Subgroup analysis revealed that increasing dietary ALA tends to elevate CRP concentration  in healthy subjects .
However , the null effect of ALA supplementation on other inflammatory markers was not changed in various subgroups , indicating that the results are stable .
Meta-regression results revealed a negative relationship between the effect size on CRP and its baseline concentration .
No significant publication bias was observed for all inflammatory markers as suggested by funnel plot and Begg ’s test .
Conclusion Our meta- analysis did not find any beneficial effect of ALA supplementation  on reducing inflammatory markers including TNF , IL-6 , CRP , sICAM-1 , and sVCAM-1 .
However , in healthy subjects  , ALA supplementation might increase CRP concentration
Purpose The aim of the current meta- analysis was to investigate the effect of increasing dietary ALA intake on the blood concentration of inflammatory markers including tumor necrosis factor ( TNF ) , interleukin 6 ( IL-6 ) , C-reactive protein ( CRP ) , soluble intercellular adhesion molecule-1 ( sICAM-1 ) , and soluble vascular cell adhesion molecule-1 ( sVCAM-1 )  in adults .
Dietary alpha-linolenic acid inhibits proinflammatory cytokine production by peripheral blood mononuclear cells in hypercholesterolemic subjects.
BACKGROUND Atherosclerosis is a chronic inflammatory disease . We previously reported that a diet high in alpha-linolenic acid ( ALA ) reduces lipid and inflammatory cardiovascular disease risk factors in hypercholesterolemic subjects . OBJECTIVE The objective was to evaluate the effects of a diet high in ALA on serum proinflammatory cytokine concentrations and cytokine production by cultured peripheral blood mononuclear cells ( P BMC s ) from subjects fed the experimental diets . DESIGN A r and omized , controlled , 3-diet , 3-period crossover study design was used . Hypercholesterolemic subjects ( n = 23 ) were assigned to 3 experimental diets : a diet high in ALA ( ALA diet ; 6.5 % of energy ) , a diet high in linoleic acid ( LA diet ; 12.6 % of energy ) , and an average American diet ( AAD ) for 6 wk . Serum interleukin (IL)-6 , IL-1beta , and tumor necrosis factor-alpha ( TNF-alpha ) concentrations and the production of IL-6 , IL-1beta , and TNF-alpha by P BMC s were measured . RESULTS IL-6 , IL-1beta , and TNF-alpha production by P BMC s and serum TNF-alpha concentrations were lower ( P < 0.05 and P < 0.08 , respectively ) with the ALA diet than with the LA diet or AAD .  P BMC production of TNF-alpha was inversely correlated with ALA ( r = -0.402 , P = 0.07 ) and with eicosapentaenoic acid ( r = -0.476 , P = 0.03 ) concentrations in P BMC lipids with the ALA diet . Changes in serum ALA were inversely correlated with changes in TNF-alpha produced by P BMC s ( r = -0.423 , P < 0.05 ) . CONCLUSIONS Increased intakes of dietary ALA elicit antiinflammatory effects by inhibiting IL-6 , IL-1beta , and TNF-alpha production in cultured P BMC s. Changes in P BMC ALA and eicosapentaenoic acid ( derived from dietary ALA ) are associated with beneficial changes in TNF-alpha release . Thus , the cardioprotective effects of ALA are mediated in part by a reduction in the production of inflammatory cytokines
Subgroup analysis revealed that increasing dietary ALA tends to elevate CRP concentration  in healthy subjects .
However , the null effect of ALA supplementation on other inflammatory markers was not changed in various subgroups , indicating that the results are stable .
Meta-regression results revealed a negative relationship between the effect size on CRP and its baseline concentration .
No significant publication bias was observed for all inflammatory markers as suggested by funnel plot and Begg ’s test .
Conclusion Our meta- analysis did not find any beneficial effect of ALA supplementation  on reducing inflammatory markers including TNF , IL-6 , CRP , sICAM-1 , and sVCAM-1 .
However , in healthy subjects  , ALA supplementation might increase CRP concentration
Purpose The aim of the current meta- analysis was to investigate the effect of increasing dietary ALA intake on the blood concentration of inflammatory markers including tumor necrosis factor ( TNF ) , interleukin 6 ( IL-6 ) , C-reactive protein ( CRP ) , soluble intercellular adhesion molecule-1 ( sICAM-1 ) , and soluble vascular cell adhesion molecule-1 ( sVCAM-1 )  in adults .