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  4. vitamin suppliments
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vitamin suppliments

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paul.fr

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vitamin suppliments
« on: 27/03/2007 07:21:45 »
do we actually need vitamin suppliments? you see in boots for instance, a whole range of suppliments with a lot aimed at children.

do children need suppliments?

I can see a case for them in more deprived countries where a balanced diet may not be possible.
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another_someone

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vitamin suppliments
« Reply #1 on: 27/03/2007 08:07:42 »
Vitamins are substances that we require in very small doses, and many of them are definitely toxic if overdosed.  Overdoses with vitamin A and iron (although iron is not technically a vitamin, but often bundled in with over the counter supplements) can certainly cause serious health problems, whereas water soluble vitamins, such as vitamin C, have much wider tolerances to overdose.

If you are short on a vitamin, you should top up to make up for the shortfall, but if you are not sufferring from a shortfall, then you should regard vitamin tablets with caution.

There have actually been some reports of negative correlation between vitamin supplemets and good health.

http://www.thenakedscientists.com/forum/index.php?topic=6661.0

Although you will see that the report is not without controversy.
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paul.fr

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  • vitamin suppliments
    « Reply #2 on: 27/03/2007 09:42:54 »
    Quote from: another_someone on 27/03/2007 08:07:42
    If you are short on a vitamin, you should top up to make up for the shortfall, but if you are not sufferring from a shortfall, then you should regard vitamin tablets with caution.
    Although you will see that the report is not without controversy.

    This was my thinking, George.

    so why do they advertise vitamins for children? in nice colourful packaging, shaped like sweets and animals with wording that could make a parent think their child should be taking them?
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    Offline iko

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    vitamin suppliments
    « Reply #3 on: 27/03/2007 18:56:17 »
    Quote from: paul.fr on 27/03/2007 07:21:45
    do we actually need vitamin suppliments? you see in boots for instance, a whole range of suppliments with a lot aimed at children.

    do children need suppliments?

    I can see a case for them in more deprived countries where a balanced diet may not be possible.

    Hi paul.fr,

    It is just a matter of knowledge, culture, information or family tradition if you like.
    We may not be what we eat, but certainly we have to eat to survive, even if we tend not to live only to eat, fortunately.
    If the combination of foodstuff we eat from time to time is correct, thanks to our family traditions and culture, for example, we probably won't have any deficiency problem from the cradle to the end of our life.  Even if we have to face a period of starvation or a polar expedition, our information, culture, tradition will help.
    Over the years, many children had to be reminded: have your orange juice plus scrambled eggs, get your fresh veggies each meal, eat fruits, drink your milk and go play outside, take your 'cod'...
    Ignoring the basic principles of our survival on this Planet might lead to dreadful consequences.
    At least one young man became irreversibly blind for a badly managed diet.
    Here is the story:

    Blindness in a Strict Vegan

    Vegetarians are at risk for nutritional deficiency if they do not receive vitamin supplementation. We report a case of severe bilateral optic neuropathy in a patient who had been a vegan for many years and who did not take vitamin supplements.
    The patient, a 33-year-old man who had started a strict vegetarian diet at the age of 20 years, was referred for evaluation of progressive visual loss. "Improved health" was the reason for the diet, which contained no eggs, dairy products, fish, or other sources of animal proteins. He did not smoke or use alcohol, and his medical history was unremarkable.

    Examination showed severe bilateral optic neuropathy with very poor vision (less than 20/400 in both eyes), central scotomata, dyschromatopsia, and atrophy of the optic disks. We found no evidence of a compression of the visual pathway or of a toxic, infectious, or inflammatory cause of the blindness. Mitochondrial-DNA analysis showed no mutation for Leber's hereditary optic neuropathy. On neurologic examination, there was a sensory peripheral neuropathy, confirmed by electrophysiologic studies. The cerebrospinal fluid was normal, including the opening pressure. The remainder of the general examination showed no abnormalities.

