title: Essential fatty acids in breast milk of atopic mothers: comparison with non-atopic mothers, and effect of borage oil supplementation.
abstract: OBJECTIVE
  To evaluate whether levels of n-6 long chain polyunsaturated fatty acids (LCPs) in human breast milk are related to the mother's atopic constitution, and whether a decreased level can be restored by gamma-linolenic acid supplementation.
  
  
  METHODS
  Cross-sectional study and dietary supplementation trial.
  
  
  METHODS
  20 atopic mothers and 20 non-atopic mothers (controls), all lactating.
  
  
  METHODS
  General population.
  
  
  METHODS
  The atopic mothers were randomly assigned to low (n=10) or high (n=10) dosage oral supplementation with oral borage oil for one week (230 or 460 mg gamma-linolenic acid (18:3n-6) per day).
  
  
  METHODS
  Essential fatty acid composition of the breast milk total fat fraction, determined by gas liquid chromatography.
  
  
  RESULTS
  Arachidonic acid (20:4n-6) was lower in breast milk of atopic mothers compared with non-atopic mothers (0.39 wt% vs 0.46 wt%, difference -0.07% wt% (95% confidence limits -0.13, -0.01 wt%; P<0. 05). The ratio between linoleic acid and the sum of n-6 derivatives did not differ between these groups, indicating no difference in delta-6-desaturase (D6D) activity. Supplementation of the atopic mothers significantly increased the levels of gamma-linolenic acid and dihomo-gamma-linolenic acid in breast milk in a dose-related way, but the level of arachidonic acid was not increased.
  
  
  CONCLUSIONS
  We found a decreased level of arachidonic acid in breast milk in atopic compared to non-atopic mothers, but no indication that the rate-limiting enzymatic step (D6D) is involved. Supplementation increased the precursor pool but did not restore the level of arachidonic acid. We conclude that atopy is related to a metabolic disturbance beyond the D6D enzymatic step. A low level of arachidonic acid in breast milk may be a risk factor for the development of atopy in the infant, especially when the possible underlying metabolic disturbance of EFA metabolism is inherited by the child.
  
  
  BACKGROUND
  F Hoffman-La Roche (Basel, Switzerland) and Friesland Dairy Foods (Leeuwarden, The Netherlands).
authors.affiliation: Department of Epidemiology, Maastricht University, The Netherlands.
authors.forename: C
authors.initials: C
authors.lastname: Thijs
authors.forename: A
authors.initials: A
authors.lastname: Houwelingen
authors.forename: I
authors.initials: I
authors.lastname: Poorterman
authors.forename: A
authors.initials: A
authors.lastname: Mordant
authors.forename: P
authors.initials: P
authors.lastname: van den Brandt
mesh_terms: D000328:Adult; D016718:Arachidonic Acid / Q000032:analysis; D005228:Fatty Acids, Essential / Q000032:analysis*; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000032:analysis; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000378:metabolism*; D008895:Milk, Human / Q000737:chemistry*; D010938:Plant Oils / Q000008:administration & dosage*; D017965:gamma-Linolenic Acid / Q000008:administration & dosage*
chemical_list: D005228:Fatty Acids, Essential; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D010938:Plant Oils; D016718:Arachidonic Acid; D017965:gamma-Linolenic Acid; C079363:borage oil