Effects of similar intakes of marine n-3 fatty acids from enriched food products and fish oil on cardiovascular risk markers in healthy human subjects. Fish and n-3 fatty acids for the prevention of fatal coronary heart disease and sudden cardiac death. Does vegetable oil attenuate the beneficial effects of fish oil in reducing risk factors for cardiovascular disease? Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Fish oil in combination with high or low intakes of linoleic acid lowers plasma triacylglycerols but does not affect other cardiovascular risk markers in healthy men. Influence of alpha-linolenic acid and fish-oil on markers of cardiovascular risk in subjects with an atherogenic lipoprotein phenotype. Docosahexaenoic acid-rich fish oil improves heart rate variability and heart rate responses to exercise in overweight adults. [The effect of omega-3 fatty acids on risk factors for cardiovascular diseases]. Usefulness of omega-3 fatty acids and the prevention of coronary heart disease. Effects of a Small Quantity of ω-3 Fatty Acids on Cardiovascular Risk Factors in NIDDM: A randomized, prospective, double-blind, controlled study Prevention of Fatal Arrhythmias in High-Risk Subjects by Fish Oil n-3 Fatty Acid Intake Dietary fish oil (4 g daily) and cardiovascular risk markers in healthy men. FISH OIL AND VITAMIN E CHANGE LIPID PROFILES AND ANTI-LDL-ANTIBODIES IN TWO DIFFERENT ETHNIC GROUPS OF WOMEN TRANSITIONING THROUGH MENOPAUSE. The Effects of Long-Chain Omega-3 Fish Oils and Multivitamins on Cognitive and Cardiovascular Function: A Randomized, Controlled Clinical Trial Fish-oil concentrate: effects on variables related to cardiovascular disease. A prospective study of plasma fish oil levels and incidence of myocardial infarction in U.S. male physicians. Fish Oil Supplements Lower Serum Lipids and Glucose in Correlation with a Reduction in Plasma Fibroblast Growth Factor 21 and Prostaglandin E2 in Nonalcoholic Fatty Liver Disease Associated with Hyperlipidemia: A Randomized Clinical Trial
There is convincing evidence that consumption of fish and fish oil rich in long-chain ( LC ) n-3 PUFA ( n-3 LCPUFA ) , EPA ( 20 : 5n-3 ) and DHA ( 22 : 6n-3 ) reduce the risk of CHD . The aim of the present study was to investigate whether n-3 LCPUFA-enriched food products provide similar beneficial effects as fish oil with regard to incorporation into plasma lipids and effects on cardiovascular risk markers . A parallel 7-week intervention trial was performed where 159 healthy men and women were r and omised to consume either 34 g fish pâté ( n 44 ) , 500 ml fruit juice ( n 38 ) or three capsules of concentrated fish oil ( n 40 ) , all contributing to a daily intake of approximately 1 g EPA and DHA . A fourth group did not receive any supplementation or food product and served as controls ( n 37 ) . Plasma fatty acid composition , serum lipids , and markers of inflammation and oxidative stress were measured . Compared with the control group , plasma n-3 LCPUFA and EPA : arachidonic acid ratio increased equally in all intervention groups . However , no significant changes in blood lipids and markers of inflammation and oxidative stress were observed . In conclusion , enriched fish pâté and fruit juice represent suitable delivery systems for n-3 LCPUFA . However , although the dose given is known to reduce the risk of CVD , no significant changes were observed on cardiovascular risk markers in this healthy population Large observational studies , r and omized clinical trials , and experimental studies have evaluated the effects of fish and n-3 fatty acid consumption on  fatal coronary heart disease ( CHD ) and sudden cardiac death ( SCD )  , clinical ly defined events that most often share the final common pathway of fatal ventricular arrhythmia . These different study design s , each having complementary strengths and limitations , provide strong concordant evidence that modest consumption of fish or fish oil ( 1 - 2 servings/wk of oily fish , or approximately 250 mg/d of EPA+DHA ) substantially reduces the risk of CHD death and SCD . Pooled analysis of prospect i ve cohort studies and r and omized clinical trials demonstrates the magnitude and dose-response of this effect , with 36 % lower risk of CHD death comparing 0 and 250 mg/d of EPA+DHA consumption ( P < 0.001 ) , but then little additional benefit with higher intakes . Reductions in risk are even larger in observational studies utilizing tissue biomarkers of n-3 fatty acids that more accurately measure dietary