Monday, July 22, 2013

Stop Taking Vitamin Supplements!

Here's a post for all my friends and acquaintances who think they have to load up on vitamin supplements ever day. You don't need them (unless you are ill or pregnant).

If you think you do, then chances are you've fallen victim to one of the biggest scams of modern times. It's not much different than the pitches made by snake oil salesmen over one hundred years ago. There are people making big money by convincing gullible citizens that they have vitamin deficiencies. Some of those people are doctors and many of the enablers are family physicians who don't know the scientific evidence behind vitamin supplements.

"There's a sucker born every minute."

David Hannum
(frequently attributed to P.T. Barnum)
The Atlantic has published a nice summary of the current evidence: The Vitamin Myth: Why We Think We Need Supplements. Most of the article is about Linus Pauling and why he was spectacularly wrong about vitamin supplements. Here's the bottom line ...
On October 10, 2011, researchers from the University of Minnesota found that women who took supplemental multivitamins died at rates higher than those who didn't. Two days later, researchers from the Cleveland Clinic found that men who took vitamin E had an increased risk of prostate cancer. "It's been a tough week for vitamins," said Carrie Gann of ABC News.

These findings weren't new. Seven previous studies had already shown that vitamins increased the risk of cancer and heart disease and shortened lives. Still, in 2012, more than half of all Americans took some form of vitamin supplements.
I'm not convinced that moderate amounts of vitamin supplements will actually cause you much harm—the jury's still out on that IMHO. However, it's now abundantly clear that, for the average healthy person, spending money on vitamin supplements is no different that flushing that money down the toilet, which, coincidentally, is where most of the vitamins you take will eventually end up.

See also: What Kind of People Take Vitamins?.


11 comments :

  1. What about non-vitamin supplements, like calcium, omega-3, etc.?

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    Replies
    1. Same advice. You don't need calcium unless you are ill, pregnant, or elderly. Omega-3 is just a scam. You get plenty of essential fatty acids in your food and taking more omega-3 will not make you smarter.

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    2. "You get plenty of essential fatty acids in your food..." How could you possibly know this statement applies to all your readers? Isn't the point of supplements, at least in part, to compensate for those who do not have the sort of diet you appear to assume they do? I take Omega-3 to help manage my cholesterol levels because my physician recommended I do so on the basis of my labs and discussion of my diet. I certainly wouldn't need it if I ate other good sources of essential fatty acids, but this is not the case.

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    3. I'm well aware of the fact that some people may benefit from some supplements.

      However, in the case of omega-3 fatty acids, there's very little scientific evidence to support the idea that extra supplements have any effect whatsoever. That doesn't stop some people from making extraordinary claims [Smart Crocodile Eaters?] [Good Food, Bad Food].

      The possible benefits of omega-3 fatty acids on cardiovascular disease (CDV) are debated within the scientific community, which means there's no proof. Here's what two experts had to say last year in: Omega-3 Fatty Acids and Secondary Prevention of Cardiovascular Disease—Is It Just a Fish Tale?.

      While waiting for more definitive results, what should physicians tell their patients? To date, there is no conclusive evidence to recommend fish oil supplementation for primary or secondary prevention of CVD.

      Those physician-scientists go on to say that a healthy diet should include fish and vegetables because they are rich in omega-3 fatty acids.

      Are you aware of the fact that many physicians are not on top of the scientific literature? I recommend a second opinion unless you are one of those rare individuals who can't eat vegetables.

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  2. From The Atlantic article.

    "Whatever the reason, the data are clear: high doses of vitamins and supplements increase the risk of heart disease and cancer."

    Based on the article, all the data are correlational and so that interpretation of the data can't be supported.

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    Replies
    1. All data is correlated to phenomena. We correlate the smashings of heads through windshields with the loss of life. The only difference is the strength of the correlations and whether we think we have a good understanding of how/why they (the data and the phenomenon) correlate.

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    2. "We correlate the smashings of heads through windshields with the loss of life."

      The correlation is irrelevant and comparison trivial because we have a clearly delineated cause and effect with severe head trauma and loss of life. The reasons are not anywhere as clear, based on the article at least, as to why high doses of vitamins increase cancer risks.


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    3. Actually, there are good biochemical reasons to think that high doses of vitamins and other nutrients will do damage. They are speculative reasons, but such negative results are not surprising outcomes to academic biochemists who see some reasons to expect bad results.

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  3. The problem with observational studies is that people who take multivitamins are different in many ways from people who don't, and you can't mathematically control for everything, especially things you didn't measure. The only study to investigate this question in a compelling manner was the Physician's Health Study randomized controlled trial. Centrum Silver multivitamin vs placebo. After 11.2 years of follow-up, the cancer rate in the multivitamin group was 8% lower. The effect is very small, but at least it shows that cancer risk doesn't go up.

    http://jama.jamanetwork.com/article.aspx?articleid=1380451

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  4. Some recent study implicated high serum levels of omega-3 fatty acids with increased risk of prostate cancer.

    On the other hand, there is this controlled study on the benefits of B6, B12 and folic acid, regarding Alzheimer's:

    http://www.digitaljournal.com/article/350537

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  5. My doctors always told me one didn't need vitamine supplements. A good diet did the trick.
    It also makes sense since so many peoples in the past in many places couldn't of had much vitamine intake. Yet were healthy. Northern Europeans wre not eating oranges. Indeed we were white in order to increase the effect of the sun for vitamines but that did the trick.
    I suspect they are a minor part of health.

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