    The plasma level of folate was low (5.4 nmol per liter; normal range, 7.5 to 28), as were the levels of vitamin B1 (4 nmol per liter; normal range, 6 to 40) and vitamin B12 (114 pmol per liter; normal range, 150 to 720). There were also deficiencies of vitamins A, C, D, and E and zinc and selenium, but plasma levels of iron, ferritin, vitamin B6, and nicotinamide were normal. The patient had megaloblastic anemia (hemoglobin level, 10.5 g per liter; mean corpuscular volume, 110 µm3), which was not due to pernicious anemia (there were no anti–parietal-cell or anti–intrinsic-factor antibodies, upper gastrointestinal endoscopy showed normal findings, and multiple biopsies showed no gastric atrophy) or other causes of malabsorption. After treatment with intramuscular vitamin B12 (1000 µg daily for one week) and oral multivitamin supplementation, the hemoglobin level was normal and the sensory neuropathy had disappeared, but there was no recovery of vision.

    Vitamin B12 deficiency in vegetarians may cause neurologic disturbances.  Moreover, deficiencies of vitamins B12 and B1 may be responsible for optic neuropathy associated with nutritional factors.   Amblyopia and painful neuropathy have been reported in cases of dietary deprivation in prisoners during World War II, and more recently, dietary factors were noted in the Cuban epidemic of optic neuropathy.4 The optic neuropathy in our patient was apparently related to deficiencies of vitamins B12 and B1, but other associated deficiencies may have had a role. Vitamin supplementation is essential in persons who adhere to a strict vegetarian diet, especially because vitamin deficiencies may cause severe, irreversible optic neuropathy.


    Dan Milea, M.D.
    Nathalie Cassoux, M.D.
    Phuc LeHoang, M.D., Ph.D.
    Groupe Hospitalier Pitié–Salpêtrière
    75651 Paris CEDEX 13, France

    New England Journal of Medicine  342:897-898  March 23, 2000.
    « Last Edit: 18/04/2009 16:13:35 by iko »
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    another_someone

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    vitamin suppliments
    « Reply #4 on: 27/03/2007 22:21:27 »
    Quote from: paul.fr on 27/03/2007 09:42:54
    so why do they advertise vitamins for children? in nice colourful packaging, shaped like sweets and animals with wording that could make a parent think their child should be taking them?

    Would you trust a salesman for medical advice?
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    paul.fr

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    vitamin suppliments
    « Reply #5 on: 28/03/2007 01:00:19 »
    Quote from: another_someone on 27/03/2007 22:21:27

    Would you trust a salesman for medical advice?

    personally, no. But the way they are marketed at some stores i feel sure some parents do. like i said the way they are packaged and come in inviting shapes and colours, they "appear" to be aimed at children.

    on the other hand do you trust your doctor to give you the best medication for your ailment/illness. what if he had recently been visited by a friendly female drug company sales rep with nice legs and a low cut top, who bought some nice stationary, pizza, etc and by chance happened to be reccomending her employers drug as opposed to the one the doctors practice usually dispenced.

    is that drug more effective than the one your doctor used to prescribe, does it compare cost wise, are there inducements going to the doctor or his practice to change drugs and drug supplier?

    are you not then getting medical advice from a salesman?
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    paul.fr

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    vitamin suppliments
    « Reply #6 on: 28/03/2007 01:09:23 »
    Quote from: iko on 27/03/2007 18:56:17
    Hi paul.fr,

    It is just a matter of knowledge, culture, information or family tradition if you like........

    Hello, Iko.

    thanks for the info, i understand what you are saying. I just think the way suppliments and multi vitamins are marketed (in the UK) may make people think they need to take them even if they do not.

    there are always offers on, buy one get one free, three for the prioce of two, i feel sure people buy the extra ones thinking they need then and wow they are also at a bargain price.
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    Offline Karen W.

