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Biotech Science

Vitamin D Deficiency Behind Many Western Cancers? 478

twilight30 wrote us with a link to an article in the Globe and Mail. If further study bears out the findings, new research into the causative agents behind disease and cancer may have a drastic impact on the health of citizens in Canada and the US. According to a four-year clinical trial, there's a direct link between cancer and Vitamin D deficiency. "[The] trial involving 1,200 women, and found those taking the vitamin had about a 60-per-cent reduction in cancer incidence, compared with those who didn't take it, a drop so large — twice the impact on cancer attributed to smoking — it almost looks like a typographical error. And in an era of pricey medical advances, the reduction seems even more remarkable because it was achieved with an over-the-counter supplement costing pennies a day. One of the researchers who made the discovery, professor of medicine Robert Heaney of Creighton University in Nebraska, says vitamin D deficiency is showing up in so many illnesses besides cancer that nearly all disease figures in Canada and the U.S. will need to be re-evaluated. 'We don't really know what the status of chronic disease is in the North American population,' he said, 'until we normalize vitamin D status.'"
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Vitamin D Deficiency Behind Many Western Cancers?

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  • by lems1 ( 163074 ) on Sunday April 29, 2007 @04:40AM (#18917337) Homepage
    Now I'm waiting for another research showing that the intake of vitamin D causes some other serious illness...

    So typical.
    • by Xiroth ( 917768 ) on Sunday April 29, 2007 @05:13AM (#18917479)

      Now I'm waiting for another research showing that the intake of vitamin D causes some other serious illness...

      OK. Skin cancer. The main source of vitamin D in humans is through exposure to sunlight. Increase that without being careful and your risk of skin cancer goes up. Also, vitamin D overdosing from supplements is entirely possible and does have nasty side effects, although it's not possible from natural production due to exposure to sunlight.

      There we go, cynicism confirmed, and it wasn't as bad as all that. Now, let's get down to reality: as vitamins, the vitamin D group have been identified as essential for human nutrition. Not useful, essential. As in, we would die without it. There's strong evidence, in fact, that the reason people that moved away from the equator developed paler skin was to maintain high production rates of vitamin D. So, quite frankly, even if the intake of vitamin D killed us, we'd have to have it as if we don't take it we die anyway, therefore the entire point is moot.
      • Re: (Score:2, Informative)

        by Anonymous Coward
        There's strong evidence, in fact, that the reason people that moved away from the equator developed paler skin was to maintain high production rates of vitamin D. So, quite frankly, even if the intake of vitamin D killed us, we'd have to have it as if we don't take it we die anyway, therefore the entire point is moot.

        The 'skin colour' and latitude argument has been dismissed already by evolutionary biologists, not least because humans haven't actually been in Northern Europe for long enough for evolution
        • by Bryan Ischo ( 893 ) * on Sunday April 29, 2007 @06:53AM (#18917815) Homepage
          Name one race from a northern climate that has brown or black skin. You can't. There aren't any. Now name a race from an equatorial region that has white or light skin. Once again, you can't.

          I'd say this is pretty strong evidence for the GP's point. Sure, there will be variations among races at the same latitude, I wouldn't be surprised if some equatorial people were darker than others. But I would also be surprised if there wasn't a STRONG correlation between latitude and skin color. It would seem really, really unlikely that this was "caused by genetic variation of a few settlers." Yeah, the light colored setters just randomly happened to move north, and the darker people stayed south. Sure.

          And people weren't in northern europe long enough for evolution to have played a role? OK then how about China? Northern Chinese are very light-skinned, I know this from experience. And surprise, surprise - southern Chinese are alot darker. And don't you think that a 60% greater chance of disease due to vitamin D deficiency would be a strong evolutionary pressure? Strong enough to act over relatively short time periods on the evolutionary scale perhaps?

          Anyway, if your evidence for this evolutionary biologists' "dismissal" of skin color's correlation to latitude is one book, that's pretty weak. Of course, it's still more evidence than I can submit.
          • by SerpentMage ( 13390 ) on Sunday April 29, 2007 @09:28AM (#18918521)
            Inuit... Inuit have relatively dark colored skins...

            http://www.smh.com.au/news/world/climate-forces-in uit-onto-thin-ice/2006/05/26/1148524886121.html [smh.com.au]

            And Inuit have been living in the North for many thousands upon thousands of years (50,000 I think). Actually I am always amazed at how dark their skin is comparing to where they live. It's not like you are going to see a bunch of Inuit suntanning on the tundra...

            A skin near the equator that is light colored? Hmm... How about Amazon natives? http://bbs.keyhole.com/ubb/z0302a1700/amazon.jpg [keyhole.com]

            The Amazon is about as close to the equator that you can get and their skin is relatively light colored when compared to say the skin color of an individual from Africa. And last I heard Amazon natives have been there for many many many thousands of years.

            So the nutshell is equator = darkness of your skin color is HOGWASH! Want me to prove it even further? How about the aboriginals of Australia when compared to an individual from Malaysia? Aboriginals are much much darker and further away from the equator than individuals from Malaysia....
            • by Zaphenath ( 980370 ) on Sunday April 29, 2007 @09:56AM (#18918679)
              The reason I have heard cited for why people such as the Inuit, or Italians have darker skin is because of fish intake.

              Coastal peoples, such as the Inuit, have a high intake of fish in their diet, and so get a lot of Vitamin D. Same goes for the Italians.

              My guess for the Amazon natives having lighter skin would be that they live in the jungle? Not out in the plains, and so they would still be receiving less sunlight than people living in the Savannah. Just a guess, but it fits with the theory.

