This morning a friend sent me a link to an article called “Bad Diet the Number One Cause of ADHD”. The author claims food colouring causes ADHD (Attention Deficit Hyperactivity Disorder) in children and that the condition does not exist in countries that do not use the dyes. I don’t know anything about ADHD, food colouring, or children, but I thought I’d write about how to approach something like this sceptically.
First up, look at the source. Be wary if you notice any bias towards a political or religious ideology. This particular article is on a website called Web of Evidence: What They Don’t Want You to Know. It has articles on mind control via the TV, a 9/11 truther who has been locked up for knowing too much and the quote: “propaganda is the executive arm of the invisible government”. The website has an anti-authoritaty political bias.
The article’s author, Betty Hooper, boasts no qualifications in food science or psychiatry, but claims she has spent 25 years collecting “a massive amount” of evidence. She has linked only three citations. One link no longer works. One link is to a reputable study on the effect of food colouring on hyperactivity in children aged three to four. It shows positive results but does not mention ADHD. The third link is to a study called “Treating Food Allergy to Prevent Criminal Behaviour in Community Settings”. It is from the Centre for Complementary Health Studies, University of Exeter. I googled this place and it popped up as an example of the need for regulation in complementary medicine. The study was on “nine children with persistent antisocial, disruptive and/or criminal behaviours”. Yes, a total of nine children were tested. Nine “criminal” children. The study doesn’t mention ADHD.
Another thing to consider is whether the claim goes along with how the world generally works. The claim that removing one thing from our kids’ diets will stop ADHD is similar to that “one weird fruit” that will make you lose weight: it is likely either untrue or simplistic. Probably untrue.
I found some reputable studies that suggested food colouring could be a factor contributing to kids with ADHD. Others showed no significant results. The general consensus is that the more child psychiatry is used in a country, the more documented cases of childhood ADHD there will be. In the words of sceptic Michael Shermer: “It’s good to have an open mind, just not so open that your brain falls out.”