Do vitamins work?
January 25, 2010 5:03 PM   Subscribe

Do vitamins work?

My boyfriend and I argue about this all the time. He claims that vitamins boost his immune system and "make him healthier"; I say that I don't think that most vitamins are absorbed properly by the body when they're not in real food (i.e., blueberries, collard greens) and are a waste of money. Neither of us really knows all that much about nutrition other than the pop pseudo-scientific stuff that saturates the web, yet we're both respectively convinced that we're right. I right? Is he right? Are we both sorta right? Or is there not really any way to scientifically prove anything about vitamins' efficacy?
posted by duvatney to Health & Fitness (46 answers total) 29 users marked this as a favorite
If you have a vitamin deficiency then vitamins in pill form will absolutely get absorbed and cure the issue. Do either of you have a vitamin deficiency?
posted by GuyZero at 5:08 PM on January 25, 2010

On the other side of the coin, if you don't have a vitamin deficiency, vitamins will have no noticeable effect on you unless you overdose on them, which can cause problems.
posted by Chocolate Pickle at 5:10 PM on January 25, 2010

Response by poster: I don't think so. Generally speaking, we're both pretty healthy--non-smokers, vegetarians (though we eat fish) and regular gym-goers. I very rarely get sick; I'll maybe have a mild cold one or two days a year. He came down with a nasty spell of bronchitis last year that lasted for weeks, but, to his credit, he claimed this was highly unusual.
posted by duvatney at 5:13 PM on January 25, 2010

If he eats well, then he probably has no need for vitamins. I guess there could be an issue with vitamin absorbtion but he would have more serious issues than just a lack of energy, at least over the long haul.

Too many vitamins can mean a problem with your body getting rid of excess minerals, which could lead to kidney stones. Excess A, D, or E are toxic too. Although to reach those levels he would have to be taking a megadose. A regular multivitamin a day probably doesnt hurt, especially if his diet is poor.
posted by damn dirty ape at 5:14 PM on January 25, 2010

There are a huge, huge, huge number of studies which compare an experimental group taking a nutritional supplement to a control group taking a placebo instead. A reasonably large number of these studies find statistically significant differences between the control group and the experimental group.

For example, taking a folic acid supplement will reduces the odds birth defects, even in women in the developed world who have apparently sufficient diets otherwise. Is your dispute that folic acid supplements doesn't qualify as a "vitamin", or do you dispute the validity of the scientific studies which validate this cause->effect relationship?
posted by 0xFCAF at 5:17 PM on January 25, 2010 [2 favorites]

Wow, I mangled that one. "will reduce the odds of birth defects". I can has live edit?
posted by 0xFCAF at 5:18 PM on January 25, 2010

Best answer: It's nearly impossible to determine whether any lifestyle choice (such as taking vitamin supplements) "makes you healthier". Studies that attempt to address that sort of question are epidemiological studies, and they are notorious amongst scientific studies for being difficult to interpret due to massive unknowable sets of uncontrolled variables. These studies are also notorious for being widely misinterpreted.

Nonetheless, if you want some science, There is a 2008 metastudy (by which I mean a study that attempts to draw more accurate conclusions by analyzing a large set of previous studies) which suggests that vitamin supplements are linked to an overall higher mortality. I.e. no, they don't make you healthier, and might even decrease your overall lifespan. Maybe. Or maybe not.

My personal opinion is that there is no wisdom that has held the test of time like "fruits and vegetables are good for you". Vitamin supplements? Who knows. Supplements certainly aren't a source of vitamins which our bodies evolved to absorb correctly or in the right amounts. In short, I think multivitamin pills are pretty silly, and probably useless, as well as possibly unhealthy in moderate to large amounts. Specific vitamin supplements for specific purposes are probably fine, but there are usually better, more healthy ways.

(small nitpick - vitamins are absolutely necessary to remain alive. Vitamin supplements? Not so much.)
posted by Salvor Hardin at 5:18 PM on January 25, 2010 [4 favorites]


And as it turns out, antioxidant supplements appear to cancel out many of the beneficial effects of exercise.

And then there's "not only do vitamin supplements not protect against gastro-intestinal cancer, they may slightly increase the risk of cancer" ...

