Saturday 12th April, 2008
If you put aside the fact that most of the people who campaign against food additives should be taken out and shot for crimes against the enlightenment, even a stopped clock shows the right time twice a day, and the evidence overall genuinely shows that some food additives probably aren’t too good for you. Perhaps there should be a special body for issuing warnings on the rare occasions when scares aren’t bogus.
The study that the stories were based on this week was, genuinely, a double blind randomised controlled trial in which a large number of children – around 300 – were given drinks containing colourings and a preservative, or not, and it was done properly. The children were a fairly representative sample of normal kids, people didn’t know which drink they were getting, and the exposure to additives was similar to what you’d get in the real world if you ate bad food, and the kids’ behaviour was measured properly, and there was a small difference between additives and placebo, and it was both statistically significant (which is to say, probably not just a chance finding) and also fairly clinically significant (which is to say, it wasn’t just a genuine but trivial finding).
That’s the research. Entirely separate is what you choose to do about it. Speaking as someone with no interest in making laws, I’ve always been amused by how completely arbitrary the whole process is. For example, the research itself didn’t come out this week, the Food Standards agency knew about the results in March 2007, and the research was fully published in the Lancet last September. The news story is the FSA saying the additives should be phased out, and this is getting more news coverage than the publication of the experimental data itself. We clearly set a lot of store by these decisions.
So how are the judgement calls made? Last September, after they’d already been thinking about it for 6 months, the FSA said something rather different (“avoid additives if your kids is hyperactive”). Now, after a bit more of a think, they call for a ban. Fair enough. A week ago the European Food Safety Authority gave their report, on the exact same evidence, and they say the evidence of harm is poor, and nothing should change.
After six hours of bleary eyed amazement poring through all the relevant documents I can only say that these decisions appear to be entirely random. The EFSA, for example, have produced three PDF reports full of technical material, including a massive statistical e-analysis of the original data (kindly provided by the original researchers) which they harp on about enormously, but which they conclude changes basically nothing. For a massive organisation representing the interests of 700 million people, well-funded by UKIP voters’ tax money, and with a massive advisory panel, they also make some slightly bizarre criticisms of the science.
For example they worry about the GHA, the outcome measure used in the study, because it’s “novel” with “unknown clinical relevance”, although the GHA is simply an aggregate score of a few other outcome measures which are well known and validated. They give dubious weight to a 25 year old meta-analysis with known flaws. It’s all a bit disagreeable, but it’s not quite enough to explain the disparity of view with the FSA. Meanwhile the FSA have produced a lengthy appendix (Annexe II of document FSA- 08/04/04 if you’re interested) detailing the disagreements of interpretation between the UK Committee on Toxicity and the EFSA on 14 technical points, but… there aren’t really any.
I guess hese decisions are a mixture of whim and politics. They’re vaguely informed by research, but only partly, and as it goes, this is entirely as it should be: because it’s a complicated world, and things have risks and benefits beyond the microcosm of a controlled study. You might really like bright green mushy peas, they might sparkle up your day like nothing else. And on the other side of things, additives aren’t just bad in a special, toxicological, narrow sense, but also because they are “facilitators”: they allow us to produce rubbish food, preserve it, and make it more attractive, ultimately producing fat people with quintessentially English teeth. In those terms additives were always part of a bigger problem of cruddy lifestyles, and this goes way beyond 7 special molecules, a few p-values, a headline, an easy scapegoat, and some ratings scales. What a gloriously complicated world.
Seriously, knock yourself out, read all these government reports, it’s good for you.
Here’s the FSA report including Annexe II where they compare the COT and the EFSA takes on the evidence
Here’s the original FSA take
Their stats reanalysis:
The COT analysis Sept 2007
And here’s the report itself: