As the number of cases of both allergies and ADHD disorders are on the rise, it's particularly interesting to examine factors that may be increasing the incidence of both conditions. One somewhat controversial such factor is the consumption of food dyes. The FDA has recently decided that more tests are needed before it can make any recommendations about food dyes, as reported by CNN in FDA advisers want more study of food dye-ADHD link.
As far back as 1975, Dr. Benjamin Feingold put forth in his book Why Your Child is Hyperactive, the idea that food dyes could lead to ADHD. Many in the autism and ADHD community are area of the diet he recommended, the Feingold diet, which essentially eliminates food dyes and additives; many swear by its results. However, ‘reviews of the data found that the correlation between dyes and hyperactivity were inconsistent.’
Many studies on food dye and hyperactivity have been conducted since, but critics are quick to point out apparent weaknesses of the study. For instance, that children's changed behavior was reported by parents rather than clinicians or that dyes were not tested individually.
However, a 2007 study by researchers at the University of Southampton in the United Kingdom showed that artificial food dyes and the preservative sodium benzoate did in fact increase ADHD symptoms in both hyperactive and non-hyperactive children. A 2010 follow-up study examined the connection between food dyes, ADHD, and histamine.
Lead author of the study, Dr. Jim Stevenson testified at the recent FDA hearing about banning or regulating food dye in products: