title: Omega-3 fatty acid and ADHD: blood level analysis and meta-analytic extension of supplementation trials.
abstract: Interest in the value of omega-3 (n-3) fatty acid supplementation for treatment of ADHD remains high. No prior meta-analysis has examined whether ADHD is associated with alterations in blood lipid levels and meta-analyses of supplementation have reached conflicting conclusions.
  
  
  METHODS
  We report two new meta-analyses. Study 1 examined blood levels of omega-3 fatty acids in relation to ADHD. Study 2 examined a larger sample of randomized intervention trials than previously reported.
  
  
  RESULTS
  Study 1 included 9 studies (n=586) and found lower overall blood levels of n-3 in individuals with ADHD versus controls (g=0.42, 95% CI=0.26-0.59; p<.001). Study 2 included 16 studies (n=1408) and found that n-3 supplementation improved ADHD composite symptoms; using the best available rating and reporter (g=0.26, 95% CI=0.15-0.37; p<.001). Supplementation showed reliable effects on hyperactivity by parent and teacher report, but reliable effects for inattention only by parent report.
  
  
  CONCLUSIONS
  Omega-3 levels are reduced in children with ADHD. Dietary supplementation appears to create modest improvements in symptoms. There is sufficient evidence to consider omega-3 fatty acids as a possible supplement to established therapies. However it remains unclear whether such intervention should be confined to children with below normal blood levels.
authors.affiliation: Department of Behavioral Neuroscience, School of Medicine, Oregon Health & Science University, Portland, OR, United States.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hawkey
authors.affiliation: Department of Behavioral Neuroscience, School of Medicine, Oregon Health & Science University, Portland, OR, United States; Department of Psychiatry, School of Medicine, Oregon Health & Science University, Portland, OR, United States. Electronic address: niggj@ohsu.edu.
authors.forename: Joel T
authors.initials: JT
authors.lastname: Nigg
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000097:blood* / Q000178:diet therapy*; D002648:Child; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology*; D006801:Humans
chemical_list: D015525:Fatty Acids, Omega-3
keywords: ADHD; Intervention; Meta-analysis; Omega−3; Polyunsaturated fatty acids; Supplementation