Other supplements are as useless, for example ginko biloba is widely touted as preventing the decline of memory, etc: Millions of people take vitamin supplements and among the most popular is ginkgo biloba, with a reputation for boosting concentration, memory and even thwarting dementia. But the popular herb has been proven to do none of those things.

Ditto B12, etc. claims.

There is no positive evidence for vitamins where a deficiency is not present with possibly the exception of vitamin D and there is basically zero chance that you are vitamin deficient in context.
posted by rr at 5:21 PM on January 25, 2010

Response by poster: 0xFCAF, I hadn't considered folic acid (since neither of us are pregnant women), but thanks for letting me know of its benefits. I suppose my position (again, an intuitive and uninformed one) is that there is no need to take a multivitamin if your diet is well-balanced and contains plenty of fresh fruits, vegetables, nuts, etc.

On preview, I see a lot of links. Can't wait to check them out!
posted by duvatney at 5:23 PM on January 25, 2010

PS: Since you mention that you're vegetarians, it is often recommended that vegetarians take a small B12 supplement. Omnivores are less likely to be B12 deficient because they eat meat which gets mixed up with animal shit, which has plenty of B12. It's certainly not necessary for most vegetarians, but it might be a good idea, since the rare case of B12 deficiency can cause a lot of bad problems.

Or, another example, menstruating women can become anemic, which can be alleviated with iron supplements. However, there are probably healthier ways to get more iron (dark leafy green vegetables, for instance).
posted by Salvor Hardin at 5:23 PM on January 25, 2010

there is no need to take a multivitamin if your diet is well-balanced and contains plenty of fresh fruits, vegetables, nuts, etc.

IMO, this philosophy will serve you very well.
posted by Salvor Hardin at 5:24 PM on January 25, 2010

Best answer: What everyone else said.

Also: From a nutritional standpoint, it's actually pretty unlikely that you're getting 100% the RDA of every nutrient from your diet alone. Most people don't get an adequate intake of vitamin E, vitamin D, or omega-3 fatty acids (just to name the three that pop into my mind). Additionally, a lot of vegans are at risk for vitamin B12 deficiency. There's some evidence that the bioavailability of some vitamins is higher when they are in certain foods, but that coin has two sides too: your calcium and iron supplement might be more bioavailable than the calcium and iron in your collard greens.

What I did was to go to and track my diet for a couple weeks, then look at long-term trends. Turned out that I was good on a lot of vitamins, but short on vitamin E, vitamin D, a couple B-complex vitamins, and a few minerals. I went with a multivitamin that contained everything that I was likely to be deficient in, plus an omega-3 fatty acid supplement. I haven't noticed any extra bounce in my step, but then again I haven't gotten sick at all since I started taking them in November, and I had several wicked colds in September and October (yes, yes, correlation does not equal causation, but it's a data point).

The stuff that I'm fairly skeptical about is stuff like antioxidant supplements -- for compounds that are thought to be beneficial, are enriched in various plants and vegetables, but isn't actually known to be required for the correct functioning of your cells, I would rather munch a tasty blueberry than take a pill full of an extract from a blueberry, which may or may not contain the chemical actually responsible for the positive health effect of blueberries. But the data on actual vitamins, as well as (I at least think) the data on omega-3 fatty acids, is pretty solid. I would also consider vitamin D supplementation -- the current RDA is 400 IU/day, but there are some suggestions that people should get more like 800-1000 IU/day for improved insulin sensitivity, lowered risk of hypertension, and healthy immune function (run a quick Pubmed search).

I would be more concerned about overdosing on fat-soluble vitamins rather than water-soluble ones. You can eat as much vitamin C as you want, and your kidneys will just pee it all out again. But eat too much of the fat-soluble stuff and you can poison yourself (for example, the upper limit for safe vitamin D intake is just 2000 IU per day (though it might get raised to 10,000 IU), which is only twice what some nutritionists recommend for daily intake!
posted by kataclysm at 5:30 PM on January 25, 2010 [2 favorites]

According to this journal article, multivitamin use is associated with longer telomeres. I don't know enough about the American Journal of Clinical Nutrition to say whether it's an important study or not, though.
posted by you're a kitty! at 5:32 PM on January 25, 2010