              So, light skin is still associated with low Vitamin D levels. If there is strong sunlight, or a large amount of fish in the diet, darker skin is advantageous.
              • by shawb ( 16347 ) on Sunday April 29, 2007 @10:36AM (#18918915)

                My guess for the Amazon natives having lighter skin would be that they live in the jungle? Not out in the plains, and so they would still be receiving less sunlight than people living in the Savannah. Just a guess, but it fits with the theory.


                Bingo. Dense rainforest canopies block a very significant amount of light. IIRC about 5% makes it through to the lower levels where people would reside. Jungles are quite dark, something that doesn't come through in pictures and movies due to compensating with exposure time and aperture size.
            • Not magic (Score:4, Insightful)

              by DrYak ( 748999 ) on Sunday April 29, 2007 @05:16PM (#18921669) Homepage
              Nobody said that, skin colour of all ethnic groups will automagically instantly adapt to the amount of sunlight they receive in their location.
              Nor that you could predict the latitude where some ethnic groups lives, down to 1 precision, based only on skin colour.

              What the parent says is that *there seems* to be some variation of skin colour which may follow some pattern which can be put in relationship with some factor like sunlight exposure. Like always with nature, there are never "nevers" or "always". Only "tendencies" and even if there's so much variation between skin colours, you can't deny that paler complexion are a little bit more frequent in region with less sunlight exposure.
              Amazon natives MAY be a lot less dark than other people living in the equator, they ARE STILL a little bit more tanned than Swedish people.

              Also the whole point of the original poster was to say that this tendency of distribution could be partly caused by the fact that on one hand, too much sunlight kills because UV are cancerigens, and not enough kills too because of Vitamin D deficiency. Thus people will tend to have skin colours grossly adapted to the region where they originate from even if there's a lot of variation (partly due to the fact that all this is recent history and there hasn't been enough time for selection to discriminate more strongly, in fact given the local climate variation and the degree of additional modulable protection produced by clothes it's not necessary that skin colour needs more adaptation for regions).

              As a side note, in practical medicine, we do see, for example, occurence of some problems such as osteoporosis (brittle bones due to deficiency in vitamin D) happening with a higher frequency in women originating from northern Africa (skin "somewhat tuned" for high sun exposure by recent evolution, but hiding under too much clothes for religious reasons and not getting enough sun to produce vitamin D) than with european women (wear also a lot of clothes for cold / sunburn protection, but the light that gets through paler skin is a little bit more for Vitamin D synthesis).

              Aboriginals are much much darker and further away from the equator than individuals from Malaysia

              But on the other hand both gets way much more sun than people in Denmark. Or northern China. Or Siberia.
              And happen to be, on the average, darker than those people, even if there's variation than can't be only explained by the amount of sun exposure alone.
            • Your couple of anecdotal examples aside, the major trend in clearly towards darker skin nearer the equator. Look at any of the countless skin color maps [wikipedia.org] that researchers have generated.
          • Re: (Score:3, Insightful)

            by mackyrae ( 999347 )
            The north's not the only "far the from the equator" place. How about southern parts of Africa? Are the people there really pale because of Vitamin D? No? Oh, that can't be it then.
            • by BeanThere ( 28381 ) on Sunday April 29, 2007 @02:18PM (#18920289)
              Several counter-points:

              - Southern and particularly South Africa are HOT, very hot, and it's sunny almost every day of the year. Summer is baking hot for months. Rudimentary research would've turned that up.

              - The black people of South Africa are here as a result of a relatively recent massive migration of the Bantu peoples from around the Cameroon area that spread first East and then South. In South Africa they have been here probably not more than 1500 years.

              - The indigenous people of South Africa that have been here for a long time (10,000+ years), e.g. the Khoesan, DO in fact have lighter complexions than the Bantu peoples that came from the equatorial regions.

              - Even the 'black' people of South Africa ARE in fact lighter than their self-same relatives from up North - in fact generally speaking the closer you get to the equator, the darker the black people get. (That itself appears to be another strong argument for the Vitamin D correlation, although it's not that cut and dry because some, or perhaps much, of the lightening of the blacks in South Africa is due to generations of interbreeding with e.g. Khoesan peoples.)
        • We are Caucasians. (Score:5, Informative)

          by Futurepower(R) ( 558542 ) on Sunday April 29, 2007 @08:08AM (#18918111) Homepage
          Our white skin color comes from the Caucasus mountains, north of Iran. That's why white people are called Caucasians. I had a woman friend whose ancestry was from northern Iran, and it was amazing to see how white she was, in a way I thought was beautiful. Comparing her skin and mine, it was easy to see that I am a mixture of Caucasian and something else.

          Probably the reason northern people are white is that black people inter-marrying with a high concentration of white people tends to produce lighter-skinned new generations.

          All humans apparently spread from an original migration from Africa, but the people who initially migrated tended to continue to migrate, and migrated much more than those who initially stayed in Africa.
          • Re: (Score:3, Informative)

            by lawpoop ( 604919 )

            We are Caucasians. Our white skin color comes from the Caucasus mountains, north of Iran.

            Are you saying that all 'white' people alive today derive their white features from an ancestor in the caucus mountains? That was a popular theory from about 50-100 years ago, but I haven't heard of any researcher that sticks by that today. Yes, there are white people in the caucus mountains, but there's no evidence to believe that white skin developed there, over and above any other place in Europe.

        • Re: (Score:2, Informative)

          by noemore ( 959325 )
          http://en.wikipedia.org/wiki/Gloger's_rule [wikipedia.org] that's my counter arguement.
        • by happyemoticon ( 543015 ) on Sunday April 29, 2007 @11:29AM (#18919217) Homepage

          That's funny, cause I taped some lectures at a major research institution back in '04 where an evolutionary biologist cited the link between skin color and latitude. So apparently not all evolutionary biologists subscribe to this belief.

