Vitamins – a waste of money or victims of bad science?

Drugs can block vitamin

However that’s not all that’s wrong with this study. It is well known that people who have had a cardiovascular event are almost always put on a cocktail of drugs, what’s less familiar is that drugs often block the effect of vitamins or make you less able to absorb them. This is a factor that is rarely taken into account in vitamin versus placebo or drug trials with sick people.

For example, one analysis of the apparently ineffective trials of B vitamins in secondary prevention of heart disease found that aspirin appears to interfere with the benefits of B vitamins.[3] Those participants on no or low-dose aspirin were more likely to benefit than those taking a high dose. A summary of the trials shows that B vitamins have not proven effective in reducing risk of heart attack, but they have for stroke

Another vitamin/drug interaction involves cholesterol lowering statins which render vitamin E less effective. This is because as well as blocking cholesterol production in the liver, they also cut production of a type of antioxidant called Co-enzyme Q10, which is needed for the vitamin E (also an antioxidant) to ‘refresh’ itself once it’s been ‘reduced’ by disarming a free radical (oxidant). This is very likely why trials adding vitamin E to statin treatment for heart attack patients have found vitamin E adds little or no benefit[4].

Drop the drugs and vitamins work

What’s significant is that although the multivitamin study ignored the confounding variable of multiple drug use, it actually showed this effect at work. A small sub-group of patients refused to take the statins that the rest of the cardiovascular patients were getting, probably because of side effects. These patients did benefit from the vitamins.

Buried in the paper was this contorted sentence: “We found a significant interaction of vitamin therapy with statin use, reflecting a greater effect of high-dose vitamins in patients not receiving a statin.” Unsurprisingly the editorial polemic didn’t point out that there was a statistically significant effect of statins interfering with the benefits vitamin therapy. An honest appraisal of potential benefit of vitamins would have included it because patients would certainly be interested.

The second study gave multivitamins to six thousand doctors aged 65 and older, then followed them up with cognitive assessments done on the telephone over an average of 8.5 years. The vitamin supplement they choose, Centrum Senior, is basically a low dose RDA multivitamin with a little extra B6 (20mg), folic acid (400mcg) and B12 (25mcg).

When the study started, over 12 years ago these might have been reasonable amounts but since then there has been a good randomised controlled trial showing that far higher doses of these three vitamins can prevent or slow down progression of mild cognitive impairment in people ‘at risk’. (See below)

Was the study intended to fail?

Not only does this mean that the study was unlikely to tell you anything useful but the way it was set up suggests it was either intended to fail or that the researchers didn’t understand what they were doing. If you want to see if vitamins can slow cognitive decline the sensible thing to do is to take a group of patients who are showing signs of decline and then see if giving vitamins makes a difference. Then if the vitamins didn’t work you’d expect to see both groups decline at much the same rate; if they did then the vitamin group would have declined more slowly or not at all.

But neither of these things happened. Instead there was very little decline in cognitive ability in either group. At the start of the study both those in the placebo group and those in the B vitamin group scored a healthy 34.3 – no cognitive problems. After 12 years the average in both groups had barely changed – 33.1 in the placebo group and 33.2 in the supplement group– still no problems.

In essence this is a study of a well-educated, reasonably well nourished group of doctors, not ‘at risk’, given relatively low levels of vitamins. Nothing changed. The only real conclusion that can be drawn is that giving a multivitamin based on RDAs does not enhance cognition in people without cognitive impairment. But would you realistically expect it to? To suggest, as the recent editorial did, that this result provides evidence that “B vitamins are harmful or ineffective for chronic disease prevention” is simply ludicrous.

Patrick Holford

Patrick Holford

Patrick Holford is a nutrition expert specialising in mental health. In 1984 he founded the Institute for Optimum Nutrition. He is director of the Food for the Brain Foundation, and it's outpatient clinic, the Brain Bio Centre. He is author of 36 books, including the best-selling Optimum Nutrition Bible and, together with Jerome Burne, Food is Better Medicine than Drugs and 10 Secrets of Healthy Ageing.
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  • Patrick Holford! That’s such a shame. I was starting to like it here.

    • Editorial

      I’d just ask you to read it. Patrick certainly has his detractors but he knows a lot about vitamins and what would be sensible ways to test them and what wouldn’t. Let’s not start off down the ad hominem route. Be really interested to hear your response to what he actually writes.

