Vyazma, What a totally childish response. You really don't care about this issue at all do you? All you seem to care about is that no one tells you what to do. I didn't give you any advice, and I never asked you to take my word for anything. I simply posted the published reviews of the scientific evidence and offered my opinion on them. Why you need to have a tantrum every time I do is beyond me, but the evidence is here for anyone to look at and draw their own conclusions. They don't need to take macgyver's word for what it means, whether he's an MD or not. They don't need to believe my interpretation, whether or not I'm really an "Animal Doctor." And they don't need to blindly follow your opinion, whether you have a Nobel Prize or absolutely no medical education or credentials at all. See, aren't we all nice and free to think and do as we please? So what's the beef?Well great McKenzie. What evidence did you show with that barely readable posting? That Vitamin D doesn't cure cancer? You said there was "evidence here for anyone to look at and draw their own conclusions." What evidence did you show? Did that show that vitamin D supplementation is ineffective for providing vitamin D into the human body? -then I suppose it won't be long before the government stops requiring milk to be fortified with Vitamin D...Right? Did that "evidence" you posted show that humans don't need vitamin D? Did it show that humans cannot get vitamin D from supplementation? Go ahead I'll stop there and see if you can handle these simple questions. 7 questions there...take as many or as few as you wish. I'll wait.
I don't have time to give you an education in vitamin D metabolism here nor is it relevant to the point. No one here said the human body doesn't need vitamin D. What I said is that there is no current evidence that Vitamin D supplements are beneficial or necessary for most people to take. They could be helpful, harmful, or harmless. The fact is that no one knows at this point and anyone who says they do is misinformed.So you don't know why the body needs vitamin D then? You're saying the FACT is that no one knows whether vitamin D supplements introduce vitamin D into the human body for metabolization? You just agreed that the human body needs vitamin D. But you are saying that no one knows whether a vitamin D supplement will physically introduce vitamin D into the human body for use and metabolization? Here we go again MacGeyver...here we go again. Now you get to scramble around stumbling and fumbling as you try to beat around this bush. Vitamins are food Macgeyver. Food! Of course they are beneficial and necessary to take! How could you possibly say that there is no evidence of this?
“Congress defined the term “dietary supplement” "
Consistent with what I told you earlier, the FDA didn’t define the term dietary supplement. A bunch of ill informed scientifically illiterate senators and congressmen led by Orin Hatch ( an even more scientifically illiterate senator) drafted that definition at the behest of the supplement industry in order to free themselves from FDA oversight.
Vitamins don;t suddenly become non-drugs simply because a group of politicians decide they aren’t drugs. the FDA did not agree with this decision and in fact lobbied against the legislation. As I said before, they are a governmental agency and are required to follow the law whether they agree with it or not once its been passed and signed into law. Congress shouldnt be legislating science for this very reason. They dont know what they are talking about or what they are doing when it comes to science.
I guess you didn’t read the earlier post where I addressed this (mentioned an ignorant senator who pushed through legislation in 1994).
It occurred to me that this topic is similar to those of politics and theology. We all start out with our views, be it existence or nonexistence of a god, conservative or liberal, or pro or anti supplements, then in our reading we give greater value to those articles which agree with our beginning beliefs. :) OccamOccam as a scientist you should no better. As with all elements of science there can be areas of disagreement but in the end the data speaks for itself. The argument you are using here is the same one creationists, climate deniers, and anti-vaxers use to make it look like there are two equal sides to an argument when the data in fact comes down pretty conclusively on one side or the other. There may be some supplements and vitamins that have benefits under certain circumstances although most dont. There are many different supplements and many different claims about them. Some of these things have been decided on the same level as evolution in that there is a consensus that negates any real debate. Others may still be open for discussion, but to imply that evidence is so unclear that each of us might as well pick and choose which data we prefer to believe is like saying we can pick and choose the data concerning evolution and make decisions based on our personal biases. You can do that but not if your real interest is to find the truth. When it comes to supplements and vitamins the logic here is pretty clear, although some on this forum fail to grasp it. Supplements and vitamins are not magic. Most supplements are likely inert with no effects good or bad. If they have a beneficial effect in the body they should be treated just like any other drug in that they are likely to also have unintended side effects. This is why its important for people to understand that these are drugs. Labeling them as supplements imparts a magical ( and imaginary) quality to them with a promise of benefits with no side effects. While people are obviously free to do what they like on their own, supplement makers should not be allowed to manufacture and promote products to the public without evidence that the products are safe and effective based on sound randomized controlled trials of the same quality as all other drugs. Supplements are not some magic class of substances that are capable of providing benefit free of the possibility of side effects. This artificial classification should be abolished. They either have effects and side effects which means they are a drug and should be regulated as such or they are inert with no benefits to consumers and should be labeled as such.
I don't have time to give you an education in vitamin D metabolism here nor is it relevant to the point. No one here said the human body doesn't need vitamin D. What I said is that there is no current evidence that Vitamin D supplements are beneficial or necessary for most people to take. They could be helpful, harmful, or harmless. The fact is that no one knows at this point and anyone who says they do is misinformed.So you don't know why the body needs vitamin D then? You're saying the FACT is that no one knows whether vitamin D supplements introduce vitamin D into the human body for metabolization? You just agreed that the human body needs vitamin D. But you are saying that no one knows whether a vitamin D supplement will physically introduce vitamin D into the human body for use and metabolization? Here we go again MacGeyver...here we go again. Now you get to scramble around stumbling and fumbling as you try to beat around this bush. Vitamins are food Macgeyver. Food! Of course they are beneficial and necessary to take! How could you possibly say that there is no evidence of this? I think what McGyver is saying is that although vitamins are found in food, it doesn't mean they can be extracted from food--or made synthetically--and have any beneficial effect. So far many lab tests show that their effect is minimal at best and some could be harmful. There probably is not a great deal of harm caused by taking vitamin supplements but why spend money on and take something that has not been shown to have a beneficial effect? I agree with his premise. But anyone is free to take supplements if he wishes to despite a lack of evidence that they are doing any good and some could do real harm. They probably will have little effect but to waste your money. He has shown that most doctors don't know squat about vitamin supplements but many have been taken in by the hype. Everyone wants to find a magic pill, even doctors. Lois
Well, I didn't pressure my PCP to prescribe Vit. D. As I said, I questioned it. I did, OTOH, lobby for him to allow me to try fish oil for a few months to address my cholesterol (instead of immediately starting Lipitor or some equivalent). He basically said that the fish oil would not help in a significant way, but went along with my wishes, for the time being, as I stressed my concerns about statins potential effects on the liver. So you would be skeptical of my PCP's stance on Vit. D in my case, but I imagine that you would not be skeptical of his stance on the fish oil. BTW, the vit D was a 3 month prescription.Did you need a prescription for something that is widely available over the counter for a lot less money? As for fish oil, he was probably being honest in saying it would probably not help in any significant way but that he sees no harm in it. What else could he say? He probably knows that his patients will take things whether he advises against it or not. The only thing he can do is pass on the information he has. What you do with it is up to you. He only has so much influence over what his patients do despite his advice. But if I were your doctor I wouldn't have given you a prescription for Vitamin D. I would have told you that what you get over the counter will be as helpful or as harmful as what you would get with a prescription; it would just cost more. Lois
Perhaps you will show me where the FDA says that supplements and vitamins are not a drug first.From the FDA's website, under the Q&A section in FDA/Food/Supplements. What is a dietary supplement? Congress defined the term "dietary supplement" in the Dietary Supplement Health and Education Act (DSHEA) of 1994. A dietary supplement is a product taken by mouth that contains a "dietary ingredient" intended to supplement the diet. The "dietary ingredients" in these products may include: vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites. Dietary supplements can also be extracts or concentrates, and may be found in many forms such as tablets, capsules, softgels, gelcaps, liquids, or powders. They can also be in other forms, such as a bar, but if they are, information on their label must not represent the product as a conventional food or a sole item of a meal or diet. Whatever their form may be, DSHEA places dietary supplements in a special category under the general umbrella of "foods," not drugs, and requires that every supplement be labeled a dietary supplement. There you go Macgyver. The FDA considers them under the umbrella of foods-NOT drugs. Who wouldn't think that? Drugs are things designed to cure illnesses, treat symptoms, and relieve people of ailments. Foods are things people eat to supply their bodies with nutrients and calories and vitamins. You and Mckenzie keep getting this mixed up. It isn't that the FDA considers them as foods and not drugs. That decision was imposed on them by laws passed by Congress. The FDA wanted them to be classed as drugs. They lost that round. Supplements are not actually foods. They are mostly synthesized in a laboratory as appearing to be what is found in foods. No one knows whether they act on the body the same way as those elements act if taken as food. You are in dangerous territory if you depend on the FDA to tell you everything you need to know without looking beneath the surface and at what role politics plays in what they do or say. What the FDA can or can't say or do is controlled by legislators, not scientists, and much of it is uninformed and harmful. Lois