          Too little sun exposure causes a Vitamin D deficiency. When women have Vitamin D deficiencies, they become less fertile. And interestingly, if I recall correctly, too much sun exposure interferes with women's antral follicle development - the ones in the ovaries, not on the skin. Therefore, there is the potential for selective pressure to be both not too dark and not too light.

          Is natural selection - note that I said Natural Selection, not evolution - fast enough to cause the suppression of darker-skinned people at the poles and lighter-skinned people at the equator? Well, if I started off with a population where everyone's blood type was either AB, A, or B, and I sterilized all of the people with B alleles, the population would soon be all type A. No other factor has as direct an impact on a population's genes than fertility, by definition. Forget skin cancer. Skin cancer won't prevent most people from having children. Having no viable eggs will.

          So nobody's saying those strange cosmic rays created the variation we see in people's skin tones. But it's daft to push aside the direct impact that skin color and latitude have on fertility, and the large body of circumstantial evidence we have in the form of human geography.

        • by fyngyrz ( 762201 ) * on Sunday April 29, 2007 @02:13PM (#18920245) Homepage Journal
          The 'skin colour' and latitude argument has been dismissed already by evolutionary biologists, not least because humans haven't actually been in Northern Europe for long enough for evolution to have played a role in developing the pale skin colour found there.

          Evolutionary change can occur very quickly; we've seen this. Deer moved to an island shrank in size over the course of several generations. Insects change their colors to cope with soot. Outright mutations only take one generation, no matter what changes.

          So wherever you got your "information", stop going there. They don't know how evolution works. It isn't just gradual change, though it encompasses that too.

          All that aside from the circumstantial evidence.

      • by arivanov ( 12034 ) on Sunday April 29, 2007 @06:47AM (#18917791) Homepage
        Yep.

        You also forgot to add that besides a number of major cancers Vitamin D defficiency also has clear links to obesity as well. Its defficiency in childhood results in soft tissue growth overtaking bone development and very quickly going down the fat kid spiral. Nearly every obese kid aged 7-14 has classic X legs which are a clear indication that he/she has gone through vitamin D defficiency at some point in their life (usually past the age of 2, earlier results in O-shape). For every 1 person the "Dip your child into factor 40 cream" cretins save from skin cancer tens will die of other vitamin D defficiency related illnesses.

        Just look at Australia. It was the first to go into the "hide in the shade" overdrive and we constantly get Australian studies quoted about the dangers of sun onto us (without any corrections for the fact that the numbers should be corrected for different lattitudes). It now is the world leader in obesity overtaking the US.

        It is proudly followed by surprise surprise - UK which has taken all AU studies and is applying them blindly despite being at way further from the Equator. It is quite funny, every time I get some "scary" number quoted I ask the origin and it ends up being Australia from the height of the Ozone hole period. In the UK there is a further complicating factor - GP incompetence. None of the UK GPs and health visitors carries out the standard checks for rachitis on children. Further to this, if you ask them they tell you not to worry. If a child in the age 3-18 months get an abnormal hair loss, they tell you to go get special shampoo for him instead of running blood tests (which the rest of EU does).

        • by Winckle ( 870180 )
          X legs? Can you elaborate?
        • Re: (Score:2, Insightful)

          by Anonymous Coward
          The GPs are right. Rickets is practically non-existent in developed countries now among normal people. Almost any animal fat will contain vitamin D. No reasonable individual avoids sunlight enough to get rickets, it only really occurred in london during the london smog, when there was a very small amount of sunlight, AND no artificial sources.
          A single 400 iu tablet (which you can buy at any pharmacy OTC) of vitamin D can prevent rickets for more than 2 months. How can you possibly think that you know
          • by arivanov ( 12034 ) on Sunday April 29, 2007 @09:02AM (#18918391) Homepage
            Disagree.

            In the UK, in same nursery as my kid when he was 3 there was at least one case of Rickets worse than anything I have seen in the 3rd world. Locally born, locally grown.

            The really disgusting point here is that the nursery in question was running the daycare for a UK health trust so the child was a child of UK healthcare professional.

            All symptoms - skull deformity, chest deformity and O-legs so pronounced that a small dog could jump through between the knees when the child was standing straight with heels together.

            And that is not the only one I have seen in the UK (though clearly the worst one).

            I agree with you regarding the presense of D in the diet, but there is an important point here - when taken in its normal form it requires activation by UV in the skin. Only formula milk contains preactivated D (aka D3). Even most vitamin supplements contain the non-active form. In order for it to be activated one should get at least 35 mins unhindered (no cream) summer sun per day in UK lattitudes (on average for a caucasian white, adjust up for a darker skin). Currently, the schools and nurseries splat kids with factor 32+ and do not allow them out without it (and/or mandate long trousers and long sleeve in the summer months). As a result, how much vitamin D you have taken in food is irrelevant, it is not getting activated.
            • Re: (Score:3, Informative)

              by AxelBoldt ( 1490 )

              when taken in its normal form it requires activation by UV in the skin.
              That is crap. You can either take in D2 (from plants or fungi) or D3 (from animal sources) or you can produce your own D3 from sunlight and cholesterol. All these are converted by the liver into the active from of vitamin D, Calcitriol.
              • Re: (Score:3, Informative)

                by iamplupp ( 728943 )
                Well actually it is converted to 25-OH-vitamin D in the liver. And that in turn gets converted to calcitriol in the kidney.
      • Re: (Score:2, Funny)

        by jonadab ( 583620 )
        > The main source of vitamin D in humans is through exposure to sunlight.