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    vitamin suppliments
    « Reply #7 on: 28/03/2007 03:46:45 »
    Well my children never took vitamins because they were pretty well rounded in their choice of diets . I take care of many children who would benefit from a supplement as they don't eat properly. Some children and parents do not know about good nutrition and do not make sure their child is eating properly. Not out of neglect but ignorance about nutrition. Then you have children with parents who struggle to get their finicky eaters to eat and they only pick, and are always naturally skin and bone, to a point it looks unhealthy, these parents take wonderful care of their children and have regular doctor visits to monitor their child's eating and weight. The vitamins can be good for children especially those who won't eat fruit vegetable or meat. Perhaps all they want is bread .. these children end up needing extra supplements and attention from doctors and parents to insure they remain healthy because let me tell you! I have seen some extremely picky children hungry all the time as they only want empty calories and in no time are starving again.. I think a doctor is always a good idea to consult before administering vitamins weather they are over the counter or not!
    « Last Edit: 28/03/2007 03:50:02 by Karen W. »
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    another_someone

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    vitamin suppliments
    « Reply #8 on: 28/03/2007 05:28:14 »
    Quote from: paul.fr on 28/03/2007 01:00:19
    on the other hand do you trust your doctor to give you the best medication for your ailment/illness. what if he had recently been visited by a friendly female drug company sales rep with nice legs and a low cut top, who bought some nice stationary, pizza, etc and by chance happened to be reccomending her employers drug as opposed to the one the doctors practice usually dispenced.

    is that drug more effective than the one your doctor used to prescribe, does it compare cost wise, are there inducements going to the doctor or his practice to change drugs and drug supplier?

    are you not then getting medical advice from a salesman?

    I would worry at least as much about political interference with the medical profession.

    But, yes, there is a great deal of interference from all sides in medical advice.  A goos doctor is meant to provide a buffer between the sales pitch and the patient, but ofcourse, not all doctors are equally good.
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    paul.fr

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    vitamin suppliments
    « Reply #9 on: 28/03/2007 06:38:59 »
    too true, George.
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    Offline GBSB

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    vitamin suppliments
    « Reply #10 on: 28/03/2007 15:38:36 »
    Quote from: paul.fr on 28/03/2007 01:00:19

     what if he had recently been visited by a friendly female drug company sales rep with nice legs and a low cut top, who bought some nice stationary, pizza, etc a

    I know what you mean paul.fr.
    It happens to me every day. And I am not even a doctor. [;D]



    Ahaaa! That’s explaining everything. (Klaus Kinski as Doctor Zuckerbrot-in “Buddy Buddy”)

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    paul.fr

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    vitamin suppliments
    « Reply #11 on: 28/03/2007 18:55:24 »
    Quote from: GBSB on 28/03/2007 15:38:36
    Quote from: paul.fr on 28/03/2007 01:00:19

     what if he had recently been visited by a friendly female drug company sales rep with nice legs and a low cut top, who bought some nice stationary, pizza, etc a

    I know what you mean paul.fr.
    It happens to me every day. And I am not even a doctor. [;D]



    Ahaaa! That’s explaining everything. (Klaus Kinski as Doctor Zuckerbrot-in “Buddy Buddy”)



    yes, those "big issue" sellers realy know how to generate custom!
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    Offline iko

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    vitamin suppliments
    « Reply #12 on: 28/03/2007 22:47:16 »
    Quote
    there are always offers on, buy one get one free, three for the prioce of two, i feel sure people buy the extra ones thinking they need then and wow they are also at a bargain price.
    paul.fr

    Let's forget about marketing for a minute...it is certainly a minor problem ( [;D])

    When would you buy a good brand multivitamin for your child?

    I think I would when he refuses to eat properly or is not eating at all after a flu or is actually burning so much food doing competitive athletics, gymn, swimming and her/his diet cannot be controlled properly.
    And still I would only think that I am doing my best to support a child's growth and health, just a bit of help as far as I know.

    When would you give cod liver oil to your child?

    This is another story.  We should start giving 'cod' to pregnant and breastfeeding women to have more clever children, if those amazing Nowegian data had been confirmed...and after that?
    I would recommend it as a nutritional support for kids who cannot tan properly in the fall/winter seasons, in those months with the 'r' (from Sept. to April) when we live in a northern country. But this is a much longer story as all of you know.

    http://www.thenakedscientists.com/forum/index.php?topic=4987.0

    Generally speaking, knowing that many people tend to have the strangest diets, is it better to let everybody have a multivitamin each day (they pay for it!) or tell them not to, then wait and see if anybody develops a specific deficiency that most of the times is diagnosed late or never?

