What's the percentage of recommended daily intakes of vitamins and minerals in an "average daily diet"?I don't know nor does it really matter. The question is whether adding to that intake with additional vitamin supplements will improve that persons health and the answer seems to be no. Your attempts to quantify it and turn it into a mathematical equation which can be solved by balancing one side (intake) to equal the other (requirements) doesn't work for the reasons I stated above. It doesn't really matter? What if a kid ate only 2 Twinkies and can of Coke a day? That was his daily average intake. Plus the answer seems to be yes, it does matter if vitamin supplements are added. That's why they are added to flour and milk for example. You have yet to say what an average daily diet is MacGeyver.
What's the percentage of recommended daily intakes of vitamins and minerals in an "average daily diet"?I don't know nor does it really matter. The question is whether adding to that intake with additional vitamin supplements will improve that persons health and the answer seems to be no. Your attempts to quantify it and turn it into a mathematical equation which can be solved by balancing one side (intake) to equal the other (requirements) doesn't work for the reasons I stated above. It doesn't really matter? What if a kid ate only 2 Twinkies and can of Coke a day? That was his daily average intake. Plus the answer seems to be yes, it does matter if vitamin supplements are added. That's why they are added to flour and milk for example. You have yet to say what an average daily diet is MacGeyver. I think you have a misperception. When these studies are done they do not define an "average diet" and then proceed to find people who's diets fulfill that criteria. They instead study thousands of people chosen at random. The "average diet" in the study is just the average of that group of people and if the group is large enough the average should be representative of the average diet of America as a whole. Obviously a person eating twinkies and a can of coke is not a typical diet. If that is what you've been eating Vyazma then I understand your desire to take vitamins but your efforts would be as effective as putting a fresh coat of paint on a boat that's full of holes. The boat is still going to sink.
This thread has included references to a number of scientific studies, opinion pieces, and evidence-based guidelines. I thought it would be useful to collect them all in one place, and that led to my putting together a bibliography of papers and posts from Science-Based Medicine illustrating why the idea that general, non-targeted use of vitamin and mineral supplements is safe or effective. For those interested, here is a link to that collection:
Evidence Concerning Vitamin and Mineral Supplements- Safety and Efficacy]
I think you have a misperception. When these studies are done they do not define an "average diet" and then proceed to find people who's diets fulfill that criteria. They instead study thousands of people chosen at random. The "average diet" in the study is just the average of that group of people and if the group is large enough the average should be representative of the average diet of America as a whole.Ok, excellent definition of average diet. I get it. If the sample group is large enough I agree that would be a good cross section of an average diet. Now what else does everybody in the study have in common? You still working on an an answer for this question MacGeyver? You stated that an average diet was sufficient enough for a person to get all of their nutritional needs. I'm just curious what this latest study you hinted at here above was that determined that. I want to clear up any misconceptions I have about what you meant about an average diet. How is an average diet by your definition above ensuring that people are meeting the FDAs recommendations for daily intakes? How did the study you intimate at show this?
It seems to me, the average American diet is high in things like McBurgers and McFries or other greasy spoons, leading to higher cholesterol and obesity, which in turns leads to a lot of heart problems. So, if the studies in McKenzie’s blog involved the average American diet, then I would say there’s a problem right off the bat with those studies. Here’s the studies I’d like to see- Vegans taking vitamins due to the lack of dairy/calcium in their diets, Anorexics and vitamins while in treatment, and other extremes of the norm that don’t include people living on the typical American diet. Meanwhile, I’ll eat my tofu patty, with lettuce, tomato, spinach, pickles, cucumbers, green peppers, black olives, mushrooms, and cheddar cheese, on whole wheat, with a side of fruit. Thank you. Hopefully, that covers my nutritional needs, because I eat a lot of such things.
Mac Geyver I hope you find the time to answer my question regarding the study you hinted at.
The study that considers the diets of all participants concerned the average diet.
Because you had stated that the average diet was enough for people to get their daily intakes of FDA recommended vitamins and minerals.
I’m still curious what this study you hint at shows concerning the average diet of all the participants.
You are a strange man, VYAZMA.
Mriana,
Well, the applicability of any study depends on whether the group we want to apply it to is sufficiently similar to the group in the study. If we study tens of thousands of Americans, it is likely that the “average diet” takes into account a pretty wide range of variation in dietary habits, and the results are pretty broadly applicable. Most people in America probably don’t need the vitamin supplements they are taking, which is the main point I have been making.
However, if you are specifically interested in a very narrow question, such as vegans taking calcium supplementation, you would of course want research data looking specifically at that question. The devil is always in the details, and the trick in science is to generate data that is well-suited to answering a specific, well-defined question like this.
