
    only 1030% as effective in raising 25-hydroxyvitamin D
    blood levels compared to vitamin D3, leading the authors
    of a recent study conclude, "Vitamin D2 should not be
    regarded as a nutrient suitable for supplementation or
    fortification" (Am J Clin Nutr 2006;84:694697).

    Concerns about vitamin D toxicity are overblown, along
    with those about sun exposure. As one researcher in the
    field puts it, "Worrying about vitamin D toxicity is like
    worrying about drowning when youre dying of thirst." The
    LD50 of vitamin D in dogs (the dose that will kill half the
    animals) is 3,520,000 IU/kilogram. One can take a 10,000
    IU vitamin D supplement every day, month after month
    safely, with no evidence of adverse effect. (Am J Clin Nutr
    1999;69:842856). A person must consume 50,000 IU a
    day for several months before hypercalcemia (an elevated
    calcium level in the blood, which is the initial manifestation
    of vitamin D toxicity) might occur. Vitamin D in a
    physiologic dose (5,000 IU/day) prevents the build up of
    calcium in blood vessels. (Circulation 1997;96:1755

    1760). If one takes 10,000 IU of vitamin D a day and
    spends a lot of time in the sun, it would be prudent to check
    vitamin D blood level to ensure that it does not exceed 100
    ng/ml.

    Sensible sun exposure should be encouraged, not maligned.
    If one avoids sunburn, the suns health-giving benefits far
    outweigh its detrimental effects. A large body of evidence
    indicates that sunlight does not cause the most lethal form
    of skin cancer, malignant melanoma. A U.S. Navy study
    found that melanoma occurred more frequently in sailors
    who worked indoors all the time. Those who worked
    outdoors had the lowest incidence of melanoma. Also, most
    melanomas appear on parts of the body that are seldom
    exposed to sunlight (Arch Environ Health 1990;45:261
    267). Sun exposure is associated with increased survival
    from melanoma (J Natl Cancer Inst 2005;97:195199).
    Another study showed that people who had longer lifetime
    exposure to the sun without burning were less likely to get
    melanomas than those with less exposure (J Invest
    Dermatol 2003;120:10871093.)

    The rise in skin cancers over the last 25 years parallels the
    rise in use of sunscreen lotions, which block vitamin D-
    producing UVB radiation but not cancer-causing ultraviolet
    A radiation (UVA). (Newer sunscreen lotions also block
    out UVA.) Each year there are 8,000 deaths from
    melanoma and 1,500 deaths from nonmelanoma (squamous
    and basal cell) skin cancer. Surgical excision of
    nonmelanoma skin cancers cures them, except in rare cases
    where the growth has been allowed to linger for a long time

    and metastasize. Dr. John Cannell, Executive Director of
    the Vitamin D Council, makes this point: 1,500 deaths
    occur each year from non-melanoma skin cancer, but 1,500
    deaths occur each day from other cancers that vitamin D in
    optimal doses might well prevent. (The Vitamin D Council
    website is an excellent source of information on vitamin
    D.)

    The U.S. government and its citizens currently spend
    $2,000 billion dollars ($2 trillion) on "health care," i.e.,
    sickness care, each year. The cost of taking a 5,000 IU
    supplement of vitamin D every day for a year is $22.00.
    The cost for 300 million Americans taking this supplement
    would be $6.6 billion dollars. The number and variety of
    diseases that vitamin D at this dose could prevent, starting
    with a 50 percent reduction in cancer, is mind-boggling. If
    everyone took 5,000 IU/day of vitamin D, the U.S. "health
    care" industry would shrink. It would no longer account for
    16 percent of the gross domestic product.

    Health food stores typically do not sell vitamin D3 in 5,000
    IU tablets, but they are readily available online. BIO-TECH
    Pharmacal produces both 5,000 and 50,000 IU tablets of
    Vitamin D3, which online sites sell. Some people prefer to
    take one 50,000 IU table a week (equivalent to 7,100 IU a
    day) and a three-day course of 150,000 IU vitamin D at the
    first sign of a cold.

