Combining 21 trials evaluating lipid outcomes , fish oil consumption result ed in a summary net change in triglycerides of -27 ( 95 % CI -33 , -20)mg/dL , in HDL cholesterol of + 1.6 ( 95 % CI + 0.8 , + 2.3)mg/dL , and in LDL cholesterol of + 6 ( 95 % CI + 3 , + 8)mg/dL. There was no effect of fish oil on total cholesterol .
Across studies , higher fish oil dose and higher baseline levels were associated with greater reductions in serum triglycerides .
The evidence supports a dose-dependent beneficial effect of fish oil on serum triglycerides , particularly among people with more elevated levels .
Fish oil consumption also modestly improves HDL cholesterol , increases LDL cholesterol levels , but does not appear to adversely affect glucose homeostasis .
The evidence regarding the effects of omega-3 fatty acids on hs-CRP is inconclusive , as are data on ALA
Greater fish oil consumption has been associated with reduced CVD risk , although the mechanisms are unclear .
Plant- source oil omega-3 fatty acids ( ALA ) have also been studied regarding their cardiovascular effect .
Supplementing lactating women with flaxseed oil does not increase docosahexaenoic acid in their milk.
BACKGROUND Flaxseed oil is a rich source of 18:3n-3 ( alpha-linolenic acid , or ALA ) , which is ultimately converted to 22:6n-3 ( docosahexaenoic acid , or DHA ) , a fatty acid important for the development of the infant brain and retina . OBJECTIVE The objective of this study was to determine the effect of flaxseed oil supplementation on the breast-milk , plasma , and erythrocyte contents of DHA and other n-3 fatty acids in lactating women . DESIGN Seven women took 20 g flaxseed oil  ( 10.7 g ALA ) daily for 4 wk . Breast-milk and blood sample s were collected weekly before , during , and after supplementation and were analyzed for fatty acid composition . RESULTS Breast milk , plasma , and erythrocyte ALA increased significantly over time ( P < 0.001 ) and after 2 and 4 wk of supplementation ( P < 0.05 ) . Over time , 20:5n-3 ( eicosapentaenoic acid , or EPA ) increased significantly in breast milk ( P = 0.004 ) and in plasma ( P < 0.001 ) . In addition , plasma EPA increased significantly ( P < 0.05 ) after 2 and 4 wk of supplementation . There were significant increases over time in breast-milk 22:5n-3 ( docosapentaenoic acid , or DPA ) ( P < 0.02 ) , plasma DPA ( P < 0.001 ) , and erythrocyte DPA ( P < 0.01 ) . No significant changes were observed in breast-milk , plasma , or erythrocyte DHA contents after flaxseed oil supplementation . CONCLUSIONS Dietary flaxseed oil increased the breast-milk , plasma , and erythrocyte contents of the n-3 fatty acids ALA , EPA , and DPA but had no effect on breast-milk , plasma , or erythrocyte DHA contents
Combining 21 trials evaluating lipid outcomes , fish oil consumption result ed in a summary net change in triglycerides of -27 ( 95 % CI -33 , -20)mg/dL , in HDL cholesterol of + 1.6 ( 95 % CI + 0.8 , + 2.3)mg/dL , and in LDL cholesterol of + 6 ( 95 % CI + 3 , + 8)mg/dL. There was no effect of fish oil on total cholesterol .
Across studies , higher fish oil dose and higher baseline levels were associated with greater reductions in serum triglycerides .
The evidence supports a dose-dependent beneficial effect of fish oil on serum triglycerides , particularly among people with more elevated levels .
Fish oil consumption also modestly improves HDL cholesterol , increases LDL cholesterol levels , but does not appear to adversely affect glucose homeostasis .
The evidence regarding the effects of omega-3 fatty acids on hs-CRP is inconclusive , as are data on ALA
Greater fish oil consumption has been associated with reduced CVD risk , although the mechanisms are unclear .
Plant- source oil omega-3 fatty acids ( ALA ) have also been studied regarding their cardiovascular effect .