consumption . The concordance of findings from different studies also suggests that effects of fish or fish oil on CHD death and SCD do not vary depending on presence or absence of established CHD . The strength and consistency of the evidence , and the magnitude of this effect are each notable . Because more than one-half of all CHD deaths and two-thirds of SCD occur among individuals without recognized heart disease , modest consumption of fish or fish oil , together with smoking cessation and regular moderate physical activity , should be among the first-line treatments for prevention of CHD death and SCD Contradictory reports on the protective effect of fish consumption on cardiovascular disease ( CVD ) risk could be due to variations in the intake of n-3 and n-6 polyunsaturated fatty acids ( PUFAs ) . Metabolic competition between n-3 and n-6 PUFAs suggests that n-6 PUFAs in vegetable oils could attenuate the efficacy of n-3 PUFAs in fish oil to favorably alter endpoints relevant to CVD risk . We determined the effects of varying dietary amounts of fish oil on lipid and thrombotic endpoints relevant to risk factors for CVD and whether these effects were attenuated by vegetable oils . Two r and omized , double-blind , placebo-controlled , parallel studies were conducted in human subjects fed varying amounts of n-3 and n-6 PUFAs ; n-3 PUFA intake was varied by using fish or placebo oil capsules , and n-6 PUFA intake was modified by incorporating varying amounts of safflower oil into the diet . Endpoints included changes in membrane fatty acid composition , blood lipids , and thrombotic profile . The results indicated that absolute amounts of fish oil , and not the relative amounts of fish and vegetable oil ( ratios of n-3 to n-6 PUFAs ) , determined the magnitude of the reduction of arachidonic acid and increase in eicosapentaenoic acid in phospholipids of plasma and platelets . The suppression of plasma triacylglycerols by fish oil was not affected by varying amounts of dietary n-6 PUFAs . Fibrinogen concentrations decreased with 15 g but not with 9 g fish oil/d fed at the same ratio of n-3 to n-6 PUFAs . The efficacy of fish oil in favorably modifying certain risk factors for CVD was not attenuated by vegetable oil Since the first AHA Science Advisory “ Fish Consumption , Fish Oil , Lipids , and Coronary Heart Disease,”1 important new findings , including evidence from r and omized controlled trials ( RCTs ) , have been reported about the beneficial effects of omega-3 ( or n-3 ) fatty acids on cardiovascular disease ( CVD ) in patients with preexisting CVD as well as in healthy individuals.2 New information about how omega-3 fatty acids affect cardiac function ( including antiarrhythmic effects ) , hemodynamics ( cardiac mechanics ) , and arterial endothelial function have helped clarify potential mechanisms of action . The present Statement will address distinctions between plant-derived ( α-linolenic acid , C18:3n-3 ) and marine-derived ( eicosapentaenoic acid , C20:5n-3 [ EPA ] and docosahexaenoic acid , C22:6n-3 [ DHA ] ) omega-3 fatty acids . ( Unless otherwise noted , the term omega-3 fatty acids will refer to the latter . ) Evidence from epidemiological studies and RCTs will be review ed , and recommendations reflecting the current state of knowledge will be made with regard to both fish consumption and omega-3 fatty acid ( plant- and marine-derived ) supplementation . This will be done in the context of recent guidance issued by the US Environmental Protection Agency and the Food and Drug Administration ( FDA ) about the presence of environmental contaminants in certain species of fish . # # # Coronary Heart Disease As review ed by Stone,1 three prospect i ve epidemiological studies within population s reported that men who ate at least some fish weekly had a lower coronary heart disease ( CHD ) mortality rate than that of men who ate none.3–6 ⇓ ⇓ ⇓ More recent evidence that fish consumption favorably affects CHD mortality , especially nonsudden death from myocardial infa rct ion ( MI ) , has been reported in a 30-year follow-up of the Chicago Western Electric Study .7 Men who consumed 35 g or more of fish daily compared with those who consumed none had a relative risk of death from CHD of 0.62 and a relative risk of nonsudden death from MI of 0.33 . In an Both ( n-3 ) long-chain PUFA ( LCPUFA ) and linoleic acid [ LA , 18:2(n-6 ) ] improve cardiovascular disease ( CVD ) risk factors , but a high-LA intake may weaken the effect of ( n-3 ) LCPUFA . In a controlled , double-blind , 2 x 2-factorial 8-wk intervention , we investigated whether fish oil combined with a high- or low-LA intake affects overall CVD risk profile .  