Response by poster: Sorry, you're a kitty, but I don't know what a telomere is. Nor do I know if a longer one is a good thing, a bad thing, or a cataclysmically bad thing!
posted by duvatney at 5:34 PM on January 25, 2010

re: the folic acid thing

If you wait to supplement with folic acid until you know you're a pregnant woman, you won't do your fetus any good. Folic acid is important in neural tube formation, which happens early in the first trimester of pregnancy (third week of gestation, i.e. before a lot of women know they're pregnant). This is why most physicians recommend that if a woman is planning a pregnancy, that she should start taking prenatal vitamins before the baby is conceived.

Basically, my philosophy on dietary supplementation is not to eat stuff that you don't need to be eating, but that it probably won't hurt to eat stuff that you're lacking (especially stuff like vitamin D, vitamin E, and omega-3 fatty acids, which are all basically impossible to obtain adequate dietary levels of without risking mercury poisoning [E, omega-3's] or skin cancer [D].) The trick is to know what you're likely to be lacking, and that's going to be different for everyone depending on their diet's overall quality.
posted by kataclysm at 5:37 PM on January 25, 2010

Best answer: I'm not sure if your admittedly pseudo-scientific explanation about vitamins in pills not being "absorbed properly" is right. But you're right to be skeptical of the ability of vitamin pills to take the place of the health benefits in real food.

Taking vitamins C and E supplements doesn't reduce the risk of heart disease or cancer.

Vitamin supplements may wipe out the benefits of exercise, unlike plants that naturally contain the same vitamins. (On preview, rr beat me to it.)

From an interview with Michael Pollan:
[Q:] Then there's this idea that food is something you can endlessly fragment: if you find something in a food that's beneficial, you can isolate it, and concentrate it, and put it in a pill.

[Pollan:] It's the reductionist's logic of food science, basically. And the interesting thing is that whenever that has been tried, it has failed. Foods are much more than the sum of their nutrient parts, and you cannot expect to get the same effect. Now there are things like vitamins that have been isolated, and in their isolated form they can cure deficiency diseases. But when they've tried to take out the antioxidants, things like beta-carotene and vitamin E, they don't seem to work.

[Q:] There's an analogy there with agriculture: the macronutrients in food and the macronutrients in soil. A, B, C, and D vs. N, P, and K. Turns out that soil needs more than just isolated N, P, and K to produce fully nutritious food.

[Pollan:] There's a mystery at both ends of the food chain. There's the mystery about what makes a healthy soil, which you cannot yet fake or simulate, and there's the mystery of what makes a healthy food, which you cannot yet simulate or fake.
posted by Jaltcoh at 5:38 PM on January 25, 2010 [2 favorites]

A longer telomere is a good thing. Telomeres are basically the raggedy ends of your DNA, which get shorter the more times a cell divides. It's thought that a telomere might act like a cellular clock that tells your cells how old they are, and therefore they might contribute to aging.
posted by kataclysm at 5:38 PM on January 25, 2010

rr, do you dispute that folic acid supplements reduce the risk of birth defects? A study published by Milunski et al. has indicated that women who took folic acid supplements during the course of pregnancy can dramatically reduce the prevalence of infant neural tube defects by 3.9 times. The prevalence had dropped from 3.5 to 0.9 defects per 1000 births

No. And you're relying on an example that is based on a deficiency and which the response is to put the entire population at (apparnt) risk. The issue with folic acid is that the western diet of processed foods, mostly refined grains, created a vitamin deficiency.

This is not a strong example for vitamin advocates.
posted by rr at 5:44 PM on January 25, 2010

a lot of vegans are at risk for vitamin B12 deficiency.

They said they're vegetarians; they didn't say they're vegans. Vegetarians can get vitamin B12 from dairy and eggs. Even vegans can get vitamin B12 from certain food products such as veggie burgers.

But actually, they said they're vegetarians who eat fish. So, they're better described as pescetarians. Fish and seafood have vitamin B12.