    Link to this
  19. 19. Wayne Williamson 5:38 pm 03/9/2010

    interesting article and good comments….time for me to get a checkup;-)

    Link to this
  20. 20. Lifeguard 9:32 pm 03/9/2010

    You cant get much vitamin D from food. Some, but not much. You can get your RDA of it, maybe a little more, but thats all. Enough to prevent rickets, basically.

    Unless you want to move to Norway and eat oily fish like Mackeral every single day for the rest of your life, there are basically two ways to get higher dosages of vitamin D. The first is what nature intended…sunshine exposure…regular exposure. And the second is quality vitamin D supplements. Cod liver oil is good, but personally, at the minimal doses recommended these days (teaspoon, usually), Im skeptical you can get enough vitamin D with cod liver oil. In the old days, people took a full tablespoon full of cod liver oil year round. Plus got sun exposure. I asked my dad about this and he told me how it used to be.

    A lot of doctors are just afraid of being sued and just want to push drugs and aren’t into prevention and nutrition enough. Many are afraid. Dont listen to them and their anti-sun exposure bunk. Just dont get sunburned.

    Link to this
  21. 21. balmerhon 9:52 pm 03/9/2010

    I would not be so bold as just state get all the sun, and forget about the skin cancer! That’s as crazy as saying, get no sun ever and don’t take extra Vit. D. There is an big upsurge in skin cancer in younger people. Everyone is Different. But to say get all the sun you want, unless you have a history of skin cancer in your family, just isn’t a responsible thing to be saying. You are one anecdotal case. There are zillions of anecdotal ‘evidence’ – all different, and oppositional to one another. Do not make blanket statements. State your own evidence, period. Let people do what they will with it. Thank you!.

    Link to this
  22. 22. Lifeguard 11:06 pm 03/9/2010

    I will make a blanket statement and that is, most Americans are like vampires. They work indoors all day long, do not work on farms anymore, we are deluged with ads and scare tactics for high protection sunscreen products. The average American is terrified "they might get skin cancer if they get some sun." Its bull and its wrong to let the sunscreen companies scare Americans as they do.

    The sun is good for you. Period. The ones who get skin cancer are the ones who never get any sun, go out and try to get it all in a couple days and get burned like lobsters. That is not suntanning.

    There is not a huge upsurge in skin cancer among young people btw. Most young people dont even go outside in the first place. Most spend all their time indoors, playing video games.

    Screw the "experts," get your sunshine and your vitamin D. Take the supplements too. Americans are radically deficient in vitamin D.

    Link to this
  23. 23. zann 5:11 pm 03/10/2010

    My neurologist has me taking 50000IU a week. I have a chronic vit D deficiency even though gardening is my hobby. I am much more mobile and suffer much less muscle weakness and pain since she started me on this regimen.

    Link to this
  24. 24. Vic 11:04 pm 03/11/2010

    For a complete physical/chemical description of the synthesis and DNA acivation in the human body, see SciAm Magazine of November 2007.
    Article entitled: "Cell Defenses and the Sunshine Vitamin" by Tavera-Mendoza & White. You can access it at:
    http://www.scientificamerican.com/blog/post.cfm?id=another-reason-vitamin-d-is-importa-2010-03-07

    Link to this
  25. 25. WilliamGulvin 10:18 pm 03/13/2010

    Let me add one more anecdote to the chorus. For decades I felt that there was something "missing" in my diet & health, and for decades I cautiously and skeptically sampled many of the more plausible supplementation fads that came along, to little or no positive effect. Based on emerging research, about four years ago I started taking extra vitamin D3 (about 700-1000 IU/day). My general heath immediately started to noticeably improve. So I gradually increased the daily dosage and a host of minor but annoying health problems improved almost in lock-step with the increasing dosage. I’ve been taking 5000 IU (summer)-10000 IU (winter) for the last two years, and I am now far healthier that I’ve ever been in my 40 years of adult life. Virtually all nagging minor infections from seborrheic dermatitis to toenail fungus have completely resolved and all things epithelial (skin, mucus membranes, gut etc.) are in far better condition than ever before. No colds or flu, either, and at 60 my blood work numbers are optimal across the board. As far as I’m concerned, if ever there was a panacea, vitamin D is it.