Healthy men ( n = 64 ) were r and omized to 5 mL/d fish oil capsules ( FO ) [ mean intake 3.1 g/d ( n-3 ) LCPUFA ] or olive oil capsules ( control ) and to oils and spreads with either a high ( S/B ) or a low ( R/K ) LA content , result ing in a 7.3 g/d higher LA intake in the S/B groups than in the R/K groups . Diet , ( n-3 ) LCPUFA in peripheral blood mononuclear cells , blood pressure ( BP ) , heart rate ( HR ) , and plasma CVD risk markers were measured before and after the intervention . FO lowered fasting plasma triacylglycerol ( TAG ) ( P < 0.001 ) by 51 % and 19 % in the FO+R/K-group and FO+S/B-group , respectively , which was also reflected in postpr and ial TAG measured after the intervention ( P < 0.01 ) . Although a fat x FO interaction was found for monocyte chemoattractant protein-1 , neither the FO nor fat intervention affected fasting plasma cholesterol , glucose , insulin , fibrinogen , C-reactive protein , interleukin-6 , vascular cell adhesion molecule-1 , P-selectin , oxidized LDL , cluster of differentiation antigen 40 lig and ( CD40L ) , adiponectin , or fasting or postpr and ial BP or HR after adjustment for body weight changes . In conclusion , neither fish oil supplementation nor the LA intake had immediate pronounced effects on the overall CVD risk profile  in healthy men , but fish oil lowered plasma TAG in healthy subjects with initially low concentrations We tested the hypothesis that dietary alpha-linolenic acid ( ALA ) can exert effects on markers of cardiovascular risk similar to that produced by its longer chain counterparts in fish-oil . A dietary intervention study was undertaken to examine the effects of an ALA-enriched diet in 57 men expressing an atherogenic lipoprotein phenotype ( ALP ) . Subjects were r and omly assigned to one of three diets enriched either with flaxseed oil ( FXO : high ALA , n = 21 ) , sunflower oil ( SO : high linoleic acid , n = 17 ) , or SO with fish-oil ( SOF n = 19 ) for 12 weeks , result ing in dietary intake ratios of n-6:n-3 PUFA of 0.5 , 27.9 and 5.2 , respectively . The relative abundance of ALA and EPA in erythrocyte membranes increased on the FXO diet ( p < 0.001 ) , whereas both EPA and DHA increased after fish-oil ( p < 0.001 ) . There were significant decreases in total plasma cholesterol within ( FXO -12.3 % , p = 0.001 ; SOF -7.6 % , p = 0.014 ; SO -7.3 % , p = 0.033 ) and between diets ( p = 0.019 ) , and decreases within diets after 12 weeks for HDL cholesterol on flaxseed oil ( FXO -10 % , p=0.009 ) , plasma TG ( -23 % , p < 0.001 ) and small , dense LDL ( -22 % p = 0.003 ) in fish-oil . Membrane DHA levels were inversely associated with the changes in plasma TG ( p= 0.001 ) and small , dense LDL ( p<0.05 ) after fish-oil . In conclusion , fish-oil produced predictable changes in plasma lipids and small , dense LDL ( sdLDL ) that were not reproduced by the ALA-enriched diet . Membrane DHA levels appeared to be an important determinant of these fish-oil-induced effects Dietary fish oil supplementation and regular physical activity can improve outcomes in patients with established CVD . Exercise has been shown to improve heart rate variability ( HRV ) , a predictor of cardiac death , but whether fish oil benefits HRV is controversial . Obese adults at risk of future coronary disease have impaired HRV and may benefit from these interventions . We evaluated the effect of DHA-rich tuna fish oil supplementation with and without regular exercise on HRV in sedentary , overweight adults with risk factors for coronary disease . In a r and omised , double-blind , parallel comparison , sixty-five volunteers consumed 6 g fish oil/d ( DHA 1.56 g/d , EPA 0.36 g/d ) or sunflower-seed oil ( placebo ) for 12 weeks . Half of each oil group also undertook regular moderate physical activity ( 3 d/week for 45 min , at 75 % of age-predicted maximal heart rate ( HR ) ) . Resting HR and the HR response to submaximal exercise were measured at weeks 0 , 6 and 12 . In forty-six subjects , HRV was also assessed by power spectrum analysis of 20 min electrocardiogram recordings taken supine at baseline and 12 weeks . Fish oil supplementation improved HRV by increasing high-frequency power , representing parasympathetic activity , compared with placebo ( P = 0.01 ; oil x time interaction ) . It also reduced HR at rest and during submaximal exercise ( P = 0.008 ; oil