Should we worry about additives?

The Friday Lecture: Dr CLIVE HUNT, senior lecturer in nutrition in the department of applied sciences at the University of Huddersfield, looks at the controversial issue of food additives.

OVER the years food additives have been the subject of much hype in relation to how necessary and safe they are.

However, the fact is that they are here to stay. They are needed to ensure stability of food supply and make a major contribution to both safety (via a whole array of preservatives) and attractiveness of food (via enhancement of sensory properties such as colour and odour).

Additives that are allowed have been subjected to rigorous safety checking by the UK government, co-ordinated by the Food Standards Agency (FSA) and also, these days, by the European Food Safety Authority (EFSA).

Nevertheless, these bodies periodically review safety matters in the light of any new evidence from scientific studies. One such study, which is still having an impact, was a medical study conducted at Southampton University and reported a couple of years ago.

Certain food additives may make some children “hyperactive” (which some experts think affects 2 to 5 per cent of children in the UK). Hyperactivity describes a range of behaviours where children are erratic, excitable and find it hard to concentrate.

This study involved 153 three-year old and 144 eight and nine-year-old children and was well-designed scientifically.

Teachers and parents rated children for signs of hyperactivity using pre-validated scoring scales. The children were given either a drink containing an additive cocktail or a placebo drink. The placebo tasted and looked the same as the cocktail but had no additives.

All children were given each type of drink in different phases of the trial. The trial lasted several weeks. It was designed to mimic the sort of intake that children might have from a range of popular foods and drinks.

The additive cocktail contained sodium benzoate (E211 — a preservative used in many soft drinks and sauces) and various artificial colours, including sunset yellow (E110), quinoline yellow (E104), carmoisine (E122), allura red (E129), tartrazine (E102) and ponceau 4R (E124).

These colours are used in a wide range of soft drinks, sweets, cakes, biscuits and also in some savoury products such as the bread-crumbs coating some brands of fish fingers.

The results showed that, on average, there was a small but statistically significant increase in hyperactive behaviour with the additives. There was a lot of individual variation and not all children were affected.

So should we be alarmed?

Many scientists feel that we should not panic about this but keep it under review. A child can be hyperactive because of genetics, environment or upbringing. It might have nothing to do with their diet.

In any case, one study on its own, however well designed, cannot give absolute proof of an effect.

However, the evidence is building up and the issue should not be ignored. The FSA has revised its advice to parents, saying that “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.”

But the FSA is against a total ban of these additives and wants to wait for the outcome of an ongoing review by EFSA of all food colours currently approved in the EU.

Nevertheless, they are encouraging a voluntary ban of these six colours and currently are building a list (available on the FSA website) of food manufacturers, retailers and caterers who have discontinued their use. So, for example, Asda, Co-op, Sainsbury, M & S and Tesco no longer use the colours in their own-label products.

Meanwhile, parents would be prudent to discourage children from consuming large amounts of luridly-coloured soft drinks and confectionery.

The food additives might increase hyperactivity in some children although they will probably have little or no effect on most.

The brightly-coloured varieties are often the cheaper varieties.

This type of food and drink will usually be low in nutritional value and high in sugar, anyway.

Peaks and troughs in blood-sugar levels in themselves, regardless of food additives, could affect a child’s behaviour!