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 .
Background diet influences the anti-inflammatory effect of alpha-linolenic acid in dyslipidaemic subjects.
Long-chain n-3 PUFA from fish oils are known to have anti-inflammatory effects . We evaluated the effect of alpha-linolenic acid ( ALA ) , precursor of n-3 fatty acids , on serum inflammatory markers and soluble cellular adhesion molecules ( sCAM ) of dyslipidaemic males , relative to their background diet . Participants were assigned to two groups , based upon food intake patterns : ( a ) twenty-one dyslipidaemic subjects who habitually ate a Mediterranean-Cretan-type diet ; ( b ) nineteen dyslipidaemic subjects who normally ate a Westernised Greek diet .  All were supplemented with 8.1 g ALA/d for 12 weeks . We determined serum amyloid A ( SAA ) , C-reactive protein ( CRP ) , macrophage colony-stimulating factor ( MCSF ) , IL-6 , soluble vascular cell adhesion molecule-1 ( sVCAM-1 ) , soluble intercellular adhesion molecule-1 and soluble E-selectin concentrations at the beginning and the end of the ALA supplementation period . Serum baseline concentrations of inflammatory markers and sCAM were similar across the diet groups . Type of diet had a significant impact on the response of inflammatory markers to ALA supplementation . The Westernised Greek diet group showed a reduction in SAA ( P<0.001 ) , CRP ( P=0.002 ) , MCSF ( P=0.005 ) and IL-6 ( P=0.04 ) concentrations . The Mediterranean-Cretan-type background diet group showed a significant reduction only in MCSF concentrations ( P=0.003 ) . The sVCAM-1 concentrations were significantly reduced in both the Westernised Greek diet group ( P=0.001 ) and the Mediterranean-Cretan-type diet group ( P<0.001 ) . The present study demonstrated that ALA supplementation lowered the serum concentrations of inflammatory markers more profoundly when the background diet was rich in saturated fatty acids and poor in MUFA
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 .