x time interaction ) . There were no significant fish oil x exercise interactions . Dietary supplementation with DHA-rich fish oil reduced HR and modulated HRV in keeping with an improved parasympathetic-sympathetic balance in overweight adults with risk factors for future coronary disease UNLABELLED Cardiovascular disease ( CVD ) is associated with dyslipidemia and frequently with insulin resistance , both of which are in general no alleviated by antilipidemic drugs . Our objective was to examine whether a dietary supplement containing omega-3 fatty acids ( n-3 FA ) can reduce the levels of serum lipids , fasting insulin and glucose in documented CVD patients treated by statins or  bezafibrates .  In a double-blind placebo-controlled trial of parallel design , 52 patients , age 69.2 years + /- 3.6 treated by antilipidemic drugs  , were r and omly assigned to receive daily 7 gr of a dietary concentrated supplement containing 67 % n-3 FA ( 185 mg EPA and 465 mg/g DHA ) in a form of spread ( Yamega Ltd , Israel ) or olive oil spread ( placebo ) and recommended to reduce the consumption of omega-6 fatty acids for 12 weeks . The average values + /- SD before and after dietary supplementations were compared . RESULTS 44 patients ( 23 in the n-3 FA group ) completed the study . In the n-3FA group we observed a significant decrease ( p < 0.05 ) of total cholesterol ( 12.2 % ) . LDL-cholesterol ( 16.8 % ) , triglycerides ( 36.1 % ) , insulin in hyperinsulinemic subjects ( > 20 microunits/ml ) ( 34.9 % ) , and no significant changes in HDL-cholesterol and glucose . No hyperglycemia was detected . In the olive oil group we observed a significant decrease ( p < 0.05 ) in the LDL-cholesterol values of 15.5 % and no significant changes in the other parameters . No side effects were reported during the study in any of the participants . Our findings demonstrate that the incorporation of the dietary supplement containing EPA and DHA omega-3 fatty acids reduces significantly the above risk factors for CVD Clinical trial evidence exists that supports a role for the omega-3 polyunsaturated fatty acids in coronary heart disease prevention . However , the results from these clinical trials have varied and were conducted in diverse population groups using several different types of omega-3 polyunsaturated fatty acids , including eicosapentaenoic acid , docosahexaenoic acid , and alpha-linolenic acid ( ALA ) . Thus , we systematic ally review ed previously published reports assessing the different types of omega-3 polyunsaturated fatty acid interventions and cardiovascular outcomes . Fourteen r and omized clinical trials were included in the review . Six trials were included with fish oil , with 1 large trial ( 10,000 patients ) dominating the analysis . In aggregate , the fish oil trials demonstrated a reduction in total mortality and sudden death without a clinical ly significant reduction in nonfatal myocardial infa rct ion . The 6 trials with ALA supplements or an ALA-enriched diet were of poorer design than the fish oil trials and had limited power . Many of the trials with ALA involved other changes in dietary components . In aggregate , the ALA trials demonstrated possible benefits in reducing sudden death and nonfatal myocardial infa rct ion , but with wider confidence intervals than in the fish oil trials . In conclusion , the evidence suggests a role for fish oil ( eicosapentaenoic acid , docosahexaenoic acid ) or fish in secondary prevention because recent clinical trial data have demonstrated a significant reduction in total mortality , coronary heart disease death , and sudden death . The data on ALA have been limited by studies of smaller sample size and limited quality OBJECTIVE To study the effects of a low dose of ω-3 fatty acids on platelet function and other cardiovascular risk factors in patients with non-insulin-dependent diabetes mellus ( NIDDM ) . RESEARCH DESIGN AND METHODS We performed a r and omized , prospect i ve , double-blind , controlled study of a low dose of ω-3 fatty acids ( 2.5 g/day ) in 20 ambulatory subjects with NIDDM . Subjects ingested five 1-g fish oil capsules each containing 0.5 g ω-3 fatty acids or five 1-g safflower oil capsules per day for 6 weeks followed by a 6-week washout period . RESULTS Nine subjects completed the study in each group . Both groups exhibited moderate control of glucose levels ; modest elevations in baseline total cholesterol , low-density lipoprotein ( LDL ) cholesterol , and triglyceride ( TG ) levels ; and normal blood pressure