British researchers have found evidence that suggests artificial food
colors and additives may exacerbate hyperactivity in children, according to a
study published online in The Lancet on September 6.
Donna McCann, Ph.D., and others from the University of Southampton in
England, tested the effects of commonly used food coloring agents and the
preservative sodium benzoate on hyperactivity levels in two groups of
children: one group consisted of 153 3-year-olds and the other of 144 8- and
9-year-olds. During the six-week study with a within-subject cross-over
design, the children consumed a set amount of drink mix every day. The drink
mixes used in the study were three mixed fruit juices (two active mixes and
one placebo) that looked and tasted the same; the only difference was that the
two active drinks contained a mixture of artificial food colors and sodium
benzoate (see FIG2 for
ingredients in the active mixes).
Each week, one of the three drink mixes (active mix A, active mix B, or
placebo) was delivered to the children's homes for their consumption during
that week. On weeks 2, 4, and 6, mix A, mix B, and placebo were delivered in a
random sequence. The actual drink delivered to each home at any given week was
blinded to the child, the parents, the teachers, and the researchers. Weeks 1,
3, and 5 were washout periods when the children received the placebo
drink.
The children's behavior was measured throughout the study period using a
global hyperactivity aggregate (GHA) score. The scores were compiled based on
observation and ratings by parents and teachers. The children, parents,
teachers, and researchers were unaware of the actual drink (active or placebo)
given to the children at any given time. The study was commissioned by the
U.K. Food Standards Agency (FSA), which regulates food safety.
The children had statistically significant increases in GHA scores
associated with the active drink mixes in most but not all analyses. Among the
73 3-year-olds who did drink more than 85 percent of the assigned mixes in all
six weeks and had all the GHA scores, and after controlling for several
potentially confounding factors, mix A had a significant effect on GHA scores
compared with placebo. Mix B, however, did not have a significant effect
compared with placebo. Among the 91 8- and 9-year-olds who drank more than 85
percent of the assigned drinks, both mix A and mix B had a significant effect
on their GHA scores compared with placebo.
"This is a very important study, rigorously designed by outstanding
investigators, and represents an important cautionary note on the need for
more studies of the impact of various food additives on children's
behavior," psychiatrist Peter Jensen, M.D., the director of the REACH
(Resource for Advancing Children's Health) Institute, commented to
Psychiatric News. "While it could not be determined from this
study alone that such additives have a causative role in ADHD, the findings do
suggest that additional, similarly carefully designed studies are needed in
children generally and in children at risk for ADHD specifically."
Previous studies had implicated artificial food colors and additives in
increased hyperactivity in children with ADHD. In contrast, this study
recruited a representative sample of children in the community with and
without ADHD and showed increased hyperactivity within the overall study
population.
Because of the composition of the active drink mixes, the authors
acknowledged that it was not possible to parse out an individual additive's
effect on hyperactivity. They pointed out that sodium benzoate has an
important preservative function, and the implication of these findings could
be substantial for the food industry.
If these findings are replicated by other investigators and in other
populations, said Jensen, regulatory agencies should scrutinize the risks of
the widespread use on such additives in foods. Based on this study, the FSA
recently updated its advice to consumers, BBC News reported.
"If [children show] signs of ADHD, then eliminating the colors used
in the Southamptom study from their diet might have some beneficial
effects," said Andrew Wadge, director of food safety policy and chief
scientist at the FSA.
Both Wadge and Jim Stevenson, Ph.D., senior author of the study and a
professor at Southampton University, both acknowledged that many other factors
contribute to ADHD and simply eliminating artificial food colors and sodium
benzoate will not necessarily prevent hyperactivitiy disorders.
An abstract of "Food Additives and Hyperactive Behaviour in
3-Year-Old and 8/9-Year-Old Children in the Community: A Randomised,
Double-Blinded, Placebo-Controlled Trial" is posted at<www.thelancet.com/journals/lancet/article/PIIS0140673607613063/abstract>.▪