TY - JOUR
T1 - Meta-analysis of attention-deficit/hyperactivity disorder or attention-deficit/hyperactivity disorder symptoms, restriction diet, and synthetic food color additives
AU - Nigg, Joel T.
AU - Lewis, Kara
AU - Edinger, Tracy
AU - Falk, Michael
N1 - Funding Information:
This study was supported by the North American Branch of the International Life Sciences Institute (ILSI) Technical Committee on Food and Chemical Safety. ILSI North America is a public, nonprofit foundation that provides a forum to advance understanding of scientific issues related to the nutritional quality and safety of the food supply by sponsoring research programs, educational seminars and workshops, and publications. ILSI North America receives support primarily from its industry membership. The Life Sciences Research Organization Inc and Dr. Nigg received a grant from the organization for their work reviewing, analyzing, and summarizing the information contained in this article. Partial funding for this project was also received from the National Confectioners Association .
PY - 2012/1
Y1 - 2012/1
N2 - The role of diet and of food colors in attention-deficit/hyperactivity disorder (ADHD) or its symptoms warrants updated quantitative meta-analysis, in light of recent divergent policy in Europe and the United States. Studies were identified through a literature search using the PubMed, Cochrane Library, and PsycNET databases through February 2011. Twenty-four publications met inclusion criteria for synthetic food colors; 10 additional studies informed analysis of dietary restriction. A random-effects meta-analytic model generated summary effect sizes. Restriction diets reduced ADHD symptoms at an effect of g = 0.29 (95% CI, 0.070.53). For food colors, parent reports yielded an effect size of g = 0.18 (95% CI, 0.080.24; p =.0007), which decreased to 0.12 (95% CI, 0.010.23; p <.05) after adjustment for possible publication bias. The effect was reliable in studies restricted to food color additives (g = 0.21, 95% CI = 0.060.36) but did not survive correction for possible publication bias and was not reliable in studies confined to Food and Drug Administrationapproved food colors. Teacher/observer reports yielded a nonsignificant effect of 0.07 (95% CI = -0.03 to 0.18; p =.14). However, high-quality studies confined to color additives yielded a reliable effect (g = 0.22, 95% CI = 0.100.41, p =.030) that survived correction. In psychometric tests of attention, the summary effect size was 0.27 (95% CI = 0.070.47; p =.007) and survived correction. An estimated 8% of children with ADHD may have symptoms related to synthetic food colors. A restriction diet benefits some children with ADHD. Effects of food colors were notable were but susceptible to publication bias or were derived from small, nongeneralizable samples. Renewed investigation of diet and ADHD is warranted.
AB - The role of diet and of food colors in attention-deficit/hyperactivity disorder (ADHD) or its symptoms warrants updated quantitative meta-analysis, in light of recent divergent policy in Europe and the United States. Studies were identified through a literature search using the PubMed, Cochrane Library, and PsycNET databases through February 2011. Twenty-four publications met inclusion criteria for synthetic food colors; 10 additional studies informed analysis of dietary restriction. A random-effects meta-analytic model generated summary effect sizes. Restriction diets reduced ADHD symptoms at an effect of g = 0.29 (95% CI, 0.070.53). For food colors, parent reports yielded an effect size of g = 0.18 (95% CI, 0.080.24; p =.0007), which decreased to 0.12 (95% CI, 0.010.23; p <.05) after adjustment for possible publication bias. The effect was reliable in studies restricted to food color additives (g = 0.21, 95% CI = 0.060.36) but did not survive correction for possible publication bias and was not reliable in studies confined to Food and Drug Administrationapproved food colors. Teacher/observer reports yielded a nonsignificant effect of 0.07 (95% CI = -0.03 to 0.18; p =.14). However, high-quality studies confined to color additives yielded a reliable effect (g = 0.22, 95% CI = 0.100.41, p =.030) that survived correction. In psychometric tests of attention, the summary effect size was 0.27 (95% CI = 0.070.47; p =.007) and survived correction. An estimated 8% of children with ADHD may have symptoms related to synthetic food colors. A restriction diet benefits some children with ADHD. Effects of food colors were notable were but susceptible to publication bias or were derived from small, nongeneralizable samples. Renewed investigation of diet and ADHD is warranted.
KW - ADHD
KW - meta-analysis
KW - restriction diet
KW - synthetic food color additives
UR - http://www.scopus.com/inward/record.url?scp=83755172575&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=83755172575&partnerID=8YFLogxK
U2 - 10.1016/j.jaac.2011.10.015
DO - 10.1016/j.jaac.2011.10.015
M3 - Article
C2 - 22176942
AN - SCOPUS:83755172575
SN - 0890-8567
VL - 51
SP - 86-97.e8
JO - Journal of the American Academy of Child and Adolescent Psychiatry
JF - Journal of the American Academy of Child and Adolescent Psychiatry
IS - 1
ER -