values . In the fish oil group , plasma ω-3 fatty acid levels increased significantly . Fish oil significantly reduced the slope of the dose-response curves for collagen-induced platelet aggregation to one-third the value observed with safflower oil . No difference was observed in collageninduced production of thromboxane A2 ( TXA2 , measured as the stable derivative TXB2 ) , or in adenosine-5'-diphosphate- ( ADP ) induced platelet aggregation or TXA2 generation . Patients with high initial collagen-induced platelet TXA2 production showed a significantly larger drop after fish oil than safflower oil . Fish oil significantly reduced TG levels by 44 mg/dl and decreased upright systolic blood pressure ( sBP ) by 8 mmHg compared with safflower oil . Fish oil caused a significant but small increase in HbA1c ( 0.56 % ) and total cholesterol ( 20 mg/dl ) but had no effect on fasting glucose , high-density lipoprotein cholesterol , or LDL-cholesterol levels . CONCLUSIONS Small doses of fish oil inhibit platelet aggregation and TXA2 production , reduce upright sBP and TG levels , and have only a small effect on glucose and cholesterol levels in patients with moderately controlled NIDDM . Small quantities of ω-3 fatty acids or dietary fish are safe and potentially beneficial in NIDDM patients Background — The long-chain n-3 fatty acids in fish have been demonstrated to have antiarrhythmic properties in experimental models and to prevent sudden cardiac death in a r and omized trial of post – myocardial infa rct ion patients . Therefore , we hypothesized that these n-3 fatty acids might prevent potentially fatal ventricular arrhythmias in high-risk patients . Methods and Results — Four hundred two patients with implanted cardioverter/defibrillators ( ICDs ) were r and omly assigned to double-blind treatment with either a fish oil or an olive oil daily supplement for 12 months . The primary end point , time to first ICD event for ventricular tachycardia or fibrillation ( VT or VF ) confirmed by stored electrograms or death from any cause , was analyzed by intention to treat . Secondary analyses were performed for “ probable ” ventricular arrhythmias , “ on-treatment ” analyses for all subjects who had taken any of their oil supplements , and “ on-treatment ” analyses only of those subjects who were on treatment for at least 11 months . Compliance with double-blind treatment was similar in the 2 groups ; however , the noncompliance rate was high ( 35 % of all enrollees ) . In the primary analysis , assignment to treatment with the fish oil supplement showed a trend toward a prolonged time to the first ICD event ( VT or VF ) or of death from any cause ( risk reduction of 28 % ; P=0.057 ) . When therapies for probable episodes of VT or VF were included , the risk reduction became significant at 31 % ; P=0.033 . For those who stayed on protocol for at least 11 months , the antiarrhythmic benefit of fish oil was improved for those with confirmed events ( risk reduction of 38 % ; P=0.034 ) . Conclusions — Although significance was not achieved for the primary end point , this study provides evidence that for individuals at high risk of fatal ventricular arrhythmias , regular daily ingestion of fish oil fatty acids may significantly reduce potentially fatal ventricular arrhythmias Some epidemiological observations indicate that 1 to 2 weekly servings of fish prevent ischemic heart disease ( IHD ) . This might be explained by an effect of the very-long-chain n-3 polyunsaturated fatty acids ( n-3 VLCPUFA ) of fish oil on lipid metabolism and /or the hemostatic system , both involved in IHD development . We studied the effect of incorporating natural fish oil ( 4 g daily equivalent to 0.91 g n-3 VLCPUFA and corresponding to one to two weekly servings of fatty fish ) into the diet in a 4-week parallel , r and omized , and double-blind trial of 47 healthy males aged 29 to 60 years .  