        I'm pretty sure that's not true in my case. In the first place, I drink a lot of milk, which is most likely fortified with vitamin D, and in the second place, my skin is roughly the same color as milk, because I spend 165+ hours a week indoors.
    • Re: (Score:3, Insightful)

      by Detritus ( 11846 )
      You can poison yourself with excessive amounts of vitamin D. Then again, you can poison yourself with almost anything if you try hard enough.
      • Re: (Score:2, Insightful)

        by Gridpoet ( 634171 )
        Yes, you can indeed poison yourself... if you take 75,000IU a day!!!! a 1000IU pill (considered a 250% dosage by the FDA) is about .25 inches long and .15inches in width... you would have to take 75 of these a day to get poisoned... seriously, thats like an entire bottle a day....if your taking that many of the same vitamins you might want to see a psychologist... and a medical doctor to pump your stomach

        i personally take 4000IU a day, due to several reaserch papers i've read pointing to this being a more a
        • by Detritus ( 11846 ) on Sunday April 29, 2007 @07:37AM (#18917987) Homepage
          The Food and Nutrition Board of the Institute of Medicine has set the tolerable upper intake level for adults at 2000 IU. Going higher than that may cause problems.

          http://ods.od.nih.gov/factsheets/vitamind.asp [nih.gov]

          • Re: (Score:3, Insightful)

            by Pharmboy ( 216950 )
            Or just get regular UV exposure and your body will autoregulate itself and you will get exactly what you need: no more, no less. Kinda what nature intended.

            As far as I know, no one has died or gotten sick from an overdose of vitamin D that was generated from UV exposure.
            • by reversible physicist ( 799350 ) on Sunday April 29, 2007 @11:43AM (#18919311)
              The "controversy" about the health benefits of sun exposure is fueled mainly by the tanning industry. All of the large studies on which the health benefit claims are based (including the one cited here) used oral vitamin D, not sun exposure. To quote from the abstract of a recent article in The Journal of steroid biochemistry and molecular biology (B. Gilchrest, March 2007),

              Ultraviolet (UV) radiation is a proven carcinogen, responsible for more than half of all human malignancies. It also compromises skin appearance and function. Since the UV action spectra for DNA damage, skin cancer and Vitamin D(3) (vit D) photosynthesis are identical and vit D is readily available from oral supplements, why has sun protection become controversial, now that some data suggest conventionally "sufficient" levels of vit D may be less than optimal for at least some population groups? First, the media and apparently some researchers are hungry for a new message. Nevertheless, after 50 years, UV exposure is still a major avoidable health hazard. Second, the controversy is fueled by a powerful special interest group: the indoor tanning industry. They target not the frail elderly or inner-city ethnic minorities, groups for whom evidence of vit D insufficiency is strongest, but rather fair-skinned teenagers and young adults, those at highest risk of UV photodamage. Third, evolution does not keep pace with civilization. When nature gave man the appealing capacity for vit D photosynthesis, the expected lifespan was far less than 40 years. Long-term photodamage was not a concern, and vit D was not available at the corner store. The medical community should avoid sensationalism and instead rigorously explore possible cause-and-effect relationships between vit D status and specific diseases while advocating the safest possible means of assuring vit D sufficiency.
    • Re: (Score:3, Insightful)

      Now I'm waiting for another research showing that the intake of vitamin D causes some other serious illness... So typical.

      You are wise to be skeptical of such reports, but unwise if you disregard them completely. Yes, medical history is full of contradictions to previously known nutritional 'facts', and this one may be falsified in time as well. Yet, each case should be considered on its merits, not by some blanket "other research will show the opposite, so let's ignore them all".

      Specifically, this vi

  • by Lord Duran ( 834815 ) on Sunday April 29, 2007 @04:45AM (#18917355)
    60%. That's not a small number. Consider the possibilities: 60% of cancer reduced, just by using a standard vitamin pill. I think I'll head off to the pharmacy.
    • Re: (Score:3, Funny)

      by aussie_a ( 778472 )
      Well the study was only done with women Lord Duran. I don't think dressing up in women's clothing will get you the 60% boost in your cancer avoidance abilities.
    • by mrbluze ( 1034940 ) on Sunday April 29, 2007 @05:34AM (#18917553) Journal

      I think I'll head off to the pharmacy.

      Not so fast ;)

      Vitamin D is a fat soluble vitamin and is present in meat products. Deficiency in Vitamin D causes rickets [wikipedia.org]. Vitamin D is so-called, and many would think it was not available without a dietary source, but it is produced in the skin under the influence of UV light. It then gets processed by the liver, then 'activated' in the kidneys and off it goes and does good things.

      Because it is fat soluble, it is unlike Vitamin C in that stores are steady and no Vitamin D production only starts to cause problems after several months.

      Whilst Vitamin D requirements increase with age, sun exposure commonly decreases with age, especially in the elderly. Much of this is simply a lifestyle issue.

      Importantly, Vitamin D is already known to have immunomodulatory activities (a well functioning immune system is critical in preventing cancer over time). It is also known to induce some cancers to self-destruct.

      • by Splab ( 574204 )
        So we should get fatter and stay in the sun longer?

        Guess mortality rate will stay at same levels then ;)
        • So we should get fatter and stay in the sun longer?

          Actually, not as stupid as it sounds. At least then you'd be happier. It has been shown that decreased serum lipids predispose people to depression and suicide. Depression and stress itself promotes cancer. I guess if we managed to farm fish a bit more efficiently, it would really be something to think about. Problem though is, the fatso's you see in the street aren't eating too much fish, but too much MacDonald's which is practically devoid of any nutrients, as far as I can tell.

      • by RonBurk ( 543988 ) on Sunday April 29, 2007 @01:59PM (#18920141) Homepage Journal

        gets processed by the liver, then 'activated' in the kidneys and off it goes and does good things.

        Well, you're only about 10 years behind the research with that description, which puts you even with most doctors. The revolution in Vitamin D research came with the discovery that D is "activated" (25OH-D3 turns into 1,25OH-D3) in a variety of different tissues of the body, not just the kidneys.

