Dietary supplementation with cis-9,trans-11 conjugated linoleic acid and aortic stiffness in overweight and obese adults

Am J Clin Nutr. 2010 Jan;91(1):175-83. doi: 10.3945/ajcn.2009.28192. Epub 2009 Nov 18.


Background: Animal studies suggest that dietary cis-9,trans-11 (c9,t11) conjugated linoleic acid (CLA) may inhibit or regress the development of atherosclerosis. The effect of CLA on atherosclerosis has not been assessed in humans.

Objective: We investigated the effect of c9,t11 CLA supplementation on aortic pulse wave velocity (a marker of atherosclerosis) and on cardiovascular risk factors in overweight and obese but otherwise apparently healthy subjects.

Design: In a double-blind, randomized, placebo-controlled, parallel-group trial, we randomly assigned 401 subjects, aged 40-70 y and with a body mass index (in kg/m(2)) > or = 25, to receive either 4 g CLA/d (2.5 g c9,t11 CLA/d and 0.6 g trans-10,cis-12 CLA/d) or placebo supplements for 6 mo. Aortic pulse wave velocity, blood pressure, anthropometric characteristics, and concentrations of fasting lipid, glucose, insulin, and C-reactive protein were measured before and after supplementation.

Results: During the intervention, mean (+/-SE) pulse wave velocity did not change in the c9,t11 CLA group (Delta0.00 +/- 0.07) compared with the placebo group (Delta0.09 +/- 0.06). There was no effect of c9,t11 CLA supplementation on blood pressure, body composition, insulin resistance, or concentrations of lipid, glucose, and C-reactive protein.

Conclusion: This study does not support an antiatherosclerotic effect or an effect on cardiovascular risk factors of c9,t11 CLA. This trial was registered at as NCT00706745.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aorta / drug effects
  • Aorta / physiopathology*
  • Atherosclerosis / prevention & control
  • Blood Pressure / drug effects
  • Body Composition / drug effects
  • Body Mass Index
  • C-Reactive Protein / drug effects
  • C-Reactive Protein / metabolism
  • Cardiovascular Diseases / prevention & control
  • Dietary Supplements*
  • Double-Blind Method
  • Humans
  • Insulin Resistance / physiology
  • Linoleic Acids, Conjugated / administration & dosage
  • Linoleic Acids, Conjugated / pharmacology*
  • Middle Aged
  • Obesity / physiopathology*
  • Overweight / physiopathology*
  • Placebos
  • Pulse
  • Risk Factors
  • Waist-Hip Ratio


  • Linoleic Acids, Conjugated
  • Placebos
  • C-Reactive Protein

Associated data