title: Dietary docosahexaenoic acid as a source of eicosapentaenoic acid in vegetarians and omnivores.
abstract: The utilization of dietary docosahexaenoic acid (DHA; 22:6n-3) as a source of eicosapentaenoic acid (EPA; 20:5n-3) via retroconversion was investigated in both vegetarians and omnivores. For this purpose, an EPA-free preparation of DHA was given as a daily supplement (1.62 g DHA) over a period of 6 wk. The dietary supplement provided for a marked increase in DHA levels in both serum phospholipid (from 2.1 to 7.1 mol% in vegetarians and 2.2 to 7.6 mol% in omnivores) and platelet phospholipid (from 1.1 to 3.4 mol% in vegetarians and 1.4 to 3.9 mol% in omnivores). EPA levels rose to a significant but much lesser extent, while 20:4n-6, 22:5n-6, and 22:5n-3 all decreased. Based on the serum phospholipid data, the retroconversion of DHA to EPA in vivo was estimated to be 9.4% overall with no significant difference between omnivores and vegetarians.
authors.affiliation: Department of Human Biology and Nutritional Sciences, University of Guelph, Ontario, Canada.
authors.forename: J A
authors.initials: JA
authors.lastname: Conquer
authors.forename: B J
authors.initials: BJ
authors.lastname: Holub
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D014676:Diet, Vegetarian; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000378:metabolism*; D005227:Fatty Acids / Q000032:analysis* / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D010743:Phospholipids / Q000097:blood / Q000737:chemistry*
chemical_list: D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D010743:Phospholipids; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid