title: Obesity and weight loss alter serum polyunsaturated lipids in humans.
abstract: Serum omega 6 (n-6) fatty acids were assessed in 12 obese women during an outpatient very-low-calorie diet (VLCD). Ten subjects (S10) achieved a mean weight loss of 17 kg over 3-5 mo (initial weight-for-height 157%). Serum was obtained before (baseline) and monthly during the VLCD and from five of them (S5) after 2-3 mo of weight stability (refed) at 21 kg of loss. At baseline for S10, the serum phospholipid (PL) 20:4 omega 6 was 9.16 wt% and differed from normal (12.81 wt%) by P less than 0.0001, but cholesterol ester (CE) 20:4 omega 6 did not differ from normal. During 3 mo of VLCD, the S10 serum PL and CE 18:2 omega 6 fell (P less than 0.005 and 0.0001, respectively). Serum PL 20:4 omega 6 rose to normal during VLCD months 1-3 (P less than 0.01) while the serum CE 20:4 omega 6 rose above normal (P less than 0.0002). During the VLCD, S5 results paralleled S10. However when refed, S5 PL and CE 18:2 omega 6 and 20:4 omega 6 all reverted to baseline (PL 20:4 omega 6 below normal, P less than 0.001). Serum PL 20:4 omega 6 is low in moderate obesity, corrects to normal during a VLCD, but regresses to the predict abnormality after weight loss.
authors.affiliation: Department of Food Science and Nutrition, University of Minnesota, St Paul.
authors.forename: S D
authors.initials: SD
authors.lastname: Phinney
authors.forename: P G
authors.initials: PG
authors.lastname: Davis
authors.forename: S B
authors.initials: SB
authors.lastname: Johnson
authors.forename: R T
authors.initials: RT
authors.lastname: Holman
mesh_terms: D000328:Adult; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000097:blood; D002788:Cholesterol Esters / Q000097:blood; D004038:Diet, Reducing; D005231:Fatty Acids, Unsaturated / Q000097:blood*; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood*; D009765:Obesity / Q000097:blood* / Q000178:diet therapy; D010743:Phospholipids / Q000097:blood; D015431:Weight Loss
chemical_list: D001095:Arachidonic Acids; D002788:Cholesterol Esters; D005231:Fatty Acids, Unsaturated; D008055:Lipids; D010743:Phospholipids; D016718:Arachidonic Acid