title: Executive functions and the ω-6-to-ω-3 fatty acid ratio: a cross-sectional study.
abstract: The ω-6 (n-6) to ω-3 (n-3) fatty acid (FA) ratio (n-6:n-3 ratio) was previously shown to be a predictor of executive function performance in children aged 7-9 y.
  
  
  
  We aimed to replicate and extend previous findings by exploring the role of the n-6:n-3 ratio in executive function performance. We hypothesized that there would be an interaction between n-3 and the n-6:n-3 ratio, with children with low n-3 performing best with a low ratio, and those with high n-3 performing best with a high ratio.
  
  
  
  Children were recruited on the basis of their consumption of n-6 and n-3 FAs. The executive function performance of 78 children aged 7-12 y was tested with the use of the Cambridge Neuropsychological Test Automated Battery and a planning task. Participants provided blood for plasma FA quantification, and the caregiver completed demographic and activity questionnaires. We investigated the role of the n-6:n-3 ratio in the entire sample and separately in children aged 7-9 y (n = 41) and 10-12 y (n = 37).
  
  
  
  Dietary and plasma n-6:n-3 ratio and n-3 predicted performance on working memory and planning tasks in children 7-12 y old. The interaction between dietary n-6:n-3 ratio and n-3 predicted the number of moves required to solve the most difficult planning problems in children aged 7-9 y and those aged 10-12 y, similar to results from the previous study. There was also an interaction between the plasma n-6:n-3 ratio and n-3 predicting time spent thinking through the difficult 5-move planning problems. The n-6:n-3 ratio and n-3 predicted executive function performance differently in children aged 7-9 y and in those aged 10-12 y, indicating different optimal FA balances across development.
  
  
  
  The n-6:n-3 ratio is an important consideration in the role of FAs in cognitive function, and the optimal balance of n-6 and n-3 FAs depends on the cognitive function and developmental period studied. This trial was registered at clinicaltrials.gov as NCT02199808.
authors.affiliation: Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC.|Center for Biobehavioral Health, The Research Institute at Nationwide Children's Hospital, Columbus, OH; and.
authors.forename: Kelly W
authors.initials: KW
authors.lastname: Sheppard
authors.affiliation: Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC; carol_cheatham@unc.edu.|Nutrition Research Institute, University of North Carolina at Chapel Hill, Kannapolis, NC.
authors.forename: Carol L
authors.identifier: 0000-0002-8841-0105
authors.initials: CL
authors.lastname: Cheatham
mesh_terms: D000367:Age Factors; D002648:Child; D002657:Child Development; D003071:Cognition / Q000187:drug effects*; D003430:Cross-Sectional Studies; D004032:Diet; D056344:Executive Function / Q000187:drug effects*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D009483:Neuropsychological Tests; D013850:Thinking / Q000187:drug effects
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6
keywords: CANTAB; Electric Maze Task; executive functions; fatty acids; middle childhood