        Which body tissues do we know can "activate" Vitamin D3? Here's some: prostate tissue, colon tissue, breast tissue. Where are some popular places that cancer likes to form? Same list. Hmmm.

        no Vitamin D production only starts to cause problems after several months.

        You might be right, but I'm betting not. Here, things get interesting.

        In general, significant (not the 200IU your doctor will tell you to take) levels of Vitamin D3 pretty much always correlate with "better outcome" when it comes to cancer. Even folks with skin cancer who have higher levels of D3 do better than folks who don't. But, there are a few puzzling instances where studies find a U-shaped curve. In other words, they find some instances where people with medium levels of Vitamin D3 do better than those with low -- but those with high levels of Vitamin D3 do as bad as those with low levels! What explains these contradictions?

        There is a simple hypothesis (far from proved, but I'll bet my pill taking regimen on it for now) that explains this: local tissue conversion of 25OH-D3 to 1,25OH-D3 shuts down as soon as serum levels of 25OH-D3 start to decline, and doesn't start up again until serum levels stabilize.

        If this hypothesis is true, then allowing your vitamin D3 serum levels to drop during the winter may be as bad for you as just having low levels of vitamin D3 all year round.

  • by mshurpik ( 198339 ) on Sunday April 29, 2007 @04:54AM (#18917389)
    TFA: >Referring to Linus Pauling, the famous U.S. advocate of vitamin C use as a cure for many illnesses, he said: "Basically, Linus Pauling was right, but he was off by one letter."

    OK, who else had the feeling that they were going to bash vitamin C before the end of the article?
  • by mavi_yelken ( 801565 ) on Sunday April 29, 2007 @04:54AM (#18917393)
    Get naked and get out! you know.. for Vitamin D synthesis.
    • by Dogtanian ( 588974 ) on Sunday April 29, 2007 @06:04AM (#18917637) Homepage

      Get naked and get out! you know.. for Vitamin D synthesis.
      The prospect of the Slashdot readership (overweight or skinny nerds) running about the streets naked, exposing their skin to the sun for the first time in years does not appeal to me. :-6

      In fact, the sun reflecting off all that pasty-white flesh is likely to blind many people and cause traffic accidents.
  • by aschoff_nodule ( 890870 ) on Sunday April 29, 2007 @05:22AM (#18917515)
    I believe that Vitamin D might protect against some cancers.

    However, I do not agree that Vitamin D deficiency can be responsible for about 60% cancers.

    Here are my reasons why:

    1) The process of carcinogenesis (initiation of the first DNA mutation/ adduct required to form cancer to the stage of clinically overt disease) in most cases takes more than 4 years. This clinical trial is only 4 years and too premature to reach to conclusions.

    2) I have yet to read the paper, but it is necessary to know whether this trial was truly randomized meaning that the those who got the Vitamin D pill and those who got the placebo were similar to each other in all other ways. It is possible that if it is not randomized, a healthier cohort of people chose to take Vitamin D for a long time.

    3) It is also important to know how they treated those people who dropped out of taking the Vitamin D pills. It is possible that unhealthier people dropped out and then we were comparing all subjects in the placebo group to the "healthier" people in the Vitamin D group.

    4) A risk reduction of 60% (= relative risk of 0.4) is epidemiologically very strong and if that was the case, we would have already found such a role of Vitamin D much earlier (like 30 years before or so). There is something called Bradford Hill's criteria for causation in epidemiology which has strength of association as one of the criteria. The rationale for that is if we had a confounder which is actually responsible for the effect, we would have known it before because it is more likely to have a stronger effect. The same principle goes here. We do not know anything that could prevents so many types of cancer with such great attributable fraction. The magnitude of effects of like 2.5 or reduction of risk to 0.4 were the strengths we used to see in the papers of 1970s. Hence I think there could be some issues with the study design and data analysis of this study if they found such a great magnitude of effect.

    Having said that I think that Vitamin D might prevent many cancers, but I expect a lower magnitude of the effect.

       
    • by knapper_tech ( 813569 ) on Sunday April 29, 2007 @06:03AM (#18917627)
      You have yet to read the paper, but you do not agree that Vitamin D deficiency can be responsible for 60% of about cancers. Congratulations. You have a lifetime supply of straw man ashes.

      All you did was list reasons why you're skeptical of the results, yet you haven't read the paper. Granted they are plausible reasons, someone who is capable of excercising this kind of critique could do the world a favor by reading the article to either confirm or address their skepticism and then posting their final interpretation of the article.

      This post is like reading intial lab notes. I don't care what you're hunch is now if you can follow through on the data (do several hundred more experiments in the lab) and come to something more conclusive. The paper isn't a state secret. Read it.
      • The paper isn't a state secret. Read it.

        Did you see a link to a paper? I'd like to read it, but couldn't find one. Am I blind?
    • by adrianmonk ( 890071 ) on Sunday April 29, 2007 @10:33AM (#18918889)

      4) A risk reduction of 60% (= relative risk of 0.4) is epidemiologically very strong and if that was the case, we would have already found such a role of Vitamin D much earlier (like 30 years before or so). There is something called Bradford Hill's criteria for causation in epidemiology which has strength of association as one of the criteria. The rationale for that is if we had a confounder which is actually responsible for the effect, we would have known it before because it is more likely to have a stronger effect. The same principle goes here. We do not know anything that could prevents so many types of cancer with such great attributable fraction. The magnitude of effects of like 2.5 or reduction of risk to 0.4 were the strengths we used to see in the papers of 1970s.

      I see where you're going with that. The more obvious things tend to be the ones discovered first. It's not a hard and fast rule because it's quite possible for everyone to miss something obvious for a long time (due to groupthink or just chance), but it is a good rule of thumb.

