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 .
The effect of fish oil on blood pressure and high‐density lipoprotein‐cholesterol levels in phase I of the Trials of Hypertension Prevention
Objective To study the effects of moderate doses of fish oil on blood pressure and high-density lipoprotein (HDL)-cholesterol . Methods The participants were 350 normotensive men and women aged 30–54 years who were enrolled from seven academic medical centers in phase I of the Trials of Hypertension Prevention . They were r and omly assigned to receive placebo or 6 g purified fish oil once a day , which supplied 3 g n-3 polyunsaturated fatty acids for 6 months . Results Baseline blood pressure  was ( mean ± SD ) 123±9/81 ±5mmHg . The mean differences in the blood pressure changes between the fish oil and placebo groups were not statistically significant . There was no tendency for fish oil to reduce blood pressure more in subjects with baseline blood pressures in the upper versus the lower quartile ( 132/87 versus 114/75 mmHg ) , low habitual fish consumption ( 0.4 versus 2.9 times a week ) or low baseline plasma levels of n-3 fatty acids . Fish oil increased HDL2-cholesterol significantly compared with the placebo group . Subgroup analysis showed this effect to be significant in the women but not in the men . Increases in serum phospholipid n-3 fatty acids were significantly correlated with increases in HDL2-cholesterol and decreases in systolic blood pressure . Conclusion Moderate amounts of fish oil ( 6g/day ) are unlikely to lower blood pressure in normotensive persons , but may increase HDL2-cholesterol , particularly in women
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 .