It's not surprising that when the words "vegetarian" and "vitamin" appear together in a question, some of the answers warn about B12 deficiency. This is because there are so few nutritional deficiencies that people actually have to worry about based on being vegetarians, so B12 stands out as a concern. It's a valid concern, but one that can be addressed without vitamin pills. A fish-eating vegetarian (pescetarian) has lots of different opportunities to get vitamin B12 by eating real food.
posted by Jaltcoh at 5:46 PM on January 25, 2010

Best answer: It's pretty easy to say "vitamins don't work, I eat healthy so I'm okay" when you live in a society in which doctors have figured out which deficiencies naturally occur in the population and started campaigns to fortify the food supply with vitamins to eliminate those deficiencies. If we lived in a society where people taking iodine supplements were conspicuously missing swollen thyroid glands, you'd probably be a lot easier to convince.

What this really comes down to is: Do you believe science works?

If you believe science works, you can recognize that despite having an otherwise healthy diet (remember that fortification has fixed some aspects of your diet already, without you even knowing it), it's possible that there are deficiencies which can cause health effects which aren't immediately apparent. Examples like folic acid supplementation reducing the risk of birth defects, fluoridation reducing the risk of cavities, iodine fortification reducing the prevalence of goiter, iron supplements reducing the risk of anemia, etc are all statistically validated effects of vitamins. Double-blind experiments and epidemiological studies are the tools of nutritional scientists and they regularly publish research which indicates that vitamin supplements can have positive (and negative!) effects on health. Just do an interwebs search for "double blind study [nutrient name]" and start reading journal abstracts.

If you don't believe science works, you can just ignore all these studies and say "Huh, well, I eat pretty well and feel fine, so I must be getting enough zinc, B12, creatine, vitamin D, iron, iodine, ..." even though the effects of these deficiencies are easy to miss, can be mistaken for other things, or will only cause problems long down the road.

On the other hand, you can't just slam down 15 pills a day without doing the right research and expect this is going to improve your health. I live in a northern (i.e. dark) climate and don't get outside enough in the winter, so I take a vitamin D supplement because this is epidemiologically shown to be beneficial. I stop taking it in the summer when I'm out for 5+ hour bike rides every weekend. Vitamins work, but Centrum isn't a substitute for a healthy diet.

This is not a strong example for vitamin advocates.

The question wasn't "Is folic acid fortification a good idea?", it's "Do vitamins work?". Folic acid fortification causing something to happen, even if it has negative side effects, is incontrovertible evidence for "yes".
posted by 0xFCAF at 5:49 PM on January 25, 2010 [7 favorites]

My advice is general, but if you're researching this, never rely on mainstream media summaries of academic articles in medical journals. They almost always get it wrong. Always go to the original article.
posted by demiurge at 5:52 PM on January 25, 2010

Best answer: You might know this, but in case you don't: there are two kinds of iron - heme and non-heme. Heme comes in animal protein and our bodies uptake it well. Non-heme iron is found in plants, and is more difficult for our bodies to uptake. Cook your spinach in a cast iron pan, or squeeze some fresh lemon juice on that broccoli (citrus increases non-heme iron uptake). Since you eat fish, you get iron there, too. But you especially, as a woman, should keep an eye on your iron levels - it's easier to become, and remain, mildly anemic without really knowing that that's what's making you feel so tired etc.

Anyway. More here.
posted by rtha at 5:52 PM on January 25, 2010 [3 favorites]

My (clearly less well-researched) understanding is that vitamins from food are a HELL of a lot better absorbed. But from my personal experience, I can tell you if you have a deficiency supplementation does work. I take an iron supplement called Hema-Plex. It is the only thing that keeps me from being borderline anemic (and I eat quite a bit of meat). I started taking it on recommendation from a Red Cross nurse who suggested it after I was turned away from donating blood yet again for having too low iron. Two weeks on it and bam, my levels were healthy again, with no dietary changes on my part. Clearly some supplementation, if the vitamin is a good one (not all supplements are created or absorbed equally) can be useful. I've found ZMA, magnesium citrate supplements like Natural Calm, and fish oil to all have clear effects on my health, though I've not been able to measure it as clearly as having a nurse take my iron levels.