It isn't that the FDA considers them as foods and not drugs. That decision was imposed on them by laws passed by Congress. The FDA wanted them to be classed as drugs. They lost that round. Supplements are not actually foods. They are mostly synthesized in a laboratory as appearing to be what is found in foods. No one knows whether they act on the body the same way as those elements act if taken as food. You are in dangerous territory if you depend on the FDA to tell you everything you need to know without looking beneath the surface and at what role politics plays in what they do or say. What the FDA can or can't say or do is controlled by legislators, not scientists, and much of it is uninformed and harmful. LoisI know exactly what was behind DSHEA. The law specifically states that supplements cannot make claims that drugs can make. IE they cannot claim to cure, treat, diagnose, or otherwise alleviate illnesses or symptoms of illnesses. I know that many supplements are bending these laws. Vitamin, herbal, enzyme, protein supplements etc. I'm not interested in these products. Weight loss, muscle builders, testosterone builders, sex drive herbs, urinary supplements and the hundreds of other quack-jobs out there. Just because there are alot of bad apples doesn't mean the whole bushel is rotten! I'm also not interested in people making claims that vitamins can cure, treat, diagnose or otherwise relieve ailments. Part of DSHEA and the FDA states that supplements must label ingredients and must have scientific consensus behind these ingredients. If a reputable company such as Pfizer, who makes Centrum Multi-vitamins, labels their products and lists amounts of the ingredients, then I would like someone to show me that the Iron for example, in these tablets is fake iron and will not be metabolized in the human body. Can someone show me that the Iodine is fake? The Vitamin A? etc etc etc... Is somebody here trying to make the claim that these tablets which claim to have these vitamins are fake and contain no vitamins that will actually be absorbed and metabolized by the body? Consider that they are under the scrutiny of the FDA, the private watchdogs, the buying public, and these tablets regularly are tested for ingredients and function. *So..once again, first show proof that the human body doesn't need vitamin A, D, iron, iodine or potassium for example. *If you can't show this, the next step is to show that a particular product lies about the ingredients and amounts. *If you can do this great, it should be banned, fined etc. *For the ones that are found to contain these compounds and amounts correctly, you must next show that the ingredients for some reason cannot be absorbed and utilized by the human body. After that, simple vitamin supplements which contain amounts of vitamins which are safe and equal to or less than the amounts found in a normal serving of food should be absolutely fine and treated as food. Which is exactly what the FDA says they are.
I don’t think the two Ms are claiming that the supplements are evil, Vy, just that no one needs them because all of Americans get adequate amounts of all the supplements in our diets so we’re wasting money by taking them. After all, we have to recognize the value of the fast food industry in their efforts to provide low fat, low calorie, high quality foods which supply all our nutritional needs to everyone. :lol:
Of course, the response to this is: Americans should work to eat an adequate diet rather than the junk foods. And that’s true, just as is: Americans should all be atheistic, liberal, humanists who care for and respect each other.
Occam
Vyazma,
The evidence was a systematic review of 107 other systematic reviews and 74 meta-analyses, involving hundres of studies with thousands of people, which found that “despite a few hundred systematic reviews and meta-analyses, highly convincing evidence of a clear role of vitamin D does not exist for any outcome, but associations with a selection of outcomes are probable.” That’s the evidence I provide which you can interpret in whatever way you like. The questions you ask are totally irrelevant to the paper I posted, so I have no idea why you keep bringing them up. Read it for yourself and do whatever you like with the information.
Occam,
While I agree we all tend to interpret the evidence in the light most favorable to our preconceptions, it’s not a simple matter of picking and choosing one paper over another in this case. The review I cited is a systematic review of hundreds of studies, so it is as close as we are likley to get to an impartial assessment of the preponderance of the evidence. It requires a pretty strong commitment to a belief to dismiss evidence at this level.
