These articles appear every few years and attract attention because they claim that multivitamin supplement takers might actually be harming themselves. Fear sells. Actually, there has never been a single death anywhere in the world attributed to a multivitamin. So let’s right size this. Firstly, it refers to four studies pooling the results of other studies (always a dodgy thing to do unless the studies were testing the same thing and giving the same nutrients, which they weren’t) giving multivitamins that did nothing. I know these studies inside out and have dissected them in previous articles.
The first study, published by the Agency for Healthcare Research and Quality in 2006, concludes “Multivitamin/mineral supplement use may prevent cancer in individuals with poor or suboptimal nutritional status.” The article concludes that therefore multivitamins do nothing, except in developing countries, as if it is only there that people have suboptimal nutritional status. Really?
The second one, published in Archives of Internal Medicine in 2009, does conclude that there’s no convincing evidence that multivitamin use has little or no influence on the risk of common cancers, CVD, or total mortality in postmenopausal women’. However, what this article fails to point out is that, in a sub group who were taking higher doses (often >200% of US RDA – which is what I recommend) of several B vitamins and often including large doses of vitamin C or selected minerals, such as selenium or zinc there was a 25% decreased risk of having a heart attack.
The third links to an article in the Daily Mail, apparently referring to a French study showing no benefit from taking multivitamins. I’ve searched for this study, apparently in the International Journal of Epidemiology in 2010 but can’t find it. Send me the study and I’ll comment.
The fourth, the Iowa Women's Health Study, analysed the risk of mortality of those taking various supplements versus non-users and found that supplement takers had a reduced risk of death. To quote the study “self-reported use of vitamin B complex; vitamins C, D, and E; and calcium had significantly lower risk of total mortality compared with non-use.” Also, the longer people had taken them the lower was the risk. They also found that supplement users had a lower prevalence of diabetes and high blood pressure, were more likely to exercise and less likely to smoke.
This is one of those chicken or egg situations because there are two different ways of interpreting this: Are supplement takers healthier BECAUSE they take supplements; or do healthier people, CHOOSE to take supplements, the inference being that they were probably healthier to start with and probably don’t need them? Assuming the latter, which is, I think, thew wrong assumption, the researchers then ‘ adjusted’ the results and got to the point where all the positive associations were eliminated, and there was even a hint of a negative for multivitamin use, which is what went out in the press release and hit the headlines.
I think this is more propaganda than science. So that’s the ‘evidence-based science’ to show that supplements are useless or harmful. Four flawed studies. It fails to quote the hundreds, if not thousands of studies that show clear benefit from taking supplements (beyond RDA levels). Let’s look at one, published in 2007 in the Nutrition Journal , which compared three groups: those not supplementing, those taking ‘many’ supplements and those taking the basic ‘RDA’ multivitamins. Those taking ‘many’ supplements had 73% less diabetes risk and 52% less heart disease risk than non-supplement takers and were 74% more likely to rate their own health as good/excellent. Also, 45% of non-supplement takers, 37% of RDA multi takers, and only 11% of ‘many’ supplement takers had elevated homocysteine (above 9). Same pattern for cholesterol. 94% of ‘many’ supplement takers had optimal blood vitamin C levels. None were sub-optimal. 32% of non-supplement takers and 11% of the RDA multi takers were sub-optimal. This is just one study.
If you read my books you’ll find thousands of others showing benefit of ‘optimal’ intakes of nutrients. For those relatively new to all this read the Optimum Nutrition Bible which covers the whole issue of supplementation and what is optimum in detail. To be honest, I’ve never been a fan of basic ‘RDA’ multivitamins based on the so-called Recommended Daily Allowance. I don't think they do much, and that is what some studies show. I call these the Ridiculous Dietary Arbitraries. They bear no resemblance to what you need for optimal health. Take vitamin B12, C and D, for example. Any self-respecting primate will eat at least 1,000mg a day of vitamin C. That’s twenty supermarket oranges. Gorillas in London Zoo are given 2,000mg a day. That’s what I take. The RDA is a measly 80mg. That’s not enough to keep your immune system fighting fit. Also, from November to March there’s no chance of getting enough sunlight to make enough vitamin D. The RDA is 5mcg but we all need at least six times this. Half an hour sun exposure, plus three servings of oily fish and half a dozen eggs might give you 15mcg, so I supplement another 15mcg a day.
The higher your vitamin D levels the longer you live, says a recent study in the European Journal of Clinical Nutrition The older you get, the more vitamin B12 you need to stop both bone and brain shrinkage, according to a study in the journal Neurology in 2008. An estimated two in five people over 61 have insufficient B12 to stop brain shrinkage. By the way, higher dose folic acid also helps prevent memory decline but, as this article rightly points out, there is a risk of high dose folic acid speeding up colo-rectal cancer cell growth. I have written about this in detail and I don’t recommend high dose folic acid unless a) you have had a homocysteine test and your score is high (above 10 mcmol/l) and b) you do not have any ‘pre-cancer’ signs such as gastro-intestinal polyps.
Later in the article the real ignorance of the writer, who is also reporting on a book by Paul Offit which I won't bother to read, implies that Linus Pauling, who put vitamin C on the map, was wrong, died of prostate cancer (at the age of 92) probably because on high dose vitamins and that supplementing 1-2 grams of vitamin C is not ‘natural’. I wrote to the Guardian, who regurgitated this nonsense, saying
“Friday’s article on vitamins showed remarkable bias by completely ignoring either beneficial vitamin studies or recent comprehensive reviews."
For example, the latest 2013 Cochrane review on Vitamin C and colds summarises that
“in adults the duration of colds was reduced by 8% and in children by 14% .The severity of colds was also reduced by regular vitamin C administration.”
The best results have been found in giving high doses in the first 24 hours– a fact that anyone can determine, and many do, for themselves by taking 1 gram an hour on onset of a cold. There is no drug that does this. Stringing together a sentence that Linus Pauling said there is no danger of vitamin C in 1984, then saying he died of prostate cancer in 1994 is a cheap trick. He was 92 at the time. The claim that mega doses ‘can be unsafe’ is simply not backed up by science.
High doses of vitamin C have consistently been shown to lower risk and, in a study last year, to specifically kill prostate cancer cells. The evidence of high dose vitamin C as a potent but non-toxic chemotherapy is becoming increasing well established. (In Japan there are 200 cancer clinics giving intravenous vitamin C as a highly effective cancer therapy.) A daily 1 to 2 grams of vitamin C has been shown to lower cold severity and duration, reduce cancer, diabetes and heart disease risk, as well as lowering blood pressure, cholesterol and blood sugar. Name me a drug that can do all that, and without side-effects.
We should be thanking Pauling, the only man to have ever won two unshared Nobel prizes, and 48 doctorates, instead of falsely trying to discredit him with narrow-minded rhetoric. Yours sincerely, Patrick Holford” Needless to say it never got published. On the question of ‘natural’ what the authors haven’t factored in is that we do not live ‘naturally’. Our biochemical evolution took place during most of humanity’s history in a) a tropical jungle; b) when we spent all day exercising; c) consequently ate much more food and d) only had access to fresh, organic food. A gorilla eats up to 2 grams of vitamin C a day in the jungle, and is given the same as supplements to keep them healthy in zoos. I often think these articles are like intelligence tests.
If a person is sufficiently ignorant, and easily scared off, they will shun supplements. But those with half a brain and a realisation that neither big pharma or big farmer (the food industry) want you thinking you can’t get everything you need from diet. They certainly don’t want you taking supplements for health. It’s drugs all the way. i. WB Grant ‘An estimate of the global reduction in mortality rates through doubling vitamin D levels’ European Journal of Clinical Nutrition (2011), 1–11