A cursory search of PubMed didn’t turn up much research aimed at this subject. One paper did seem to find a deficiency of calcium in healthy young vegans in Sweden. Interestingly, it also found that even those taking supplements were deficient, suggesting the supplements may not have been effective or they weren’t using them properly:
Am J Clin Nutr. 2002 Jul;76(1):100-6. Dietary intake and nutritional status of young vegans and omnivores in Sweden. Larsson CL, Johansson GK. Abstract BACKGROUND: Adolescents sometimes become vegetarian for ethical rather than health reasons. This may result in health problems caused by lack of interest in and knowledge of nutrition. OBJECTIVE: We compared the dietary intake and nutritional status of young Swedish vegans and omnivores. DESIGN: The dietary intakes of 30 vegans (15 males and 15 females; mean age: 17.5 +/- 1.0 y) and 30 sex-, age-, and height-matched omnivores were assessed with the use of a diet-history interview and validated by the doubly labeled water method and by measuring nitrogen, sodium, and potassium excretion in urine. Iron status and serum vitamin B-12 and folate concentrations were measured in blood samples. RESULTS: The diet-history method underestimated energy intake by 13% and potassium intake by 7% compared with the doubly labeled water method and 24-h urine excretion, respectively. Reported dietary nitrogen and sodium intakes agreed with the 24-h urinary excretion measure. Vegans had higher intakes of vegetables, legumes, and dietary supplements and lower intakes of cake and cookies and candy and chocolate than did omnivores. Vegans had dietary intakes lower than the average requirements of riboflavin, vitamin B-12, vitamin D, calcium, and selenium. Intakes of calcium and selenium remained low even with the inclusion of dietary supplements. There was no significant difference in the prevalence of low iron status among vegans (20%) and omnivores (23%). Two vegans with low intakes of vitamin B-12 had low serum concentrations. CONCLUSION: The dietary habits of the vegans varied considerably and did not comply with the average requirements for some essential nutrients.This fits quite nicely with what I've been saying, which is that there are certainly situations in which vitamin and mineral are appropriate, but they have to be identified through properly targeted scientific research. Most people, unfortunately, either assume such supplements are safe and beneficial or improperly generalize from research not really designed to answer the questions they are asking.
Mriana, Well, the applicability of any study depends on whether the group we want to apply it to is sufficiently similar to the group in the study. If we study tens of thousands of Americans, it is likely that the "average diet" takes into account a pretty wide range of variation in dietary habits, and the results are pretty broadly applicable. Most people in America probably don't need the vitamin supplements they are taking, which is the main point I have been making.I think the "average American diet" is way to broad for such a study and for it to be a valid one. I really think such studies should be narrowed down to specific groups, divided into those with vitamin supplements and those without for it to truly be valid. Iron studies, such as what you posted are ridiculous because vegans can get iron from spinach, broccoli, and other vegetable sources. unless they are wannabe child vegans with possible eating disorders, which your article insinuates. Unless they avoid those sources, they aren't going to be deficient in iron. This makes the research seriously skewed and flawed IMHO, because it tested for things found in a vegan proper balanced diet on those wannabe child vegans, who may or may not have an eating disorder, just reading the abstract. Test for things not found in a proper vegan diet, but are in an omnivore diet and see if supplements help such deficiencies.
However, if you are specifically interested in a very narrow question, such as vegans taking calcium supplementation, you would of course want research data looking specifically at that question. The devil is always in the details, and the trick in science is to generate data that is well-suited to answering a specific, well-defined question like this.IMHO, that's how the studies should be- much narrower. more specific, and not as broad for them to actually be valid for the general population. Of course, one study is not enough to base anything. The tests need to be repeated to see if researchers get the same results. Thus, there needs to be more than one study examined. IMHO.
This fits quite nicely with what I've been saying, which is that there are certainly situations in which vitamin and mineral are appropriate, but they have to be identified through properly targeted scientific research. Most people, unfortunately, either assume such supplements are safe and beneficial or improperly generalize from research not really designed to answer the questions they are asking.It may fit nicely, but it is only one study and one that you chose because it fits what you believe, but you didn't dare post a link to what didn't validate your opinion, even if it was a PubMed study and there are some that contradict what you say in PubMed's collections of studies. We need more than just that, because anything else is bias on the person giving the link view. We need several studies on the same topic, that may or may not necessarily validate your opinion, in which to make our own informed decision about the topic. Give me something that doesn't test child vegans who might have an eating disorder. I feel like my intelligence was just insulted.
You are a strange man, VYAZMA.What makes you say that George, if you don't mind me asking?
I feel like my intelligence was just insulted.That's how I felt when I asked MacGeyver what an "average diet" was. He then proceeded to explain that an "average diet" was what the average diet was of all participants in a controlled study. What study? What were they studying?