It isn't that the FDA considers them as foods and not drugs. That decision was imposed on them by laws passed by Congress. The FDA wanted them to be classed as drugs. They lost that round. Supplements are not actually foods. They are mostly synthesized in a laboratory as appearing to be what is found in foods. No one knows whether they act on the body the same way as those elements act if taken as food. You are in dangerous territory if you depend on the FDA to tell you everything you need to know without looking beneath the surface and at what role politics plays in what they do or say. What the FDA can or can't say or do is controlled by legislators, not scientists, and much of it is uninformed and harmful. LoisI know exactly what was behind DSHEA. The law specifically states that supplements cannot make claims that drugs can make. IE they cannot claim to cure, treat, diagnose, or otherwise alleviate illnesses or symptoms of illnesses. I know that many supplements are bending these laws. Vitamin, herbal, enzyme, protein supplements etc. I'm not interested in these products. Weight loss, muscle builders, testosterone builders, sex drive herbs, urinary supplements and the hundreds of other quack-jobs out there. Just because there are alot of bad apples doesn't mean the whole bushel is rotten! I'm also not interested in people making claims that vitamins can cure, treat, diagnose or otherwise relieve ailments. Part of DSHEA and the FDA states that supplements must label ingredients and must have Oscientific consensus behind these ingredients. If a reputable company such as Pfizer, who makes Centrum Multi-vitamins, labels their products and lists amounts of the ingredients, then I would like someone to show me that the Iron for example, in these tablets is fake iron and will not be metabolized in the human body. Can someone show me that the Iodine is fake? The Vitamin A? etc etc etc... Is somebody here trying to make the claim that these tablets which claim to have these vitamins are fake and contain no vitamins that will actually be absorbed and metabolized by the body? Consider that they are under the scrutiny of the FDA, the private watchdogs, the buying public, and these tablets regularly are tested for ingredients and function. *So..once again, first show proof that the human body doesn't need vitamin A, D, iron, iodine or potassium for example. *If you can't show this, the next step is to show that a particular product lies about the ingredients and amounts. *If you can do this great, it should be banned, fined etc. *For the ones that are found to contain these compounds and amounts correctly, you must next show that the ingredients for some reason cannot be absorbed and utilized by the human body. After that, simple vitamin supplements which contain amounts of vitamins which are safe and equal to or less than the amounts found in a normal serving of food should be absolutely fine and treated as food. Which is exactly what the FDA says they are. It's up to the vitamin makers to show that their vitamins are effective and that their vitamin pills have in them what they claim. It is also up to them to show that vitamins have a positive effect on the human body, especially on those who have no diagnosed deficiency, and that they do no harm. It is not up to the skeptics to prove anything. I would have thought you knew this. The burden of proof is on the claimant, not the people to whom the claims are being made--and not even the FDA. . . . the Food and Drug Administration doesn’t regulate dietary supplements as drugs — they aren’t tested for safety and efficacy before they’re sold. Many aren’t made according to minimal standards of manufacturing (the F.D.A. has even found some of the facilities where supplements are made to be contaminated with rodent feces and urine). And many are mislabeled, accidentally or intentionally. They often aren’t what they say they are. For example: In 2003, researchers tested “ayurvedic" remedies from health food stores throughout Boston. They found that 20 percent contained potentially harmful levels of lead, mercury or arsenic. In 2008, two products were pulled off the market because they were found to contain around 200 times more selenium (an element that some believe can help prevent cancer) than their labels said. People who ingested these products developed hair loss, muscle cramps, diarrhea, joint pain, fatigue and blisters. Last summer, vitamins and minerals made by Purity First Health Products in Farmingdale, N.Y., were found to contain two powerful anabolic steroids. Some of the women who took them developed masculinizing symptoms like lower voices and fewer menstrual periods. Last month, researchers in Ontario found that popular herbal products like those labeled St. John’s wort and ginkgo biloba often contained completely different herbs or contaminants, some of which could be quite dangerous. The F.D.A. estimates that approximately 50,000 adverse reactions to dietary supplements occur every year. And yet few consumers know this.. http://www.nytimes.com/2013/12/15/opinion/sunday/skip-the-supplements.html?_r=0 Lois
Well, I didn't pressure my PCP to prescribe Vit. D. As I said, I questioned it. I did, OTOH, lobby for him to allow me to try fish oil for a few months to address my cholesterol (instead of immediately starting Lipitor or some equivalent). He basically said that the fish oil would not help in a significant way, but went along with my wishes, for the time being, as I stressed my concerns about statins potential effects on the liver. So you would be skeptical of my PCP's stance on Vit. D in my case, but I imagine that you would not be skeptical of his stance on the fish oil. BTW, the vit D was a 3 month prescription.Did you need a prescription for something that is widely available over the counter for a lot less money? As for fish oil, he was probably being honest in saying it would probably not help in any significant way but that he sees no harm in it. What else could he say? He probably knows that his patients will take things whether he advises against it or not. The only thing he can do is pass on the information he has. What you do with it is up to you. He only has so much influence over what his patients do despite his advice. But if I were your doctor I wouldn't have given you a prescription for Vitamin D. I would have told you that what you get over the counter will be as helpful or as harmful as what you would get with a prescription; it would just cost more. Lois I agree with what you suggest about the fish oil and my PCP's stance. Re: the Vit D: I didn't ask for it. I was a bit skeptical. I haven't shopped around, but my guess is that for the 14 capsules of 50,000 IU would have cost me more, over the counter, than the prescription, which my insurance paid for (resulting in me paying $0.00 for it out of pocket). I apologize for probably unnecessarily contributing in a small way to the national cost of healthcare. But I am paying something for the healthcare insurance and my PCP must have thought it was important that I take the Vit D. But as I said, he also must have thought it important that I start a statin medication. I wasn't as concerned about the possible negative effects of Vit D as I was about those of a statin.
