the university of google strikes again…

In the community paper that arrived in our letterbox this morning there was a letter expressing very strong ‘anti’ feelings with regard to folate. The writer would, he said, boycott bread if this dreadful chemical was added. Google ‘folate & prostate cancer’, he said, & all would be revealed. (This was in reference to the original TV program, where one of the panel of ‘analysts’ commented on a purported link between folate & this particular cancer.)

The writer was probably referring to this item, on ‘Newsmax.com’, which describes a purported link between elevated folate. On the surface the reported data do suggest that  too much folate could be harmful – but towards the end we see the following comment from the scientist who led this particular study: Alternatively, these results may be due to chance, and replication by other studies is needed. Not least because the sample size involved was quite small.

Funnily enough, that same initial google search delivers an earlier, much larger study (Stevens et al. 2006) published in the American Journal of Epidemiology, which notes that folate has important roles in DNA synthesis, repair, and methylation and is inversely associated with the risk of some cancers. Which is reasonable enough, given that the mutations underlying many cancers may involve a failure of DNA repair mechanisms. The research team goes on to say that neither dietary nor total folate intake (ie what someone gains in their diet, plus from supplementation) was associated with prostate cancer overall. However, higher folate levels were associated with a non-significant decreased risk of advanced prostate cancer.

In addition, using Google Scholar will take you to a series of meta-analyses that pool and examine data on the relationship between folate levels and various diseases (including cardiovascular disease and breast cancer) which indicate a causal protective effect of increasing folate intake. And the most recent of these analyses found no evidence supporting the claimed prostate cancer-high folate link.

But I guess the letter-writer didn’t go that far. This does highlight one of the issues with google – that it’s possible to ‘educate’ yourself on an issue without ever going deeply enough, or thinking critically about what’s available. In this particular case, the Newsmax article may have confirmed an existing bias, & that’s been enough for that individual. (And it reinforces my irritation that the TV program that stirred this up didn’t even include a scientist on its ‘panel’… *sigh*)

V.L.Stevens, C.Rodriguez, A.L.Pavluck, M.L.McCullough, M.J.Thun & E.E.Calle (2006) Folate nutrition and prostate cancer incidence in a large cohort of US men. American Journal of Epidemiology 163(11): 989-996. doi:10.1093/aje/kwj126

 

3 thoughts on “the university of google strikes again…”

  • This re-enforces something I pointed out in a conversation elsewhere on the blogosphere that there is a danger in searching for answering using search tools, in that they tend to led you down the path you “want” to go down; you really need to broaden and browse around a topic in order to pick up the other angles and points of view. (In a similar way, I insist on manually scanning about 20-30 journals routinely for new leads as a “browsing” counterpart to balance the keyword-based alerts of new papers I get via PubMed.)
    Here’s one published account that I think is a good take on this saga:
    http://www.odt.co.nz/opinion/opinion/66338/who039s-not-using-their-loaves-debate-over-folate

  • An excerpt from a comment at the article you link to,
    “is it real folic acid or is it a chemical raised to be folic acid”
    a typical example of how the “dreaded chemicals” mentality manifests itself in the wider community.
    Thanks for this, I’ve been in a hole for a couple of weeks and didn’t even know the program was even in danger of being stopped.

  • Alison Campbell says:

    Mmmm. I saw some reported comments from the PM’s science advisor the other day, saying there was a need for more public consultation & that scientists hadn’t done a particularly good job of conveying the underlying science. Well, quite probably that’s true – I hadn’t followed things too closely up until now. But at the same time – where is the opportunity for the scientists to speak in widely accessed public fora? If it’s good enough to seek comment from a health activist, a political science lecturer, a union rep & a broadcaster, why not also include a scientist in the mix? And yes, the Science Media Centre does an excellent job of providing the scientists’ voices – but I don’t see the content relevant to folic acid in bread getting taken up very widely in the mainstream media.
    Sigh… Just as well it’s Friday!

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