New study confirms link between attention deficit hyperactive disorder and artificial food colours, but the UK Food Standards Agency is downplaying the evidence and offering misleading advice, coinciding with an aggressive campaign of disinformation from industry. Prof. Peter Saunders
Read the list of ingredients on the label of a tin or packet of food carefully and you will often find several identified only by a number;these are additives for flavouring, colouring and preserving.
As the additives are seldom found in food prepared at home, many people are concerned about how safe they are, especially when consumed by children and over a period of many years. While the additives have been tested, this may have been some time ago. Furthermore, each of additives would have been tested separately, whereas a typical food product will contain several in combination, and most people consume more than one such product in the course of a day.
One area of concern is attention-deficit/hyperactivity disorder (ADHD) in children. The prevalence of ADHD has greatly increased over the past fifty years, and it has been widely suspected that some artificial food colourings (AFCs) are contributing to that.
As long ago as 1975, physician BenFeingold pointed out that the increase in what he called H-LD (hyperkinesis and learning disabilities) was correlated with the growth in consumption of soft drinks and synthetic flavours since World War II [1]. Drawing also on his clinical experience, he wrote: “I believe that it is more than suggestive that a relationship exists between H-LD and the artificial colors and flavors in our food.” There have been a number of studies since, and while the results have not been conclusive, they have certainly not been reassuring.
In 2004, two researchers at Columbia University carried out a meta-analysis of this work, i.e.. they used statistical techniques to combine results from different experiments. They found that even allowing for publication bias and other limitations, there was evidence that some AFCs contribute to hyperactivity [2].
Shortly after this result appeared, the UK Food Standards Agency (FSA) commissioned a team at Southampton University to conduct a further investigation. This was a follow up to an earlier study of children on the Isle of Wight carried out in 1999-2000, which had reported a connection between AFCs and ADHD, but had not led to action because the results were again considered inconclusive [3].
The Southampton group carried out a randomised, double-blind, placebo-controlled crossover trial in which they gave children two different mixes of additives in amounts that corresponded to what they would get if they ate about five ounces of sweets a day. The mixes each consisted of a commonly used preservative, sodium benzoate (E211) and four colourings: Mix A, Sunset yellow (E110), Tartrazine (E102), Carmoisine (E122), Ponceau 4R (E124) (This is the same mixture that was used in the Isle of Wight study); Mix B, Sunset yellow (E110), Quinoline yellow (E104), Carmoisine (E122), Allura red (E129)
The children enrolled in the study were 153 3-year-olds and 144 8/9-year- olds; they were observed and rated by teachers and parents and the older children were also given a computerised test of attention.
In May 2007, reports began to appear in the media that the Southampton study had found a link between food colouring and ADHD and had submitted their report to the FSA. The FSA’s Committee on Toxicity (COT) had met in closed session on March 20 (its meetings are usually open), and decided not to reveal the contents until they had been peer reviewed and published in a scientific journal.
It is hard to find a justification for the FSA’s decision. Despite what has been written recently by people who ought to know better, peer review is not the sine qua non of science. Basically, it involves two or three unpaid referees reading a manuscript and deciding whether on the face of it (and it has to be on the face of it, because they see neither the experiments nor the researchers’ notebooks) the paper is worth publishing, possibly with alterations. It is a useful part of the process of research, but it is inherently limited in what it can achieve.
In any case, not all science is peer reviewed. In particular, many of the results submitted by commercial companies to regulatory authorities like the FSA to be used in decisions about health and safety are never refereed. They are never published in journals, so the scientific community at large is not given the opportunity to judge the quality of the work. On the contrary, much of what is submitted to regulatory authorities is hidden from public review and even the authorities themselves on grounds of “commercial confidentiality”.
What could a journal’s referees do that the members of the COT could not have done themselves? Or, if none of the COT had the necessary expertise – in which case we might ask whether the right people have been chosen as members – they could simply have asked a couple of experts to review the paper for them, and that could have been done in a day or two. With results that could have such major implications for public health, it was wrong to delay for the six months or more it typically takes before an article appears in a journal.
In the event, the paper did pass peer review and was finally published in the Lancet in September 2007. The researchers did find a link between artificial food additives and hyperactivity in children [4]. Mix A, but not Mix B had a significantly adverse effect compared with placebo for all 3-year-olds; for the 8/9-year-olds, both Mix A and Mix B had a significant adverse effect compared to placebo. The researchers conclusion was unequivocal (see Box 1).