You want to watch out on megadosing on fat-soluble vitamins (like A or D or E as mentioned earlier)--the water-soluble ones you can urinate out, the fat-soluble ones won't.
posted by Anonymous at 5:53 PM on January 25, 2010

Ok Jaltcoh, so maybe they aren't at risk for B12 deficiency. I would say that they are still very likely to be at risk for deficiencies in vitamin D, as well as an improper omega-3:omega-6 fatty acid ratio. It is nearly impossible to get adequate vitamin D in your diet without supplementation, unless you are willing to put yourself at risk for skin cancer by forgoing sunscreen. Similarly, it is almost impossible to eat a proper ratio of omega-3 FA to omega-6 FA without resorting to supplementation, unless you are willing to be SUCH a pescetarian that you eat enough fatty fish to give yourself mercury poisoning. (The average American diet is something like a 20:1 ratio of omega-6 to omega-3. The optimal ratio is currently thought to be somewhere between 4:1 and 2:1. Granted, a pescetarian couple that eats a balanced diet is leaps and bounds above the rest of the herd, but I would guess that if they ever cook with canola oil, they probably need to be eating some more omega-3's to balance it out.)

In principle, I agree with you -- most people should be able to get most of the nutrients that they need by eating a well-balanced diet. But there's always going to be something that people are deficient in. I don't advocate taking random unnecessary supplements (I only take the multi-v because it's a hell of a lot cheaper than buying separate bottles of each vitamin or mineral that I need, and I think the overall risk of poisoning myself is fairly low.) But I do think that, even if you're a Michael Pollan-reading, well-fed foodie, you're probably deluding yourself if you think the quality of your nutrition is so good that it can't be improved upon by well-chosen supplementation.
posted by kataclysm at 5:56 PM on January 25, 2010 [3 favorites]

Vitamin B12 is mentioned above. You need 2-3 micrograms per day, which you can get from margarine, breakfast cereals, soy milk, and of course the fish you eat. That said, I take a multi-vitamin with a totally ridiculous number of ingredients and coverage for water-soluble vitamins, and believe I feel better when I do (which is totally unscientific, but works for me).
posted by Houstonian at 6:01 PM on January 25, 2010

Response by poster: 0xFCAF, thanks again for your expertise. I hadn't really thought about common fortifications like iodine, iron, fluoride, etc., and I don't dispute their generally positive effects, though you did jar a memory of their potential downside: when my (much younger) brother was a small child, we weren't allowed to give him tap water, because the fluoride levels in our town's water were too high and there was a bit of a fluorosis outbreak in its small children (however, I am relying upon a 15-year-old memory here, so I can't back this up with an article or anything).

I suppose I hadn't thought before about how many different types of vitamins there are. I now think my general skepticism, most of which is provoked by multivitamins and supplements such as Airborne and Acai berry extract and such things, should perhaps not be directed at all vitamins in pill form. But I am still not exactly a convert.

rtha, thanks! I have a much-used cast-iron pan, in which Swiss chard shall soon be cooked!
posted by duvatney at 6:13 PM on January 25, 2010

Do either of you have a vitamin deficiency?

That's really the question. And I would suggest that quite a few people are deficient in at least one vitally important vitamin: Vitamin D (cholecalciferol, specifically). If you work in an office, drive to work and wear clothing all day like most people, you need hours of UVB exposure for your body to build up any appreciable amounts of vitamin D. If you have dark skin or live north of 35° latitude, you can forget about it. And the minuscule amounts added to milk and orange juice are woefully insufficient (and are typically vitamin D2, which isn't the same). Vitamin D is molecularly rather neat in that it's a prohormone used by the body for all kinds of helpful things like calcium absorption, helping the immune system, preventing cardiovascular disease, not to mention its anti-cancer effects.
posted by Civil_Disobedient at 6:16 PM on January 25, 2010 [1 favorite]

While there's certainly a ton of crap being sold to people who don't need it via dubious claims, it's not all worthless. Vitamin D, C, B12, and fish oil are in the probably help, won't hurt category.
posted by Mr. Gunn at 6:27 PM on January 25, 2010

My uncle, a psychiatrist, says that Vitamin D and Omega-3 are the only dietary supplements that have shown any positive effects in clinical studies.
posted by eggplantplacebo at 6:55 PM on January 25, 2010

The question wasn't "Is folic acid fortification a good idea?", it's "Do vitamins work?". Folic acid fortification causing something to happen, even if it has negative side effects, is incontrovertible evidence for "yes".

