Food Additives: Are they causing hyperactivity in children?

A recent study suggests there may be a link between common food additives and hyperactive behavior in children. The idea that food additives cause hyperactivity is not new. Dr. Ben F. Feingold first introduced a diet free of food additives as a cure for attention-deficit/hyperactivity disorder (ADHD) in the 1970s. However his method never gained widespread support in the medical community and was heavily criticized by food companies involved in making or distributing food additives. The new research, financed by Britain’s Food Standards Agency and published in The Lancet, is the first double-blind placebo-controlled study of the effect of food additives on behavior.

The three-week study of over 300 children involved two different age groups: 3-year olds and 8 and 9-year olds. Each child spent one week drinking one of three fruit drinks: one containing the amount of additives found in a typical British child’s diet, another without any additives, and the last containing a lower concentration of additives than the first. All three drinks were designed to taste the same. Researchers, ignorant of which children had received which drink, then observed the behavior of the children, paying close attention to the children’s’ attention spans, fidgetiness, restlessness, hyperactivity and other behaviors associated with ADHD. The study found that children were significantly more likely to display these ADHD-like behaviors when drinking the drinks with higher levels of additives. The effect was more pronounced in the 3-year olds than the 8 and 9-year olds. In addition, there were strong individual differences between the children, meaning some did not respond at all to the additives and others responded strongly.

One limitation of the study is that the additive-containing drinks contained a variety of different additives, making it impossible to determine specifically what compound is linked to the behavioral changes. The additive-containing drinks contained a variety of artificial food colorings as well as the compound pictured on the left, sodium benzoate, a common preservative. Sodium benzoate, however, is not only found artificially in foods as a preservative. It is also found naturally in cranberries and prunes.


One obvious question the results of the study bring up is whether these kinds of food additives are causing the high number of ADHD diagnoses in the United States. No other country diagnoses the disorder in children at anywhere near the rate that we do. In addition, the United States consumes 90% of the world’s methylphenidate, a common drug used to treat ADHD, also known by the brand name Ritalin. Some psychologists have questioned whether or not the high rate of diagnoses in the United States has more to do with cultural pressure on children to perform well in school rather than a real mental disorder. The results of the food-additive study, however, suggest that there may be other non-cultural reasons for the high rates of ADHD seen in the United States. Perhaps American children consume more food additives than children in other countries. Given the sheer number of colored and processed foods seen on a regular trip to an American grocery store, this is not hard to imagine. It would be interesting to see a study on the rate of food additive consumption compared to ADHD diagnosis across different countries.

Although it is easy and interesting to speculate on whether additives cause hyperactivity and ADHD in children, it is too early to jump to these kinds of conclusions. As mentioned earlier, there was a high degree of individual difference between children in the study with some children being much more sensitive to the presence of additives than others. It may be the case that the more sensitive children are already more hyperactive or predisposed to ADHD-like symptoms and the additives just exacerbate the problem rather than additives causing ADHD to appear in children who otherwise would be completely normal.

Some scientists in the United Kingdom are already calling for the government to take a more active role in regulating food additives. Although I think the results of this most recent study do call for individuals to be more careful about what foods they and their children consume, at this point I do not think there is enough evidence for governments to make any kind of strict regulations concerning additives. The fact that the study only focused on children leaves open the possibility that additives may not affect adults at all, especially since the younger children were more affected than the older ones. In addition, the high individual differences in sensitivity to the additives calls into question the wisdom of the government regulating foods that may be perfectly harmless even for some children. At this point, I think the only role the government should play is to make sure all additives are listed in food ingredients so that consumers can make informed choices and to fund more research on the subject.