Well, I didn't pressure my PCP to prescribe Vit. D. As I said, I questioned it. I did, OTOH, lobby for him to allow me to try fish oil for a few months to address my cholesterol (instead of immediately starting Lipitor or some equivalent). He basically said that the fish oil would not help in a significant way, but went along with my wishes, for the time being, as I stressed my concerns about statins potential effects on the liver. So you would be skeptical of my PCP's stance on Vit. D in my case, but I imagine that you would not be skeptical of his stance on the fish oil. BTW, the vit D was a 3 month prescription.Did you need a prescription for something that is widely available over the counter for a lot less money? As for fish oil, he was probably being honest in saying it would probably not help in any significant way but that he sees no harm in it. What else could he say? He probably knows that his patients will take things whether he advises against it or not. The only thing he can do is pass on the information he has. What you do with it is up to you. He only has so much influence over what his patients do despite his advice. But if I were your doctor I wouldn't have given you a prescription for Vitamin D. I would have told you that what you get over the counter will be as helpful or as harmful as what you would get with a prescription; it would just cost more. Lois I agree with what you suggest about the fish oil and my PCP's stance. Re: the Vit D: I didn't ask for it. I was a bit skeptical. I haven't shopped around, but my guess is that for the 14 capsules of 50,000 IU would have cost me more, over the counter, than the prescription, which my insurance paid for (resulting in me paying $0.00 for it out of pocket). I apologize for probably unnecessarily contributing in a small way to the national cost of healthcare. But I am paying something for the healthcare insurance and my PCP must have thought it was important that I take the Vit D. But as I said, he also must have thought it important that I start a statin medication. I wasn't as concerned about the possible negative effects of Vit D as I was about those of a statin. If you can get a prescription filled for no extra cost to you, then go with it. I don't have a plan that pays for 100 % of my prescription costs. In fact, I'm not sure if my plan would pay for a vitamin supplement at all. But if you have such a plan, then go with it. Let us know what happens. My own doctor said there is no effective substitute for statins, but if you can get your cholesterol levels down with vitamins, I might try it myself because my body does not tolerate statins. Lois
"despite a few hundred systematic reviews and meta-analyses, highly convincing evidence of a clear role of vitamin D does not exist for any outcome, but associations with a selection of outcomes are probable."What does this mean? Does this mean that we don't need vitamin D? What does "associations with a selection of outcomes are possible" mean? McKenzie, explain what this means. McKenzie please, I'd like McKenzie to explain it thank you.
My own doctor said there is no effective substitute for statins, but if you can get your cholesterol levels down with vitamins, I might try it myself because my body does not tolerate statins. LoisI'll let you know what happens with my cholesterol levels. I am not overly optimistic. But even if my levels turn out to look better, it doesn't necessarily follow that it would work for you. I could just be an outlier.
Vyazma,
The best thing, of course, would be for you to read the paper yourself (HERE]'s the link). I do understand, though, that it’s a dense scientific paper that requires some specific training in statistics and critical appraisal to understand, and just as I’m no expert in your field, I don’t expect everyone to be an epidemiologist, so I will try to convey the gist. I will admit, though, that based on the rest of this thread I am skeptical that you really want to understand what this paper is about, and I fear you are just looking for points to attack or fit into the previous fruitless debate. Still, here’s hoping we can leave that behind and do better from here on.
