Are Multivitamin Users Younger?

June 20, 2009 at 8:30 pm (Nutritionism, Patrick Holford) (Block et al, Bruce Ames, Chen et al, Multivitamins, National Institute of Environmental Health Sciences, nutraingredients.com, Patrick Holford, Telomeres)

Patrick Holford thinks so. Let’s see what evidence he uses as the basis for this assertion.

Well, he is referring to a study authored by H Chen and others that was published online in March 2009 – but the first study he links to is that written by Gladys Block and others in 2007 (http://www.nutritionj.com/content/6/1/30). Eagle-eyed readers with long memories may recall that we’ve (briefly) discussed this paper before. I previously wrote that:

I seem to recall someone on the Radio 4 programme [Rise of the Lifestyle Nutritionists] making the point that the people who were taking supplements may well have been taking other positive steps to improve health/maintain good health. […]

Incidentally, the authors of that study [Block et al] made clear in their conclusion that their “study findings should also be weighed in the context of recent randomized controlled trials and related meta-analyses [39,40] which have raised concern about potential detrimental effects of select dietary supplements, particularly beta carotene and alpha tocopherol.” Ref 39 is to the Bjelakovic study. [http://www.ncbi.nlm.nih.gov/pubmed/17327526 – the study found that “Treatment with beta carotene, vitamin A, and vitamin E may increase mortality. The potential roles of vitamin C and selenium on mortality need further study.”]

The above quote has been edited to add a link to Bjelakovic and a quote from the abstract of this paper – the full text is available via the link. Something I failed to mention in my previous post was something called the bias of compliance. Here’s Gary Taubes writing on the bias of compliance in the New York Times:

Quite simply, people who comply with their doctors’ orders when given a prescription are different and healthier than people who don’t. This difference may be ultimately unquantifiable.

People who take supplements may be different and healthier than people who don’t – yet this difference might not be due to the supplements they take. There is some discussion in the NYT piece of men in a placebo group in a study:

…faithfully taking the placebo cuts the death rate by a factor of two […] people who take their placebo regularly are just different than the others. The rest is a little speculative. Maybe they take better care of themselves in general. But this compliance effect is quite a big effect.

Now that we’ve refreshed our memories with regards Block et al, let’s look at what the authors of the Chen et al study reported in their abstract* and compare it to what Patrick wrote in his blog post. Chen et al: “BACKGROUND: Telomere length may be a marker of biological aging. Multivitamin supplements represent a major source of micronutrients, which may affect telomere length by modulating oxidative stress and chronic inflammation.” Patrick: “A survey of multivitamin users and non-users, measuring their biological age, has found that multivitamin users are younger. […] What is unique about this study is that it measured one of the best indicators of ageing is what’s called telomere length.” [My italics.] Chen et al: “Compared with nonusers, the relative telomere length of leukocyte DNA was on average 5.1% longer among daily multivitamin users (P for trend = 0.002)” Patrick: “telomeres were 5.1% longer in those taking supplements”. And, er, that’s pretty much it. Most of the rest of the post is made up of Patrick discussing the research of Bruce Ames. [EDIT: most of the rest of what I can read, I mean – the rest of the blog post is paywalled. Seriously. Only 100% health members can read further or leave a comment.]

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I note that Holford’s blog post of May 27th ends thus:

Lead researcher Dr Chen, from the National Institute of Environmental Health Sciences, proposes that multivitamins may beneficially affect telomere length via modulation of oxidative stress and chronic inflammation.

This is strikingly similar to reports elsewhere – for example the online supplements and nutrition news service nutraingredients.com** reported, on May 27th, that:

Dr Chen and his co-workers noted that telomere length may therefore be a marker of biological ageing, and that multivitamins may beneficially affect telomere length via modulation of oxidative stress and chronic inflammation.

Unlike Patrick Holford in his blog post, the news service goes on to note, however, that:

Being the first study to report such an association, Dr Chen and his co-workers emphasized that the evidence is only preliminary and that additional epidemiologic studies are required to further explore the association. The implications of the findings in terms of ageing and the etiology of chronic diseases should be carefully evaluated.

PDFs of Holford’s blog post and the Nutraingredients news story: Multivitamin users are younger (PH); Multivitamins linked to younger biological age (NI).

*I would have discussed the full text of this paper had I been able to access it free-of-charge. I am not “one of the most inspiring and informative health and nutritional experts at the cutting edge of health transformation”. If I were, then I would have probably bought access to a journal paper such as this before writing about it. I am, unfortunately, unemployed and I cannot afford to splash out on paywalled articles.

**The nutraingredients.com article uses quotation marks and italics to denote direct quotes from the author, so I had assumed that the sections I quoted from this news service were written by the author of their article Stephen Daniells. It could also be the case that they came from a press release, though. Here is the nutraingredients.com report. [EDIT: I’ve emailed the news service for clarification.]