    Moreover, it has certainly been bad for business for both the doctors and drug companies. I’ve not been to the doctor for anything more serious than a check-up in two or three years (I use to see the doc rather too regularly for several things), and two years ago I successfully discontinued a prescription that I’d taken for years and that cost over $10/day. Heck, I rarely take aspirin any more.

    BTW, a good dosage rule is 1000 IU/day for every 25 – 33 pounds of body weight. More in winter and definitely more if one has darker skin. And for all you vegetarians, commercial vitamin D3 is made by irradiating lanolin with, guess what, ultraviolet light. Which may well be *why* it has been so overlooked by researchers until recently. Not only is no-one going to make much money selling vitamin D (the aforementioned Bio-Tech Pharmacal is a good vendor, but they don’t fund research grants), but a lot of people and organizations actually stand to loose money if everyone gets their vitamin D levels up to optimum.

    It’s good stuff.

    Link to this
  26. 26. Samadams 12:31 pm 03/14/2010

    The observation that clusters of disease would follow clusters of vitamin D is precisley what led to the current research into vitimin D and the imune system. Most blacks here in the northern climate have chronic vitimin D deficiencies and have higher levels of precisley the diseases blamed on it. The popular media blames it on disparieties in the health care system but it looks like there is more involved then this. I do not deny that blacks get treated worse in the health care system, I am white and I have observed it myself in the hospital emergance room. That said, I maintain that the disease propencity is a confluence of factors.

    For us whites as well as blacks, cold season and flu season is the winter. Follow industrial absentia from illness if you doubt this.

    Link to this
  27. 27. Samadams 12:32 pm 03/14/2010

    The observation that clusters of disease would follow clusters of vitamin D is precisley what led to the current research into vitimin D and the imune system. Most blacks here in the northern climate have chronic vitimin D deficiencies and have higher levels of precisley the diseases blamed on it. The popular media blames it on disparieties in the health care system but it looks like there is more involved then this. I do not deny that blacks get treated worse in the health care system, I am white and I have observed it myself in the hospital emergance room. That said, I maintain that the disease propencity is a confluence of factors.

    For us whites as well as blacks, cold season and flu season is the winter. Follow industrial absentia from illness if you doubt this.

    Link to this
  28. 28. xxdb 3:28 pm 03/15/2010

    Every winter I also used to get several colds and respiratory infections I could not shake off till I started taking 5,000 IU per day between october and march two years ago. I have had a single respiratory viral infection which lasted all of two days.
    Similarly, since I started giving my two kids 1,000 IU per day during the same period, they don’t seem to get sick. I have also noticed a mood lift and a feeling of vigor.
    This is all very unscientific, but the evidence is mounting that vitamin D is not optional.

    Link to this
  29. 29. nannied 7:20 pm 03/15/2010

    i was diagnosed last year wiyh non hodgkins lymphnoma cancer i had a regimen of chemo an radiation there are no signs of cancer now i ‘am on a 50.000 units of vitamin d weekly it has pepped my whole immune system mentally an physically

    Link to this
  30. 30. Crowemagnum 2:28 am 03/20/2010

    Whoever came up with the idea that vitamin D is a steroid must be on steroids for it is naturally made on the top of the forearm or on the top of the feet indirect sunshine (not through a window) for 15-20 minutes once a day between 9am-4pm. The interactions between the sunlight and chemicals on top of the skin creates the vitamin D which is then absorbed through the skin into the body.

    We can thank the sunscrene industry for so making people panic about the sun when in reality, we need the some sunshine everyday.

    Link to this

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