There was a significant heterogeneity for the impact of CLA  on CRP and IL-6 , but not TNF-α .
Conclusions This meta- analysis showed that CLA supplementation may increase inflammatory markers ( CRP and TNF-α ) .
Background / objectives Conjugated linoleic acid ( CLA ) is a polyunsaturated fatty acid with attractive biological activities .
Numerous studies have been conducted on the inflammation-lowering effects of CLA in in vitro and animal models .
However , the effects of CLA treatment on the inflammatory markers in humans are controversial .
The effects of conjugated linoleic acid supplementation on immune function in healthy volunteers
Objective : To assess the effects of dietary supplementation using two isomeric blends of conjugated linoleic acid ( CLA ) on immune  function in healthy human volunteers . Design : Double-blind , r and omised , placebo-controlled intervention trial . Subjects and intervention : A total of 55 healthy volunteers ( n=20 males , n=35 females ) were r and omised into one of three study groups who received 3 g/day of a fatty acid blend containing a 50:50 cis-9 , trans-11 : trans-10 , cis-12 CLA isomer blend ( 2 g CLA ) , and 80:20 cis-9 , trans-11 : trans-10 , cis-12 ( 80:20 ) CLA isomer blend ( 1.76 g CLA ) or linoleic acid ( control , 2 g linoleic acid ) for 8 weeks . Results : Supplementation with the 80:20 CLA isomer blend significantly ( P≤0.05 ) enhanced PHA-induced lymphocyte proliferation . CLA  decreased basal interleukin (IL)-2 secretion ( P≤0.01 ) and increased PHA-induced IL-2 and tumor necrosis factor α ( TNFα ) production ( P≤0.01 ) . However , these effects were not solely attributable to CLA as similar results were observed with linoleic acid . CLA supplementation had no significant effect on peripheral blood mononuclear cells IL-4 production , or on serum-soluble intercellular adhesion molecule-1 ( sICAM-1 ) or plasma prostagl and in E2 ( PGE2 ) or leukotreine B4 ( LTB4 ) concentrations . Conclusions : This study shows that CLA supplementation had a minimal effect on the markers of human immune function . Furthermore , supplementation with CLA had no immunological benefit compared with linoleic acid . Sponsorship : CLA supplements were provided by Loders Croklaan
There was a significant heterogeneity for the impact of CLA  on CRP and IL-6 , but not TNF-α .
Conclusions This meta- analysis showed that CLA supplementation may increase inflammatory markers ( CRP and TNF-α ) .
Background / objectives Conjugated linoleic acid ( CLA ) is a polyunsaturated fatty acid with attractive biological activities .
Numerous studies have been conducted on the inflammation-lowering effects of CLA in in vitro and animal models .
However , the effects of CLA treatment on the inflammatory markers in humans are controversial .