Like many other people with young children, I watched chef Jamie Oliver’s new television series about school dinners with the kind of horrified fascination that train wrecks can engender.
The shocking state of canteen food highlighted by the programme has rightly prompted national debate in the UK. Children simply cannot grow up healthy if they’re allowed to eat a daily supply of chips, frozen pizza and grotesque meat-based products - a fact that’s all the more pertinent in this age of obesity.
But part of the reason that Oliver’s campaign has prompted such a reaction is, I think, down to another diet-related issue: fascination with the link between nutrition and behaviour in children, which has reached a fever pitch among many parents.
In one episode of the programme, the parents of tearaway kids were instructed by Oliver to cut out junk foods, fizzy drinks and sweets and replace them with healthier alternatives. Interviewed a couple of weeks later, they said they had noticed an amazing difference in behaviour - one that reversed itself almost instantly when they caved in and allowed the children a “treat” meal of processed food and soft drink.
But from a scientific perspective there’s a world of difference between anecdote and solid evidence. Parents who actively decide to alter their children’s diet are more likely to see a behaviour change, because that’s what they want to see. Having said that, the evidence supporting a link between nutrition and the mind is already more than suggestive and growing stronger.
Take artificial colourings and other “E” numbers denoting additives, for example, which have been in the bad books for years now. Last year came the publication of the best evidence to date supporting the idea that cutting additives out of a child’s diet can lead to significant improvements. In a study sponsored by the UK government, Professor John Warner and colleagues studied 277 three-year-olds on the Isle of Wight, and categorised them into four groups - those with an allergy, those with signs of attention deficit hyperactivity disorder (ADHD), children with both and those with neither.
The children were put on a diet that eliminated artificial food colourings and benzoate preservatives. The researchers then supplemented the diet with a fruit drink that either did or did not contain the artificial junk. The children’s behaviour was assessed by parents, who did not know which drink the child was drinking.
The study found significant reductions in hyperactive behaviour when the children were not getting the additives, and increases in hyperactivity when they were. “It wasn’t just a sub-group of children who were affected, it was all the children, it was across the board,” says Dr Alex Richardson, of Oxford University, a researcher in the field and director of the charity Food and Behaviour Research.
Richardson herself is the senior researcher in a study looking at the latest hot-button subject in diet and behaviour, fish oils - which many parents will tell you can transform the behaviour of a “problem” child.
Fish oils are high in Omega-3 fatty acids, which are known to be important for brain development, hormonal balance and the immune system, but which many modern diets lack. There are even suggestions that the evolution of humans’ cognitive function is linked to eating fish.
Evidence of the benefits of fish oil supplements is not conclusive. But it’s about to get a boost, as a study conducted by Richardson and colleagues in children with dyspraxia, a condition characterised by problems with physical co-ordination, has now been accepted for publication in a scientific journal.
The study has received premature media coverage, perhaps unsurprisingly. “We get a huge amount of interest,” Richardson told me last week. “It’s mostly the parents and also teachers who are interested in whether diet affects behaviour.”
The study looked at children classified as suffering from dyspraxia, but many were also dyslexic and ADHD. Because the results are yet to be published, Richardson wouldn’t divulge the full outcome. But she would say that giving children a daily fish oil supplement containing half a gram of Omega-3 fatty acids resulted in significant improvements. “We’ve shown you can improve behaviour and learning with these oils.”
It’s not the first study to show dramatic improvements in behaviour with nutritional supplements. As long ago as 2002, researchers studying teens in a young offenders institution found that dietary changes could reduce violence. They looked at the effects of supplemental fatty acids, minerals and vitamins on the behaviour of 231 prisoners. They found striking results: incidents of antisocial behaviour fell by 35 per cent among inmates who took the supplements for two weeks or more compared with those who didn’t.
This evidence is compelling - so why hasn’t more been done by government, schools or, for that matter, parents?
It’s a mystery, says Richardson: “Everyone’s aware that a lousy diet is bad for your physical health but it has taken a lot longer for people to twig that the brain is also part of your body and is possibly the first place you would be likely to see an effect.” For our children’s sake, we should pay more attention to the evidence.
