title: Dietary omega-6 fatty acid lowering increases bioavailability of omega-3 polyunsaturated fatty acids in human plasma lipid pools.
abstract: BACKGROUND
  Dietary linoleic acid (LA, 18:2n-6) lowering in rats reduces n-6 polyunsaturated fatty acid (PUFA) plasma concentrations and increases n-3 PUFA (eicosapentaenoic (EPA) and docosahexaenoic acid (DHA)) concentrations.
  
  
  OBJECTIVE
  To evaluate the extent to which 12 weeks of dietary n-6 PUFA lowering, with or without increased dietary n-3 PUFAs, alters unesterified and esterified plasma n-6 and n-3 PUFA concentrations in subjects with chronic headache.
  
  
  METHODS
  Secondary analysis of a randomized trial. Subjects with chronic headache were randomized for 12 weeks to (1) average n-3, low n-6 (L6) diet; or (2) high n-3, low n-6 LA (H3-L6) diet. Esterified and unesterified plasma fatty acids were quantified at baseline (0 weeks) and after 12 weeks on a diet.
  
  
  RESULTS
  Compared to baseline, the L6 diet reduced esterified plasma LA and increased esterified n-3 PUFA concentrations (nmol/ml), but did not significantly change plasma arachidonic acid (AA, 20:4n-6) concentration. In addition, unesterified EPA concentration was increased significantly among unesterified fatty acids. The H3-L6 diet decreased esterified LA and AA concentrations, and produced more marked increases in esterified and unesterified n-3 PUFA concentrations.
  
  
  CONCLUSIONS
  Dietary n-6 PUFA lowering for 12 weeks significantly reduces LA and increases n-3 PUFA concentrations in plasma, without altering plasma AA concentration. A concurrent increase in dietary n-3 PUFAs for 12 weeks further increases n-3 PUFA plasma concentrations and reduces AA.
authors.affiliation: Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA. Electronic address: ameer.taha@nih.gov.
authors.forename: Ameer Y
authors.initials: AY
authors.lastname: Taha
authors.affiliation: Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Yewon
authors.initials: Y
authors.lastname: Cheon
authors.affiliation: Department of Physical Medicine and Rehabilitation, Program on Integrative Medicine, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Keturah F
authors.initials: KF
authors.lastname: Faurot
authors.affiliation: Nutrition Research and Metabolism Core, North Carolina Translational Clinical Sciences Institute, University of North Carolina, Chapel Hill, USA.
authors.forename: Beth
authors.initials: B
authors.lastname: Macintosh
authors.affiliation: Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Sharon F
authors.initials: SF
authors.lastname: Majchrzak-Hong
authors.affiliation: Department of Neurology, Program on Integrative Medicine, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Mann
authors.affiliation: Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Hibbeln
authors.affiliation: Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Amit
authors.initials: A
authors.lastname: Ringel
authors.affiliation: Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA; Department of Physical Medicine and Rehabilitation, Program on Integrative Medicine, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Ramsden
mesh_terms: D000328:Adult; D000818:Animals; D059350:Chronic Pain / Q000097:blood / Q000178:diet therapy; D019587:Dietary Supplements; D005227:Fatty Acids / Q000097:blood*; D015525:Fatty Acids, Omega-3 / Q000097:blood*; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage / Q000493:pharmacokinetics; D005260:Female; D006261:Headache / Q000097:blood / Q000178:diet therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D051381:Rats; D013997:Time Factors
chemical_list: D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6
keywords: Arachidonic acid (AA); Chronic headache; Fish; Linoleic acid (LA) lowering; Omega-3 and omega-6 polyunsaturated fatty acids (PUFAs); Plasma fatty acid concentrations