title: CLA does not impair endothelial function and decreases body weight as compared with safflower oil in overweight and obese male subjects.
abstract: OBJECTIVE
  Conjugated linoleic acid (CLA) showed a wide range of beneficial biological effects with relevance for cardiovascular health in animal models and humans. Most human studies used olive oil as a reference. This study assessed the effect of CLA as compared with safflower oil on endothelial function and markers of cardiovascular risk in overweight and obese men. Heated safflower oil and olive oil were given for additional descriptive control.
  
  
  METHODS
  Eighty-five overweight men (aged 45-68 years, body mass index 25-35 kg/m(2)) were randomized to receive 4.5 g/d of the CLA isomeric mixture, safflower oil, heated safflower oil, or olive oil in a 4-week double-blind study. Endothelial function was assessed by peripheral arterial tonometry (PAT) index determination in the fasting and postprandial state (i.e., 4 hours after consumption of a fat- and sucrose-rich meal).
  
  
  RESULTS
  CLA as compared with safflower oil consumption did not impair fasting or postprandial PAT index but decreased body weight. CLA as compared with safflower oil did not change total, low-density lipoprotein (LDL), or high-density lipoprotein (HDL) cholesterol; triglycerides; insulin sensitivity indices; C-reactive protein; soluble adhesion molecules; oxidized LDL; lipoprotein a (Lp[a]); paraoxonase; or platelet-activating factor acetylhydrolase (PAF-AH) activity, but significantly reduced arylesterase activity and increased concentrations of the F(2)-isoprostane 8-iso-prostaglandin F (PGF)(2α).
  
  
  CONCLUSIONS
  CLA did not impair endothelial function. Other parameters associated with metabolic syndrome and oxidative stress were not changed or were slightly improved. Results suggest that CLA does not increase cardiovascular risk. Increased F(2)-isoprostane concentrations in this context may not indicate increased oxidative stress.
authors.affiliation: Max Rubner-Institut, Department of Physiology and Biochemistry of Nutrition, Haid-und-Neu-Straße 9, 76131 Karlsruhe, GERMANY. maria.pfeuffer@mri.bund.de
authors.forename: Maria
authors.initials: M
authors.lastname: Pfeuffer
authors.forename: Kerstin
authors.initials: K
authors.lastname: Fielitz
authors.forename: Christiane
authors.initials: C
authors.lastname: Laue
authors.forename: Petra
authors.initials: P
authors.lastname: Winkler
authors.forename: Diana
authors.initials: D
authors.lastname: Rubin
authors.forename: Ulf
authors.initials: U
authors.lastname: Helwig
authors.forename: Katrin
authors.initials: K
authors.lastname: Giller
authors.forename: Julia
authors.initials: J
authors.lastname: Kammann
authors.forename: Edzard
authors.initials: E
authors.lastname: Schwedhelm
authors.forename: Rainer H
authors.initials: RH
authors.lastname: Böger
authors.forename: Achim
authors.initials: A
authors.lastname: Bub
authors.forename: Doris
authors.initials: D
authors.lastname: Bell
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schrezenmeir
mesh_terms: D000368:Aged; D015415:Biomarkers; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000209:etiology; D015237:Dinoprost / Q000378:metabolism; D004311:Double-Blind Method; D004730:Endothelium, Vascular / Q000503:physiopathology*; D028441:F2-Isoprostanes / Q000378:metabolism; D005215:Fasting; D006801:Humans; D044243:Linoleic Acids, Conjugated / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008365:Manometry; D008875:Middle Aged; D009765:Obesity / Q000188:drug therapy* / Q000503:physiopathology; D050177:Overweight / Q000188:drug therapy / Q000503:physiopathology; D008517:Phytotherapy; D019518:Postprandial Period; D012307:Risk Factors; D012450:Safflower Oil / Q000494:pharmacology*; D015431:Weight Loss / Q000187:drug effects*
chemical_list: D015415:Biomarkers; D028441:F2-Isoprostanes; D044243:Linoleic Acids, Conjugated; D012450:Safflower Oil; D015237:Dinoprost; D002265:Carboxylic Ester Hydrolases; C019734:arylesterase