    This discussion will go on for ages.

    ikod

    P.S.  Sorry, I almost forgot that we actually live on the Planet Earth.
    Most of the kids suffer from starvation here: they are craving for cofactors and vitamins that could make the difference between life and death (e.g. Vitamin A and zinc for malaria).
    « Last Edit: 02/11/2007 17:46:39 by iko »
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    another_someone

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    vitamin suppliments
    « Reply #13 on: 29/03/2007 01:03:20 »
    http://www.feinberg.northwestern.edu/nutrition/factsheets/copper.html
    Quote
    Although severe copper deficiency is rarely observed, marginal copper status is not uncommon. High dose supplements of zinc, vitamin C, and iron are contributing causes of marginal copper deficiency. Microcytic hypochromic anemia in the presence of normal serum ferritin is the primary clinical feature of marginal copper deficiency. This anemia, which is hematologically identical to iron-deficiency anemia, develops as a result of abnormalities in iron utilization. Skeletal abnormalities, reproductive difficulties, impaired nervous tissue function, and changes in hair and skin pigmentation have been observed in severe copper deficiency. A role for copper in the maintenance of bone mass has been determined from observations of osteoporosis in preterm infants born with inadequate copper reserves.
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    Offline iko

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    vitamin suppliments
    « Reply #14 on: 29/03/2007 18:17:21 »
    Quote
    High dose supplements of zinc, vitamin C, and iron are contributing causes of marginal copper deficiency

    Hi George,
    I think we are talking about moderate/normal dose supplements that, at worst lead to vitamin enrichment of our urine.  No megadoses, we already discussed that in the case of vitamin D from cod liver oil: a little bit may do a miracle, a bit more may be dangerous in many cases.

    As I mentioned in a previous vitamin topic, putting together all the vitamins and minerals as 'supplements' or 'anti-oxidants' is too vague and leads to confusion and no conclusive result, even in a discussion.
    We should  try to be more specific.
    Quality of available products could be a matter of concern: I cited somewhere (cod topic?) the recent finding that the cheaper veggie-derived vitamin D2 is 25% effective compared with the more expensive vitamin D3.  They had been considered equivalent for decades!  The lack of results in preventing fall-fractures in the elderly led to this great 'discovery'...but the initial conclusions where that vitamin D was useless as a whole.
    I was very disappointed then, having given 'cod' for years to my mum to prevent osteoporosis! Now everything is sound again and hopefully she is doing fine not only for a 'placebo' effect.

    ikod
    « Last Edit: 08/05/2007 13:56:05 by iko »
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    another_someone

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    « Reply #15 on: 29/03/2007 19:07:52 »
    The point I was trying to make was that what we need is the right balance.  Potassium and sodium need to be in balance, so unless you know which you have too much of and which you have too little, you don't know which to reduce and which to increase.  The same is for iron/zinc/copper/vitamin C - unless you know which you are short of, you could end up exacerbating an existing imbalance.

    The problem is that the present tendency is just to pile stuff on, without thinking about whether it draws you closer or away from a position of balance.

    I accept that the body is actually quite tolerant to quite a wide range of imbalance (after all, in the real world, nobody can ever have a high precision balance in their diet), but if you are in imbalance, and want to correct for that, then you should at least be aware of which direction you are out of balance, rather than just snatching the first set of pills you see on the shelves.
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    Offline Bored chemist

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    vitamin suppliments
    « Reply #16 on: 29/03/2007 20:41:29 »
    That's a fair point but what about the fact that twice the recomended intake of most vitamins probably won't do you any harm. You might not know intelectually which nutrients you are short of but the body is quite good at both restricting uptake and increasing excretion of those things it has lots of.
    I know that, since I don't like fresh fruit, I probably miss out on some vitamins and minerals. I take multivitamin pills. I think it's easy enough for my body to sling out the excess of those which it doesn't need, but impossible for it to create them if I take too little.
    With an excess it can maintain the balance; with a shortage it's a bit stuck.
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    Offline iko

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    vitamin suppliments
    « Reply #17 on: 29/03/2007 21:56:42 »
    Quote from: Bored chemist on 29/03/2007 20:41:29
    That's a fair point but what about the fact that twice the recomended intake of most vitamins probably won't do you any harm. You might not know intelectually which nutrients you are short of but the body is quite good at both restricting uptake and increasing excretion of those things it has lots of.
    I know that, since I don't like fresh fruit, I probably miss out on some vitamins and minerals. I take multivitamin pills. I think it's easy enough for my body to sling out the excess of those which it doesn't need, but impossible for it to create them if I take too little.
    With an excess it can maintain the balance; with a shortage it's a bit stuck.

    I agree 100%, Bored chemist.

    You know what I miss in this hightech Era, since my interest in cofactors started a couple of decades ago? A quick and inexpensive full vitamin-cofactor screening test for peripheral blood, a tiny strip of thermal paper with little names and digits, to exclude in seconds a deficiency issue and go on with all the other possible diagnostic hypotheses.
    These days nutritional deficiencies are relatively rare and their treatment quite cheap, so there is no research interest. Nevertheless I cannot accept the idea to rely only on clinical signs, diet and social histories to exclude -for example- a beriberi diagnosis.  This disease was described 120 years ago and the cure is an inexpensive vial in the drawer (thiamine 100mg) plus a sterile syringe. Sometimes it could be too late anyway: it takes approx. 6 hours to restore vital functions.
    There are technical problems too: not in all the vitamin deficiencies you can count on the plasma concentrations for a proper diagnosis, and some cofactors still need sophisticated tests.
    Basically there is no commercial and cultural interest.
    Times are changing a bit now, and you find reports of B12 and folate deficiency in the elderly (not to mention the ongoing vitamin D3 'tsunami') that could have been done at least 20 years ago.
    I remind you B12 deficiency as particularly insidious and tricky.
    We discussed this recently with Dr. Beaver in the 'Pneumonia and dementia' topic:
    http://www.thenakedscientists.com/forum/index.php?topic=6820.0
    I tried to explain how much this issue seems to be neglected by most.

    George seems too much worried to umbalance a natural condition, but I insist in saying that at the recommended doses it might be only a waste of money at worst.
    BTW George, I am still waiting for your comments on the 'Shanghai report' and the engineers versus docs issue...where everything started from, last August.
    When you get bored of vitamin intoxication issues, of course.

    ikod
     
    « Last Edit: 31/10/2007 18:22:09 by iko »
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    paul.fr

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    « Reply #18 on: 30/03/2007 10:42:07 »
    Quote from: Bored chemist on 29/03/2007 20:41:29
    That's a fair point but what about the fact that twice the recomended intake of most vitamins probably won't do you any harm. You might not know intelectually which nutrients you are short of but the body is quite good at both restricting uptake and increasing excretion of those things it has lots of.

    Extracts from a docomentary, interviewing Professor Melhus.


    Professor Melhus: When we look at known risk factors for osteoporosis, such as age, smoking, physical activity, they can partly explain why it's so common with osteoporosis and bone fractures in Sweden, but that can not explain everything. And then, even more surprising, is that we have a diet rich in calcium, which should protect our bones.

    Narration: So Professor Melhus began to look for another explanation. And there was something in particular about the Swedish diet that made him suspicious. It was exceptionally high in vitamin A.

    Professor Melhus: We eat dairy products, oily fish, such as herring and salmon, we consume cod liver oil, vitamin supplements, all which contain high levels of vitamin A, and on top of that we are the only European country which fortifies low fat dairy products with vitamin A.

    Narration: This triggered an alarm for Professor Melhus. Because there was evidence that huge doses of vitamin A damaged animal bones.

    Professor Melhus: Since we knew about these harmful effects of vitamin A on animal bones, we wanted to see if this also could be occurring in humans.

    Narration: So Professor Melhus launched his own investigation. From a database of sixty six thousand women aged over forty, he looked for cases of bone fracture. He then checked the diet of these women to see if their vitamin A intake was particularly high. And the results seemed to confirm his suspicions.

    Professor Melhus: When I saw the results from our study I was really surprised, although I knew the experiments done in animals, it was hard to accept the fact that vitamin A, a vitamin, had negative effects on bone in humans.