Oh good grief. Her question wasn't "is there a specific case where a vitamin has helped due to induced deficiency" it was about her goofball boyfriend popping vitamins because they "vitamins boost his immune system."

There is no deficiency question here, it is your standard supplementer. FFS, this is not about "science." There is plenty of science (above) that cases like we're discussing are of zero _or negative_ benefit.
posted by rr at 7:16 PM on January 25, 2010 [3 favorites]

I think Michael Pollan has many interesting things to say, and he says them well, but for me, Michael Pollan is not an authority on nutrition - he just isn't. He's a writer, who has done some research and has a point of view.

In my opinion, the vast majority of people do not have the time/energy/resources to eat a balanced diet all of the time.

A multivitamin, additional vitamin D and an omega 3 supplement make sense - and an eye towards what's being studied and written about by people actually doing research.
posted by nnk at 7:21 PM on January 25, 2010

that's a little unclear. Michael Pollan has done some reading and he writes about what he has read.

Scientist who publish in reviewed journals have done primary research the results of which they write about.
posted by nnk at 7:24 PM on January 25, 2010

I now think my general skepticism, most of which is provoked by multivitamins and supplements such as Airborne and Acai berry extract and such things, should perhaps not be directed at all vitamins in pill form.

As far as I know, a daily multivitamin and Airborne are basically the same thing, just marketed for different purposes - one legit ("if you're not getting enough of these vitamins, here's a concentrated form"), and one resulting in a class-action lawsuit.

It sounds like your boyfriend buys into the latter argument, which is not in fact based on science, and I think that's what you were really asking. As to whether you should be taking a multivitamin every day, the answer (as it so often is in medicine) seems to be that, well, "it depends."
posted by you're a kitty! at 7:52 PM on January 25, 2010

duvatney: “He claims that vitamins boost his immune system and "make him healthier"...”

There's already a huge lot of info here, so just a small point:

There's a wide urban legend that vitamin C will "boost the immune system." This urban legend has be perpetuated by such products as "Airborne." This is in fact utterly false; it was a belief of Linus Pauling, who was a rabid booster of the stuff and claimed to take 10,000 mg (!) of it every day, saying it would cure everything from cancer to the common cold. It's been known that vitamin C neither cures nor prevents any form of common cold, for example, since 1976. We also know that it has no effect on cancer, and that it causes no apparent change in the immune system whatsoever, so any claim that vitamin C "boosts the immune system" has no basis in fact. It is, however, a mild energy booster.

This is a big one for me, at least, because sometimes it seems like almost everybody is under the false impression that vitamin C can "boost their immune system." You'll often hear this: "there's a cold going around; you should take some vitamin C so you don't get it!" I always reply that I'd be just as well drinking a can of Coke or something; vitamin C has absolutely nothing to do with the immune system.
posted by koeselitz at 8:30 PM on January 25, 2010 [1 favorite]

I used to take vitamen supplements until a plumber told me whenever they swap out old septic tanks they find many vitamin pills inside them. So perhaps the unasked question is,
Are vitamin pills digested?
posted by Rash at 9:03 PM on January 25, 2010

Are vitamin pills digested?

I'm surprised no one brought that up yet. Some companies use machines that crush the hell out of pills, for a longer shelf life, and they don't digest at all.
posted by P.o.B. at 9:20 PM on January 25, 2010

Best answer: Basically, in short, no two people agree about this even a little bit. There is no unquestionably reliable information. Flip a coin. You're welcome.
posted by paultopia at 9:50 PM on January 25, 2010 [1 favorite]

rr, Jaltcoh -- It seems that the article ya'll linked to about antioxidants 'negating the effects of exercise' was only really concerned with their effects on one's insulin resistance. Please correct me if I'm missing something, but it seems that the articles' headlines (and your links) are grossly exaggerated claims.
posted by JohnFredra at 9:51 PM on January 25, 2010

Best answer: Medline Plus has detailed information on many common vitamins and supplements, and grades each of them on how well they've been proven to address a number of health issues.