      On the other hand, there's another possible explanation for why this was not discovered in the 1970's when all the other big factors were being discovered: if a variable doesn't change much, it's harder to notice what happens when it does change. The push to wear high-SPF sunscreen didn't occur until after the 1970's and neither did the warnings to stay out of the sun. So it seems possible that the reason this phenomenon wasn't discovered in the 1970's was that it didn't exist in the 1970's. I'm not saying that the (supposed) causal link between vitamin D deficiency and cancer didn't exist; what I am saying is that vitamin D deficiency may have been uncommon enough that the causal link didn't matter because it wasn't being "triggered".

      Of course, I'm postulating something about how common vitamin D deficiency is now versus 30-ish years ago, and I don't really have any data to say that difference actually exists, so my whole argument may be BS. Not only that, vitamin D deficiency would have to have been rare enough not just to be uncommon but to actually reduce the effects down near the noise level.

  • Is it normal to be concerned that TFA doesn't appear to mention where the funding for this research came from?
    • Re: (Score:2, Funny)

      by Anonymous Coward
      Yeah, I bet you it was the freakin' SUN, that Sun is always trying to sucker people into getting outdoors.
  • by MavEtJu ( 241979 ) <<gro.ujtevam> <ta> <todhsals>> on Sunday April 29, 2007 @05:47AM (#18917587) Homepage
    Let me see... People roll from their bed into their car (via a door between the house and the garage), drive to work and park under the building. Lunch in the canteen, and in the evening the same path and sitting in front of the TV. 90% of the people in the apartment block I'm living in does live this way and get no direct sunlight for weeks. I think I found the reason why people have a vitamin D deficiency!
  • It took me about 20minutes of reading to confirm that living abroad has left some holes in my diet, and because of the mechanisms of vitamin D mentioned in the article, I've decided I need to pay a lot more attention to the local diet.

    When I lived in the states, I was in Oklahoma and probably ate two or three bowls of cereal a day. Lots of milk. I am a cereal fanatic. As far as getting my vitamin d intake up, all the cereal coupled with the rest of the food I ate, the sunlight in Oklahoma, and being a
    • by am 2k ( 217885 )

      According to this page [bchealthguide.org], rice and soy are also good sources, which should be easy to get in Asian countries.

  • Really Bad Taste (Score:3, Insightful)

    by zappepcs ( 820751 ) on Sunday April 29, 2007 @06:15AM (#18917671) Journal
    Okay, how long before we see:

    Cancer patients in the hospital doing "Got Milk?" public service announcements?

    Nudist colonies advertising the health benefits of their lifestyle?

    Advertisements for anti-cancer tanning beds?

    Some research paper by two male med students doing a paper on cancer in nudist lifestylers?

    Spam email selling vitamin D pills at only twice the cost of c14li5? sponsored by 3400 people in the US and Russia

    Advertisements for GM milk that has twice the cancer curative properties of normal milk? sponsored by Monsanto

    A study linking cancer and baby formula vs. mother's milk? sponsored by Gerber

    Research that shows the George Forman iGrill retains more vitamin D than any other meat preparation method?

    ok.... I'm going to stop now
    • by grumling ( 94709 )
      Don't forget spam...

      "Our growth supplements have more vitamin D than anyone else's, so you can achieve a thicker, fuller member and be confident that you'll not have to worry about cancer."
  • by giafly ( 926567 ) on Sunday April 29, 2007 @06:21AM (#18917695)

    Only brief full-body exposures to bright summer sunshine -- of 10 or 15 minutes a day -- are needed to make high amounts of the vitamin. But most authorities, including Health Canada, have urged a total avoidance of strong sunlight or, alternatively, heavy use of sunscreen. Both recommendations will block almost all vitamin D synthesis.

    Those studying the vitamin say the hide-from-sunlight advice has amounted to the health equivalent of a foolish poker trade. Anyone practising sun avoidance has traded the benefit of a reduced risk of skin cancer -- which is easy to detect and treat and seldom fatal -- for an increased risk of the scary, high-body-count cancers, such as breast, prostate and colon, that appear linked to vitamin D shortages [my highlights].

    The sun advice has been misguided information "of just breathtaking proportions," said John Cannell, head of the Vitamin D Council, a non-profit, California-based organization.
    Our modern diet is very different from what we evolved to eat. Better in some ways - few Westerners starve - but probably lower in many micronutrients [wikipedia.org] than the ideal. So this type of report is not a surprise. Expect more.
    • by AmiAthena ( 798358 ) on Sunday April 29, 2007 @07:21AM (#18917907) Homepage

      Our modern diet is very different from what we evolved to eat. Better in some ways - few Westerners starve - but probably lower in many micronutrients than the ideal. So this type of report is not a surprise. Expect more.
      QFT... the evolution of our dietary needs is exactly why so many of us do have weight issues. Everyone who's ever went on a diet or tried to eat healthier has one major complaint: all the stuff that tastes good is bad for you. But there's a reason for that! Cavemen didn't have Twinkies, Haagen-Dazs, and Big Macs. Protein, fat, and sugar/carbs were necessities to the developing human, and they were pretty scarce. Early man had green leafy stuff to eat as far as the eye could see, but it was work to kill something for food. So we evolved to have a greater affinity for these rare essentials.

      Up until one or maybe two hundred years ago, this worked fine. Only the wealthy could afford to gorge themselves to dangerous levels of obesity. Today, for maybe $6, I can go to Burger King and get a Whopper, fries (King Size) and a Coke (King Size). According to BK's own meal-builder nutrition info, this meal has 1660 calories (650 from fat), 72 grams of fat, and 117g total sugars. And I didn't even put cheese on that Whopper. (And no Vitamin D as far as I can tell.) This is theoretically one out of three meals, supposedly totaling 2000 calories. In all likelihood, it's more like hald the day's calories than most. Meanwhile, the average modern American doesn't burn nearly as many calories Mr. Caveman did, since we survive by sitting in cubicles instead of hunting and gathering. Clearly, our ability to feed ourselves has improved to the point where the foods we naturally crave due to things coded in our genes thousands of years ago are actually harming us. For all the exotic things we can now eat because of technology, our range of nutrients sucks.