What's the percentage of recommended daily intakes of vitamins and minerals in an "average daily diet"?I don't know nor does it really matter. The question is whether adding to that intake with additional vitamin supplements will improve that persons health and the answer seems to be no. Your attempts to quantify it and turn it into a mathematical equation which can be solved by balancing one side (intake) to equal the other (requirements) doesn't work for the reasons I stated above. No that's not the question. Can you define what "improve health" means? I'm not claiming vitamins "improve" health. I'm claiming that supplements can improve diets if a person knows that their individual diet doesn't conform to the FDAs listed Recommended Daily Intakes of vitamins a and minerals. A diet that falls below these recommendations is a poor diet. This can be improved through supplementation. Nobody here is making any claims that vitamins improve health. I'm claiming they improve diet. Your saying that the amount of vitamins in a persons diet doesn't matter. I can't believe a doctor would say that.
What's the percentage of recommended daily intakes of vitamins and minerals in an "average daily diet"?I don't know nor does it really matter. The question is whether adding to that intake with additional vitamin supplements will improve that persons health and the answer seems to be no. Your attempts to quantify it and turn it into a mathematical equation which can be solved by balancing one side (intake) to equal the other (requirements) doesn't work for the reasons I stated above. No that's not the question. Can you define what "improve health" means? I'm not claiming vitamins "improve" health. I'm claiming that supplements can improve diets if a person knows that their individual diet doesn't conform to the FDAs listed Recommended Daily Intakes of vitamins a and minerals. A diet that falls below these recommendations is a poor diet. This can be improved through supplementation. Nobody here is making any claims that vitamins improve health. I'm claiming they improve diet. Your saying that the amount of vitamins in a persons diet doesn't matter. I can't believe a doctor would say that. We've been through this before Vyazma. How can you claim that a diet is improved if it doesn't improve your health? By what definition is a diet improved or better if it doesn't result in a healthier individual? If your definition is simply that it meets some list of suggested nutritional requirements then the definition is entirely meaningless if that doesn't ultimately result in a better outcome in some way for the person on the "improved diet". A good diet is one that results in a healthier individual. The only valid argument you could have is that vitamin supplementation improves some element of health that we haven't measured yet but if that's the case there is no proof and therefor no reason to support the use of vitamins. To do so would simply be an act of faith, but good skeptics don;t generally act on faith. To answer your earlier question about the "average diets" of patients in these studies, I was not referring to any one particular study but simply describing the manner in which most such studies are done. Many of these studies are retrospective which means they ask people about their vitamin intake and then ask them about their illnesses and look for a correlation. As we have often discussed here there are advantages and disadvantages to retrospective studies. The advantages are that you can study large numbers of people, the studies take months instead of decades and they cost a small fraction of what a randomized trial cost. The disadvantages are that people don't always recall and report things accurately, sometimes they shade their answers if they have a theory about the nature of the study, and most importantly, the individuals are not randomly assigned to the treatment and control groups so there may be other important variables that differentiate the two groups and account for the difference in outcomes. For example vitamin users may be more health conscious and follow other healthy activities like better diet and more exercise. This could artificially skew the results to make it look like vitamin users have better health outcomes. Conversely cancer patients have been known to turn to vitamins in desperation. The vitamin user group could therefor have more cancer patients in it and this could aritifically increase the mortality rate in the vitamin user group. You can find a link to one of these retrospective studies HERE]. This study involved over 77,000 people so it was a good sample size but you will notice that they did not as about diet or restrict enrollment according to diet so one can assume they represent a broad spectrum of diets and as a whole they are a good representation of the average diet in the pacific northwest and perhaps the country as a whole. There are a fair number of RCT's that look at the affect of vitamins on mortality but most of them are in patients with specific disease like cancer and heart disease. The primary reason is that the longer the life expectancy of the participants the longer it takes to do the study. Longer studies also have higher rates of participant dropout and are more expensive to do. Obviously people suffering from heart disease and cancer don't have long life expectancies so they are easier to study. These patients also have more to gain if a beneficial effect is found.
You are a strange man, VYAZMA.What makes you say that George, if you don't mind me asking? Because you are asking strange questions. I don't think macgyver could be any clearer. I know you are trying hard to find something wrong with what he's saying, but I think both of you, you and Mriana, are running out of questions.