Box 1
What the scientists say:
“The present findings, in combination with the replicated evidence for the AFCA effects on the behaviour of 3-year-old children, lend strong support for the case that food additives exacerbate hyperactive behaviours (inattention, impulsivity, and overactivity) in children at least up to middle childhood. Increased hyperactivity is associated with the development of educational difficulties, especially in relation to reading, and therefore these adverse effects could affect the child’s ability to benefit from the experience of schooling. These findings show that adverse effects are not just seen in children with extreme hyperactivity (ie, ADHD), but can also be seen in the general population and across the range of severities of hyperactivity(emphasis added). ….
“We have found an adverse effect of food additives on the hyperactive behaviour of 3-year-old and 8/9-year-old children. Although the use of artificial colouring in food manufacture might seem superfluous, the same cannot be said for sodium benzoate, which has an important preservative function. The implications of these results for the regulation of food additive use could be substantial.”
The conclusion is clear and unusually strong for a scientific paper, and you might have thought the FSA would have taken some appropriate action: to ban the additives, or at least start phasing them out, or even just to insist on some warning labels similar to those on foods that might contain nuts.
Instead, at this point, Dr Clare Baynton of the FSA said that the additives were safe and approved for use in food. “It is for a parent to know what foods their children are susceptible to and whether their children react to to specific types of food” [5].
The FSA did announce that it was revising its advice to consumers. This advice, however, is not to be found in the shops or on the products themselves. But if you go to the FSA website and click on “Colours and hyperactivity” and then on “Agency revises advice on certain artificial colours” – which you aren’t very likely to do unless you know what you are looking for – you find the most feeble and misleading advice [6] (see Box 2), which is considerably at odds with the strong conclusion of the scientific report [4] (compare with Box 1).
Box 2
What the FSA advises:
“After considering the COT’s opinion on the research findings we have revised our advice to consumers: if a child shows signs of hyperactivity or Attention Deficit Hyperactivity Disorder (ADHD) then eliminating the colours used in the Southampton study from their diet might have some beneficial effects.
“However, we need to remember that there are many factors associated with hyperactive behaviour in children. These are thought to include genetic factors, being born prematurely, or environment and upbringing.
“The Agency has shared these research findings with the European Food Safety Authority (EFSA), which is currently conducting a review of the safety of all food colours that are approved for use in the European Union, at the request of the European Commission. This review is being undertaken because of the amount of time that has elapsed since these colours were first evaluated.
“If parents are concerned about any additives they should remember that, by law, food additives must be listed on the label so they can make the choice to avoid the product if they want to.”
Once again, the FSA is guilty of ignoring and downplaying scientific evidence of serious food hazards, and to the most vulnerable in our population. (We have recently documented this in the case of GM food and feed [8] (GM Food Nightmare Unfolding in the Regulatory Sham, I-SIS scientific publication).
The Southampton study specifically drew attention to adverse effects not just in children with ADHD, but also in the general population. Vague reference to premature birth, environment or upbringing that might be associated with hyperactivity is simply irrelevant and misleading in this context. The FSA is leaving it to parents – those who manage to find the advice in the first place - if they are concerned, and the clear implication is that most of them shouldn’t be. The FSA’s press release, contains the phrase, “ if real” in referring to the “observed increases in hyperactive behaviour”.
It is up to the parents to look for the E numbers. Or presumably, as children often buy their own sweets, it’s up to parents to teach their 8 year-olds to look for the E numbers. If the products are sold unpackaged, they are expected to check with the vendor or the manufacturer, and what they should do about food served in restaurants or school dinners is not explained.
Industry meanwhile, has begun its aggressive campaign of disinformation. Speaking for the Food and Drink Federation, Julian Hunt said [5], “It is important to reassure consumers that the Southampton study does not suggest there is a safety issue with the use of these additives.” This is surely a misrepresentation of what the Lancet paper said, but not many consumers are going to read the paper.
The FSA is clearly not doing its job of protecting consumers. It appears more concerned to protect the interests of the food industry in unnecessarily delaying decisions, and then in failing to act and downplaying and misrepresenting the evidence when it goes against the industry.
Despite what the FSA and the Food and Drink Federation would have us believe, the Southampton study [4] confirms the evidence that some food additives can have an adverse effect on children’s behaviour. In some this may be serious enough to be classified as ADHD; in others it may be milder and perhaps not be recognised as a specific condition at all, but still enough to detract from their experience in school and, presumably, in other ways as well. We should also ask what other effects these additives may be having, and whether they really affect only children.
The sensible way forward is surely the one suggested by the Southampton group at the end of their paper. A substance such as sodium benzoate may or may not be hazardous, and we must do our best to find out. But at least it serves a useful function, and in the end we may well decide that, even applying the precautionary principle, the possible risk is outweighed by the advantages in using it. But where additives serve no useful function, or one that could be served by other substances that we know more about, then they should be banned or phased out. There is no reason to risk our health and that of our children merely to have foodsthat come in colours that make them easier to sell.
Article first published 01/10/07
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