      So it's hard to diet because as far as your body knows, that triple fudge brownie might be the the calories you burn not freezing to death tonight. And since you're body's so preoccupied with this now baseless fear of starvation, it forgets to make you want to eat things like broccoli or spinach, which our ancestors were probably eating to pass the time until some meat wandered close enough to kill. Call it evolutionary sabotage- what we needed before is not what we need now, and if we can't stay on top of those changes, we tend to die.
  • People have been going much more to the beach in the last half-century than before. Even people in Nordic countries have been going to tropical countries during their vacations. People have been exposing more skin.


    Do the epidemiological studies report a large drop in cancer starting about 50 years ago? Particularly in northern countries?


    If vitamin D has any effect in cancer, these factors should stand out clearly.

  • by Eggplant62 ( 120514 ) on Sunday April 29, 2007 @06:49AM (#18917797)
    The doctor that I work for has asked me to research this very line of thinking for her, pulling every article out I could find on multiple sclerosis (MS) and Vitamin D, and I even ended up using some of that research in a paper I wrote for an English class.

    There's a very significant link between Vitamin D deficiency and MS. Most MS cases occur in the far north and far south climes. Think of southern Australia and Tasmania and northern Europe and United States, areas where sunshine is at low levels for as much as nine to ten months out of the year. We are able to make Vitamin D via sun exposure on the skin, which for humans, is a primary source of Vitamin D. Some of these studies find that people who had high levels of sun exposure as children greatly reduces their risk of contracting MS.

    Don't believe me? Read these studies. There are tons more just like them, confirming the suspicion.

    • Re: (Score:3, Informative)

      by solanum ( 80810 )

      Think of southern Australia and Tasmania... ...where sunshine is at low levels for as much as nine to ten months out of the year.

      You are joking, southern Australia gets huge amounts of sunlight thus it has the one of the worlds highest rates of skin cancer. Don't forget that the latitude of the south coast of Australia is only about 36 degrees and that the southern hemisphere receives more sunlight than the northern hemisphere due to the eccentricity in the earth's orbit (and angle of axis). Most people in southern Australia have difficulty getting enough sunscreen on year round rather than getting enough sun exposure.

    • Re: (Score:3, Interesting)

      by scottv67 ( 731709 )
      northern Europe and United States, areas where sunshine is at low levels for as much as nine to ten months out of the year.

      Dude, I live in Wisconsin (there is just a weee little sliver of Michigan between WI and Canada) and it's not as light-deprived as you make things sound. Do you think we scurry around in the dark with flashlights like mole-people (except for June and July)?

      Interesting sidebar: I was in Philadelphia recently on a work-related trip. On the way to the airport, the Philly cabbie ask
  • I am suspicious. (Score:5, Interesting)

    by Killshot ( 724273 ) on Sunday April 29, 2007 @07:02AM (#18917853) Homepage
    Did you notice the link in the article to the vitamin D council?
    Did you notice the doctor who did the study is part of the vitamin D council?
    Although they are a non profit, they do provide links to lots of people who will be happy to sell you some vitamin D.

    I work for a small biotech company that has been doing cancer research and we never put out a press release every time we think we are on to something interesting or promising. We do study after study not just to establish a link, but to understand exactly how a compound may stop or prevent cancer.
    I wish people would take more time to ensure they have lots of data to go on before saying they have found a "direct link"

    And on another note, I find it hard to believe that so many people are deficient in vitamin D.
    We may spend a lot more time indoors than our ancestors, but I feel confident I am getting enough sunlight and enough D in foods i consume.
    • by awfar ( 211405 )
      If it was anything other than Vitamin D, I would be as concerned with the conflict of interest as well. But Vitamin D is sprayed(I think) by the gallons on cereal and there cannot possibly be a huge, terribly lucrative market to be leveraged when the cheap solution is to go outside or bathe yourself in a sunlamp.
    • Vitamin D3 (the good version) costs about 2c - 5c per 1000 IU tablet (2.5x RDA) at places like Costco, Swansons, Puritans Pride, Sams Club, Walmart etc depending on size bottle and frequent specials. Huge obscence profits, conspiracy to take over the world (sarcasm). However in northern latitudes like Canada, Alaska, Scandinavia, northern Russia, these are very basic health issues worked in a number of mainstream North Am medical schools despite rampant anti-vitamin politics. Score one for the med school
    • The "conflict of interest" doesn't bother me, but the lack of a link to or citation of a published study does. Does anyone know where the real details about this study are available?
      • The "conflict of interest" doesn't bother me, but the lack of a link to or citation of a published study does. Does anyone know where the real details about this study are available?

        They're not. That's the problem, he's talking to a newspaper without having published anything. AFA I can tell from the article, he hasn't even presented his results as an abstract or a talk at a meeting. And the Globe & Mail is usually pretty good on reporting medicine, but this story doesn't even mention whether it's a prospective, randomized controlled study or a retrospective, backwards-looking study. (And it doesn't get a reacton from another scientist who knows the research.) Apparently it's a

  • Sunlight exposure before the age of 16 has also been linked to occurence of Multiple Sclerosis. It's not clear whether this is because of Vitamin D production/regulation though.
  • by DrNickDonovan ( 1056132 ) on Sunday April 29, 2007 @08:08AM (#18918113)
    It's interesting to note that regardless of the type of cancer (save some of the forms of mesothelioma that you tie to chemical exposure) the majority of cancers can be traced back to oxidative stress. As a physician I've seen remarkable results with dropping the usual chemical approach and using super antioxidents such as Acai extracts and grape-seed extracts.) My fellow physicians need to get off of the chemical bandwagon and really do some research in this direction. Cheers, Nick
  • by Spittoon ( 64395 ) on Sunday April 29, 2007 @09:36AM (#18918565) Homepage
    The arrogance in the comments to this article is pretty astonishing. Either you don't believe the study because apparently you're an expert, or you think you're already getting enough Vitamin D and don't need to pay attention to it.

    You'd think the study was telling us that battery acid cures cancer, rather than some natural substance that everybody agrees is necessary to live.

    So what if milk producers funded the study-- they did some work, it seems legit, and they're advocating a substance we NEED TO LIVE ANYWAY, and which could POSSIBLY KEEP YOU FROM GETTING CANCER.

    Protect yourself. Read the wikipedia article:
    http://en.wikipedia.org/wiki/Vitamin_D [wikipedia.org]

    Add fish oil and yogurt to your diet, and then, my dear geeky friend, take your ass outside for just a little bit each day. Walk around the block or something. It won't hurt you unless you get hit by a bus, and it MIGHT KEEP YOU FROM GETTING CANCER.
  • It's not enough. (Score:5, Interesting)

    by ScrewMaster ( 602015 ) on Sunday April 29, 2007 @11:07AM (#18919101)
    As an American I can only say this: focusing on Vitamin D (or any other single nutrient) as a factor in causing disease X or condition Y simply shifts our attention from the real problem. And that is the simple, undeniable, thoroughly-established fact that our diet sucks. Sucks on a Biblical scale. If more of us accepted that and made some (admittedly significant) changes to that dietary intake, there'd be one hell of a lot fewer people with cancers of any kind. Not to mention strokes, and heart attacks, and diabetes, and all of the other diet and obesity-related conditions from which we suffer. My mind is absolutely boggled by the sheer scale of health problems resulting from typical American fare, and I feel sorry for people in other countries that are adopting American food because they think it's better for them. Chances are, compared to their traditional diet ... it isn't.

    For example, my fiancee is North African, and her traditional meals are largely vegetarian with relatively few percent of calories from animal-derived foods. She's never had a health problem. Her grandmother is 103. Granted, the reason the average person from her country doesn't eat more meat is because they can't afford it, not because they have some inhibition about eating meat. Yet, the wealthier members of the population there are eating more and more American-style foods and guess what ... they're already seeing an increase in cancers, strokes, heart attacks and diabetes, but without the drugs and surgical techniques we use to try and compensate for the lifetime abuse of our bodies.

    Don't get me wrong: I'm glad they're researching the effects of insufficient Vitamin D reserves on cancer. We can just add that into our total body of knowledge about diet and health. But we really need to keep our minds on the big picture, which clearly says that we don't eat right. Too many people I know have suffered or died from what they ate over their shortened lifetimes. So here I am, now at the age where I have to take a good, hard look at my family history, and take stock of my future health. The conclusion I've reached is this: either I make some serious changes to what I eat, and the way I live ... or the outlook will not be good. So, I'm making those changes.

    My father died of diabetic complications at the age of 62, and his doctor said to me "that's one possible future for you." It was an awful, painful, degenerative death that lasted several years. I don't want to go that way, and sometimes we have to accept that changing a few little things here and there aren't going to cut it. Taking some Vitamin D supplements, or getting some more Sun, or eating some more broccoli ... that's fine so far as it goes. It doesn't go far enough for most of us. Not nearly far enough.
  • by TheMohel ( 143568 ) on Sunday April 29, 2007 @11:21AM (#18919171) Homepage
    Okay, after reading the entire hysterical FA, I want that ten minutes of my life back. A sensationalistic article published on a slow-news Sunday in the Globe and Mail (where I always look for good peer-reviewed scientific evidence) says that a study "will be published" in June that will revolutionize the way that I, a practicing physician, view chronic disease.

    Or maybe not. I can't tell whether the study was prospective, controlled, or blinded. I can't tell what cancers were examined. I CAN tell you that four years is ridiculously short for a study examining the emergence of cancer, which appears (we're not sure yet) to take decades in most cases. Since the journal is not named, I don't know its reputation or whether the study was peer-reviewed (and by what peers). In other words, I have no information that allows me to evaluate the claim, except that the claim itself was published in the newspaper. This in itself is not a good sign.

    It is a violation of scientific ethics to pre-announce your results in the lay press without also revealing the details of your methods and the limitations of your study. In the case of a "miracle" result for a common supplement, it rises to the level of being truly suspicious. Extraordinary claims really do require extraordinary proof, and making such a claim in a Sunday supplement in the complete absence of accompanying evidence is the stuff of psychics and snake oil.

    I am skeptical. I am willing to be convinced, but I'm also willing to entertain cash bets on the probability of this being true and clinically useful.
  • by Somnus ( 46089 ) on Sunday April 29, 2007 @02:38PM (#18920447)
    I have Vitamin D deficiency [wikipedia.org], and it came close to ruining my life. I am a scientist, but I also have dark skin that never burns. Even though I don't own a car, I just can't get the 2-3 hours of sunshine daily needed to fulfill my Vitamin D requirement; white folks only need 20 minutes. Moreover, it's kind of chilly where I live, so I wear long pants and sleeves much of the time.

    Over time, I developed a pain that just sucked the life out of me -- like I was playing four quarters of football daily, with the flu. Even with powerful pain killers I couldn't sleep, and woke up every day feeling I was hit by a bus.

    The link to cancer is still an open question, but the pain is a hard fact [mayoclinic...edings.com].

    PS: The only way to overdose on Vitamin D is to abuse prescription-strength supplements or cod liver oil.

Keep up the good work! But please don't ask me to help.

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