I feel like my intelligence was just insulted.That's how I felt when I asked MacGeyver what an "average diet" was. He then proceeded to explain that an "average diet" was what the average diet was of all participants in a controlled study. What study? What were they studying? You test adolescents, who are allegedly vegan for ethical reasons and not for other reasons, it seems to me researches need R/O an eating disorder before proceeding to include the children in the study. These children could be deficient due to an eating disorder and not due to a vegan diet. Run it on adults who are not only vegan for ethical reasons, but also try to stay healthy on a vegan diet, which means, they will get iron from dark green veggies such as spinach and broccoli. They will get calcium from things like tofu and soy milk. If they do it right then they shouldn't be deficient in iron and calcium. Vitamin D on the other hand, even omnivores can be deficient in that, esp if they don't get enough sun, because there are very few foods that have vitamin D. Not only that, some omnivore adults avoid milk because, like my grandfather, believe that once a person is weaned, they don't need milk any more, there by causing themselves to potentially be calcium deficient and maybe even lack vitamin D. Mushroom, from what I read on a package last summer, allegedly have 100% vitamin D, but there again, not even vegans eat them every day, much less meat and potato lovers. So IMHO, the study had no validity.
There are a fair number of RCT's that look at the affect of vitamins on mortality but most of them are in patients with specific disease like cancer and heart disease. The primary reason is that the longer the life expectancy of the participants the longer it takes to do the study. Longer studies also have higher rates of participant dropout and are more expensive to do. Obviously people suffering from heart disease and cancer don't have long life expectancies so they are easier to study. These patients also have more to gain if a beneficial effect is found.:lol: Where do I start with this one? Seriously Macgyver, you're telling us, the vitamins killed the patients in such studies with cancer and heart patients? Not only that, you cannot test to see if a supplement prevents or lowers the risk of a disease if they all ready have that disease.
You are a strange man, VYAZMA.What makes you say that George, if you don't mind me asking? Because you are asking strange questions. I don't think macgyver could be any clearer. I know you are trying hard to find something wrong with what he's saying, but I think both of you, you and Mriana, are running out of questions. I just started and the vegan question was probably only my second one, of which he chose a study of teenagers who go, "Oh potato chips! They're made out of potatoes, so no animals died from this. Chomp chomp chomp I ate the whole bag."
There are a fair number of RCT's that look at the affect of vitamins on mortality but most of them are in patients with specific disease like cancer and heart disease. The primary reason is that the longer the life expectancy of the participants the longer it takes to do the study. Longer studies also have higher rates of participant dropout and are more expensive to do. Obviously people suffering from heart disease and cancer don't have long life expectancies so they are easier to study. These patients also have more to gain if a beneficial effect is found.:lol: Where do I start with this one? Seriously Macgyver, you're telling us, the vitamins killed the patients in such studies with cancer and heart patients? Not only that, you cannot test to see if a supplement prevents or lowers the risk of a disease if they all ready have that disease. Mriana please read what I wrote. I did not say the vitamins killed the patients. If you read my post I did not discuss the results of those particular studies, I was just describing how and why they are done. Secondly the purpose of that type of study is not to prevent the disease in a patient who already has it. The purpose is to see if you could improve the outcome by prolonging life or reducing death rates.
There are a fair number of RCT's that look at the affect of vitamins on mortality but most of them are in patients with specific disease like cancer and heart disease. The primary reason is that the longer the life expectancy of the participants the longer it takes to do the study. Longer studies also have higher rates of participant dropout and are more expensive to do. Obviously people suffering from heart disease and cancer don't have long life expectancies so they are easier to study. These patients also have more to gain if a beneficial effect is found.:lol: Where do I start with this one? Seriously Macgyver, you're telling us, the vitamins killed the patients in such studies with cancer and heart patients? Not only that, you cannot test to see if a supplement prevents or lowers the risk of a disease if they all ready have that disease. Mriana please read what I wrote. I did not say the vitamins killed the patients. If you read my post I did not discuss the results of those particular studies, I was just describing how and why they are done. Secondly the purpose of that type of study is not to prevent the disease in a patient who already has it. The purpose is to see if you could improve the outcome by prolonging life or reducing death rates. I don't think vitamins can improve the outcome, not by much at least, after one already has the disease. I think if they want to test that, then maybe they ought to try testing Eastern medicines and even American Indian medicines, for a change. From my understanding, esp American Indian medicine, researchers haven't thoroughly researched or they've suppressed any research done on them, which they've done since at least the 1800s.
d are more expensive to do. Obviously people suffering from heart disease and cancer don't have long life expectancies so they are easier to study. I think if they want to test that, then maybe they ought to try testing Eastern medicines and even American Indian medicines, for a change. From my understanding, esp American Indian medicine, researchers haven't thoroughly researched or they've suppressed any research done on them, which they've done since at least the 1800s.You sound like you have been reading a Kevin Trudeau book. No, claims are investigated. We have synthesized many drugs which were originally 'natural' cures, once they were found to be effective. By synthesizing the active ingredient, we can control the dosing strength and purity. It would be stupid to 'suppress' research on possibly helpful cures.