    Narration: Professor Melhus then went further. He did a series of bone scans to work out what level of vitamin A was linked to weaker bones. His results suggested that long term consumption of even relatively small quantities of vitamin A were having a dramatic effect.

    Professor Melhus: What we saw was that a vitamin intake above 1.5 milligrams per day, which is approximately twice the recommended daily intake, there was a reduction in bone density about ten per cent, and the risk of hip fracture had doubled.

    Narration: If Professor Melhus was right then the implications were staggering. An intake of 1.5 milligrams per day is a level that can be reached from food alone. And it will be exceeded by taking just a single capsule of some high strength vitamin A supplements. So, tablets that people take every day to improve their health might actually be slowly, silently, weakening their bones. For Professor Melhus, the implication is clear.

    Professor Melhus: Based on our research I think people should continue to eat a healthy, normal balanced diet. But since supplements containing high levels of vitamin A may have adverse effects, I cannot recommend people to take them routinely.

    Narration: Professor Melhus has now done another study that suggests the same risk also applies to men. And since his original work, studies from America have supported his findings, but there has been some other research which has not found the same link.


    Professor Andrew Renwick: I am concerned, although the, the evidence is not totally consistent, there have now been a number of studies showing a link, and I'm convinced that a high intake of vitamin A will give an increase risk of bone fracture.
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    Offline iko

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    vitamin suppliments
    « Reply #19 on: 30/03/2007 17:42:50 »
    Hi paul.fr,

    Good point for a discussion.
    I checked prof. Melhus's report in the NEJMed:

    Serum retinol levels and the risk of fracture.

    Michaelsson K, Lithell H, Vessby B, Melhus H.
    Dept. Surgical Sci., Section of Orthopedics, Univ. Hosp. Uppsala, Sweden. karl.michaelsson@surgsci.uu.se

    BACKGROUND: Although studies in animals and epidemiologic studies have indicated that a high vitamin A intake is associated with increased bone fragility, no biologic marker of vitamin A status has thus far been used to assess the risk of fractures in humans.
    METHODS: We enrolled 2322 men, 49 to 51 years of age, in a population-based, longitudinal cohort study. Serum retinol and beta carotene were analyzed in samples obtained at enrollment. Fractures were documented in 266 men during 30 years of follow-up. Cox regression analysis was used to determine the risk of fracture according to the serum retinol level.
    RESULTS: The risk of fracture was highest among men with the highest levels of serum retinol. Multivariate analysis of the risk of fracture in the highest quintile for serum retinol (>75.62 microg per deciliter [2.64 micromol per liter]) as compared with the middle quintile (62.16 to 67.60 microg per deciliter [2.17 to 2.36 micromol per liter]) showed that the rate ratio was 1.64 (95 percent confidence interval, 1.12 to 2.41) for any fracture and 2.47 (95 percent confidence interval, 1.15 to 5.28) for hip fracture. The risk of fracture was further increased within the highest quintile for serum retinol. Men with retinol levels in the 99th percentile (>103.12 microg per deciliter [3.60 micromol per liter]) had an overall risk of fracture that exceeded the risk among men with lower levels by a factor of seven (P<0.001). The level of serum beta carotene was not associated with the risk of fracture.
    CONCLUSIONS: Our findings, which are consistent with the results of studies in animals, as well as in vitro and epidemiologic dietary studies, suggest that current levels of vitamin A supplementation and food fortification in many Western countries may need to be reassessed.

    N Engl J Med. 2003 Jan 23;348(4):287-94.



    In the introduction you find this phrase:
    "In a study of dietary patterns in Europe, the intake of vitamin A in Scandinavia was up to six times as high as the intake in southern Europe (3)".

    This is a huge difference compared to normal diets, so a risk of toxicity in terms of bone metabolism can be expected.
    Unfortunately, vitamin D levels were not evaluated in such a large study (2322 men).  It's a real pity, because vitamin D interacts closely with retinol (similar receptors) that seems to prevent vitamin D toxicity in terms of calcium metabolism.
    A chance of a deeper look in this complex phenomena has been missed.
    We are used to learn things from little bits here and there.

    ikod


    « Last Edit: 30/03/2007 22:25:48 by iko »
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