title: Effects of stearidonic acid on serum triacylglycerol concentrations in overweight and obese subjects: a randomized controlled trial.
abstract: OBJECTIVE
  Eicosapentaenoic acid (EPA), which may reduce the risk for coronary heart disease (CHD), can be synthesized at low rates from α-linolenic acid (ALA). The rate-limiting step for this conversion is the Δ6-desaturation of ALA into stearidonic acid (SDA). Thus providing oils rich in SDA may increase endogenous synthesis of EPA, which may subsequently lower serum triacylglycerol concentrations, an effect frequently observed after EPA supplementation. We therefore studied the effects of Echium oil on serum triacylglycerol concentrations and the omega-3 index, which correlate negatively with the risk for CHD.
  
  
  METHODS
  A randomized, double-blind, placebo-controlled crossover trial was conducted, in which 36 healthy overweight and slightly obese subjects daily received 10 g of Echium oil (providing 1.2 g of SDA) or a high oleic acid sunflower oil (HOSO) as control for 6 weeks, with a washout period of at least 14 days. Four subjects dropped out. Differences between periods were tested for statistical significance (P<0.05) using a paired t-test.
  
  
  RESULTS
  Serum triacylglycerol and other lipid concentrations were not significantly affected by consumption of Echium oil compared with HOSO. Echium oil significantly increased percentage of EPA in red blood cell (RBC) membranes with 0.14 ± 0.25% (mean ± s.d.) compared with HOSO (P=0.02). No significant effects on docosahexaenoic acid in RBC membranes or on the omega-3 index were found.
  
  
  CONCLUSIONS
  In healthy overweight and slightly obese subjects, an increased intake of SDA from Echium oil does not lower serum triacylglycerol concentrations. Despite an increase in the percentage of EPA in RBC membranes, the omega-3 index was not changed.
authors.affiliation: Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: D J M
authors.initials: DJ
authors.lastname: Pieters
authors.affiliation: Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: R P
authors.initials: RP
authors.lastname: Mensink
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D018592:Cross-Over Studies; D004281:Docosahexaenoic Acids / Q000097:blood; D004311:Double-Blind Method; D036661:Echium / Q000737:chemistry; D015118:Eicosapentaenoic Acid / Q000097:blood; D004910:Erythrocyte Membrane / Q000737:chemistry; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood*; D019301:Oleic Acid / Q000008:administration & dosage; D050177:Overweight / Q000097:blood*; D010919:Placebos; D010938:Plant Oils / Q000008:administration & dosage; D000074242:Sunflower Oil; D014280:Triglycerides / Q000097:blood*
chemical_list: D015525:Fatty Acids, Omega-3; D010919:Placebos; D010938:Plant Oils; D000074242:Sunflower Oil; D014280:Triglycerides; D004281:Docosahexaenoic Acids; D019301:Oleic Acid; D015118:Eicosapentaenoic Acid; C062895:stearidonic acid