  • I too have had doubts about some of Mr Holford’s advice in recent years – although I bought a couple of his books before I had stumbled across Gary Taubes’ “The Diet Delusion”.

    However, from what little I know his advice in the present article is spot on. It certainly seems to jibe with Dr Malcolm Kendrick’s views, for which I have the greatest respect.

    • We certainly should try to avoid “ad hominem” arguments. Not only for all the well-known reasons, but also because it seems to me that in the present state of nutrition science it seems unlikely that anyone at all has the whole truth and nothing but the truth. What is important is for us all to work together, as far as possible, and try to fit together the various pieces of the giant nutrition jigsaw.

      • Editorial

        Absolutely and without wanting to go down the conspiracy route it is the case that powerful commercial interests are involved in studies on diet- see Hannah Sutter’s recent article here on SACN. As for supplements pharmaceutical companies readiness to do whatever it takes to protect the bottom line – set out in Melayna Lamb’s post on clinical trials last week – would suggest they probably aren’t reluctant to muddy the water. And that’s quite apart from the fact that evaluating diet and lifestyle interventions is a lot trickier than testing a single drug.

  • Jerome, I can see where Eve and Tom are coming from, Jerome. Patrick can invoke mixed receptions amongst people. But his discussion of homocysteine, B vitamins, heart disease and Alzheimers is highly pertinent because homocysteine is an important link in the chain that joins ’cause and effect’ in these matters. Yes, and I think he is right to intimate we do not get objective and unbiased studies involving vitamin trials and why.

    Homocysteine is an important in the puzzle of chromic disease. In the test kit of diagnostics homocysteine testing can be a reliable indicator of background and lingering oxidative stress. But levels is homocysteine is influenced by several factors. High homocysteine levels can point to nutritional deficiencies and stresses, but there can be alternate nutritional factors at work, and high homocysteine can be induced by factors not directly related to nutrition. As ‘markers’ go homocysteine reliably informs something is wrong, but since several factors can bear upon homocysteine, cortisol being one, and so despite it’s reliability as a risk factor homocysteine lacks specificity in ability to point to underlying cause(s).

    So Patrick is correct to imply supplementation with B vitamins could be prudent, and that the evidential support may be imperfect, but although Patrick’s primary focus is nutrition, compromised nutrition is likely not the only lifestyle or environmental risk factor that has capacity to raise homocysteine levels. Actually the association homocysteine levels may have with cortisol levels links several generally well accepted risk factors with process, but it also points to the involvement of at least two additional potential risk factors that have hitherto been overlooked.

    Part of the difficulty is that informed people, Patrick included, can suggest protocols for treatment ahead of a real understanding of what factors (causes) actually give rise to the need for treatment in the first place. The virtue (or lack of it) in any prospective treatment(s) becomes a lot clearer if the action of the proposed treatment can be cross-referenced against an identified process linking cause with effect.

    In heart disease addressing elevated levels of homocysteine in the most natural ways possible is a way of diminishing atherogenic pressures that lead to atherosclerosis (and arteriosclerosis) and the general package we term’ CVD’ or ‘heart disease’.

    The capacity of cholesterol to potentate the process of atherogenesis still has not been established. In contrast the atherogenic properties, or capacity to potentate atherogenic process, of homocysteine and oxidised cholesterol is supported by evidence. And both homocysteine and insulin are implicated as risk factors for Alzheimers.

    Homocysteine, and oxidised cholesterols, of which ‘cholestane triol’ is one, deserve to get more air time and column inches. Credit to Patrick for his contribution to the process.

  • What irony from a man who has spent years selling the dam things!

  • Aidan Goggins

    I’ve read two rebuttals to these studies.

    The first from Dr Alan Gaby, a US doctor who received his undergraduate degree from Yale University, his M.S. in biochemistry from Emory University, and his M.D. from the University of Maryland. He is past-president of the American Holistic Medical Association and gave expert testimony to the White House Commission on Complementary and Alternative Medicine and has written numerous scientific papers in the field of nutritional medicine. So, quite the authority!

    The second, this article here from Patrick Holford.

    Whilst Patrick’s and my own philosophies are probably best illustrated as a Venn diagram, reading both articles, I can indubitably state that Patrick has presented a far more relevant, thought provoking, and scientifically qualified and rigorous discussion on why we should not discount vitamin use.

    It is a shame if anyone dismisses this piece right off the bat instead of considering the merits of the content presented. I, for one, found many valid and well presented points.

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