Unsurprisingly, the most common grade is "C - Unclear scientific evidence for this use;" the "A"s mostly just reveal that a given vitamin tends to be pretty good at treating a deficiency of that given vitamin. A "C" grade of course doesn't mean that the vitamin/supplement doesn't effectively treat the disorder in question - it just means it hasn't been proven one way or the other.

There is some interesting stuff, though. Besides the alert-the-media news that Vitamin C treats scurvy, the site also claims that there's "Good Scientific Evidence" for it helping with iron absorption and UTI-prevention during pregnancy. And though there's "Fair Scientific Evidence Against" C's effectiveness in preventing and treating the common cold under normal conditions, in extreme conditions (like sub-Arctic temperatures) it does seem to work. Zinc seems pretty good at treating gastric ulcers, sickle-cell anemia, diarrhea in malnourished children, some ADHD symptoms, high cholesterol, and herpes; it also helps with immune function. St. John's Wort gets a straight-up "A" for treating mild to moderate depression. And so on.

So, I think a fair answer to your question is: Yes. No. It depends. We don't know.
posted by granted at 12:43 AM on January 26, 2010 [2 favorites]

My sister was highly deficient in Vitamin D; my mom in B12; me, I need iron and folic acid. All of these things were diagnosed by a doctor, treated by a doctor, and we all feel a lot better when we're getting our vitamins (my mom gets a shot; my sister gets a shot and takes pills; i take folic acid every day, and iron periodically). We all felt crappy enough without the vitamins to go to the doctor. So, ask your doctor, especially if you are feeling generally crappy.
posted by dpx.mfx at 6:42 AM on January 26, 2010

Everyone has brought up the vitamin D thing already, but I want to emphasize that the likelihood of being deficient in this has almost everything to do with where you live and what time of year it is.

Here in San Diego, it would be a BAD idea for me to take vitamin D supplements in summer, when I get strong UV from only a few minutes outside with my fair skin, even with sunscreen on a few spots. My skin naturally will not produce more vitamin D than my body can safely use, but if I keep adding 2000 iu in supplements, not only am I wasting the supplement because my body can't use it, but it may cause unknown harm. In the winter, I may be slightly deficient, but a paper I read (on Pubmed, not publicly accessible) says that we are close enough to the equator that I can get enough UV year-round by varying my time outside.

However, if you're living north of 35 degrees latitude, like say, Boston, you are almost certainly deficient for at least part of the year without supplements. There is not enough UV for at least 4 months out of the year for your skin to make vitamin D, and so you need 100% from diet. There is a tentative hypothesis that the seasonal rise in blood pressure is linked to winter vitamin D deficiency, but it's not rock-solid. Still, couldn't hurt to take a moderate dose of the supplement in that context.

I go into all this detail just to show that your individual circumstances, like your medical history, biochemistry, diet, exercise, and even where you live will determine if certain supplements are more in the "probably overkill" or "couldn't hurt" category for you.
posted by slow graffiti at 9:20 AM on January 26, 2010

Here's some more detailed info for vegetarians about how to get enough iron. It seems feasible but also pretty elaborate: it's not just about heme vs. non-heme iron, but also eating them along with the right foods. (For instance, iron-rich vegetarian foods along with coffee or tea -- bad; along with orange juice -- good.) As rtha noted, pre-menopausal women (you) need more iron than men.
posted by Jaltcoh at 10:10 AM on January 26, 2010

A small side rant: Whether or not you observe cold symptoms does not mean a damn thing about how healthy your immune system is (w exceptions for large studies).

Most of the cluster of symptoms we call a "cold" (runny nose, low energy, stuffiness) IS your immune system working. So, if you have an immune system that is running at 100% and making lots of interleukins, you may fight off a virus successfully but get terrible cold symptoms as a consequence. If supplements "boosted your immune system" you could alternate between seeing no symptoms for viruses you have seen before due to humoral immunity, and feeling like you were run over by a truck when you are infected by a novel pathogen.
posted by benzenedream at 4:50 PM on January 26, 2010 [1 favorite]

« Older What is the maximum amount of memory (RAM) I can...   |   Make Up Your Mind! Newer »
This thread is closed to new comments.