The paper reviewed the results of hundreds of studies looking at whether or not there was any relatonship between taking a Vitamin D supplement and one’s state of health. I understand you believe that taking the supplement is simply getting Vitamin D just like you would from food and that you don’t think it has anything to do with health. But you also seem to believe that you are in some way healthier or better off for taking it than you would be if you stopped, presumably because you aren’t convinced that your diet contains enough Vitamin D without adding the supplement to it. This paper is looking at exactly that question: Are people who take Vitamin D supplements any better off than if they didn’t take one?
The review examined both previous reviews of observational studies (studies where investigators just looked at people who did or did not take a supplement on their own) and experimental studies (where people were deliberately given a Vit D supplement or a placebo). It looked at what are called “outcomes,” meaning what happened to the people in the studies in terms of their health. Becaue of what Vitamin D is know to do in the body, many of these outcomes were things Vit D might be expected to affect (either becuase people got too little in the diet and the supplement fixed that deficiency or because adding a supplement to the diet was better than not adding one regardless of how much Vit D was obtained from food). The outcomes included things like falls and broken bones in old people, cavities in children, cancer, and so on, all things Vit D might affect given what it does in the body.
The results found that taking a supplement didn’t clearly affect any of the outcomes looked at. In other words, for most people it didn’t seem to matter for their health if they took a Vit D supplment or not. There were a couple of outcomes that might have been affected, but the data wasn’t completely clear (this is the “probable association with selected outcomes”). It might be that if pregnant women take Vit D this affects the birth weight of their babies, that Vit D supplements might affect the risk of cavities in children, it might affect a certain important hormone that is an issue for people with kidney disease, and so on. So the overall conclusion was that despite hundreds of studies in thousands of people, it doesn’t seem like taking a Vit D supplement has any effect on health excpet possibly for a few specific things.
Sure, you get Vit D from a Vit D supplement, and the body uses Vit D, but so what? If it doesn’t have any measurable effect on health whether you take it or not, what is the point of taking it?
Put another way, the body needs water, and you get water from drinking a glass of water. But if drinking one extra glass of water a day has no effect on your health, why make a point of doing it? It’s the same with Vit D.
Now the issue not addressed in this study was is there any harm to taking a Vit D supplement even if it doesn’t do anything useful. At this point, it seems unlikley that there is any harm for most people at reasonable doses. But as I’ve said before we thought the same thing in the past about other vitamins and turned out to be wrong in some cases. Vit E supplements can actually icnrease the risk of strokes in some people, for example. So for most people, the evidence suggests that taking a Vit D supplement is probably doing nothing good or bad, but as always in science more research will give us more iformation about who might benefit and who might be harmed. The devil is in the details.
Anyway, as I’ve said many times, I’m not telling you what to do or not to do. I just put the paper out there because I think reviewing the scientific evidence and using it to guide our choices is the best way to approach these things.
Vyazma, Anyway, as I've said many times, I'm not telling you what to do or not to do. I just put the paper out there because I think reviewing the scientific evidence and using it to guide our choices is the best way to approach these things.What kinds of actions will be taken as a result of this scientific paper you cited?
What kinds of actions will be taken as a result of this scientific paper you cited?The ideal action would be for physicians to stop recommending Vit D supplements to their patients except in the rare circumstance where there is a proven need or benefit. Additionally one would hope that the information would trickle down to patients allowing them to make decisions about their own Vit D consumption based on good science rather than the rumor, hearsay, flawed reasoning, and pseudoscientific claims that permeate much of the discussion about vitamins and supplements.
As macgyver said, the value of systematic reviews is they give an overview of the balance of the evidence which doctors and everyone else can use to guid their choices. If the evidence seems pretty clear that there is no difference in health for most people beteen taking and not taking a Vit D supplement, presumably octors will tell their patients this and they can make a fully informed choice about what to do. Conversly, if the evidence had shown strong reason to believe Vit D supplements had benefits in some circumstances, doctors and publich health officials might encourage people in those circumstances to take them. Ideally, policy and patient education should be driven by research evidence as far as is possible.
Without going into the details of this report(I went and skimmed it) and the scope of what it covers, what previous reports or studies
does this report supersede?
For example, back in 2009 Doug Smith posted a thread about studies that said Vitamin D supplements were recommended.
He cited 3 different sources.(search: “Vitamin D”; pg. 3 or 4 I think.)
This study here above supersedes these past studies beyond a shadow of doubt or debate?
Also it is important to note that this study only covers Vitamin D and not other vitamin supplements or vitamins.