Sunflower oil was used as placebo . The fish oil had no significant effect on plasma lipids , apolipoproteins , lipoprotein(a ) , blood coagulation FVII , fibrinogen , endogenous fibrinolysis , beta-thromboglobulin , von Willebr and factor , glucose , or insulin in fasting blood sample s. In nonfasting sample s ( n = 19 ) , fish oil was associated with an approximately 30 % decline in plasma triglycerides ( P < .02 ) and a 9 % decline in FVII protein ( P < .05 ) , whereas FVII coagulant activity and fibrinolysis were unaffected . In conclusion , our findings indicate that lowering of postpr and ial triglycerides is the only n-3 VLCPUFA effect that could contribute to primary prevention of IHD in healthy middle-aged men as assessed by currently measurable lipid and hemostatic risk markers BACKGROUND studies have investigated the relationship between the transition through menopause and cardiovascular diseases . White population , generally , have lower levels of traditional coronary heart risk factors , particularly dyslipidemia , hypertension , obesity , and diabetes , and lower rates of coronary heart disease mortality , than black population . Furthermore many studies have shown the cardioprotective and anti-inflammatory effects of omega-3 polyunsaturated fatty acids ( eicosapentaenoic acid and docosahexaenoic acid ) of marine origin . The aim of this study was to investigate the effect of omega-3 supplementation , combined or not with vitamin E , on oxidative biomarkers and lipid profiles in nonwhite and white women with dyslipidemia transitioning through menopause . METHODS a r and omized , double-blind , placebo-controlled trial was conducted . Seventy-four eligible women were assigned to receive : fish oil , fish oil plus vitamin E and placebo for three months . At baseline , 45 and 90 days blood sample for biochemical variables and biomarkers of oxidative stress were taken . Socioeconomic and lifestyle variables were collected with st and ardized question naires . RESULTS after 90 days the fish oil plus vitamin E treated group had a significant decrease in total cholesterol and LDL-C. Furthermore , there was a decrease in anti- LDL- autoantibodies after 45 days . Plasma TBARS concentrations were increased after 90 days in the group receiving only fish oil when compared to the placebo and fish oil-vitamin E groups . All of the effects observed were independent of ethnic group . CONCLUSION supplementation with fish oil and vitamin E reduced total cholesterol and LDL-C , but had opposite effects on oxidative stress compared to supplementation with fish oil alone Objective : Fish oils and multivitamins are two of the most commonly used dietary supplements . Fish oil use may reduce vascular risk factors associated with cognitive decline , thus providing benefits to both heart and brain health . Multivitamins may also have direct effects on brain function . The present study investigated the effects of fish oil , with and without the addition of a multivitamin , on cognitive and cardiovascular function . Methods : In a r and omized ,  placebo-controlled  , double-blind fashion , 160 healthy adults aged 50–70 years were r and omized to receive either 3 g of fish oil ( 240 mg eicosapentaenoic acid [ EPA ] + 240 mg docosahexaenoic acid [ DHA ] ) with a multivitamin , 6 g of fish oil ( 480 mg EPA + 480 mg DHA ) with a multivitamin , or 6 g of fish oil without a multivitamin or a placebo . Cognitive performance , brachial blood pressure , and aortic ( central ) blood pressure were measured at baseline , 6 weeks , and 16 weeks . Results : Treatment allocation had no effect on the primary cognitive outcomes at endpoint . Absolute increases in the red blood cell omega-3/6 ratio were associated with improvements in spatial working memory . The group receiving 6 g fish oil without the multivitamin displayed a significant decrease in aortic pulse pressure and aortic augmentation pressure , two measures of aortic blood pressure and aortic stiffness . Conclusions : Fish oil decreased aortic pulse pressure and augmentation pressure . Reductions in aortic blood pressure were not accompanied by consistent improvements in cognition Sixty-four male , healthy volunteers aged 35 - 45 y were r and omly assigned to receive ( as 1-g capsules ) either 14 g fish-oil concentrate/d ( 55 % n-3 fatty acids ) or 14 g olive oil/d for 6 wk . Plasma fibrinogen was reduced by 13 % and serum triglycerides by 22 % after fish-oil supplementation ended . Three weeks after supplementation ended both variables were back to baseline values . An appreciable increase in the ratio of eicosapentaenoic acid to arachidonic acid ( EPA : AA ) in plasma eicosapentaenoic acid to arachidonic acid ( EPA : AA ) in plasma and red blood cell phospholipids occurred during the fish-oil intake . High-density-lipoprotein ( HDL ) cholesterol and HDL2 activity tended to be lowered by fish-oil supplementation . Systolic and diastolic blood pressures , serum cholesterol , gamma-glutamyltransferase , blood glucose , and monocyte low-density-lipoprotein receptor activity did not differ significantly between the two groups . The reduction in plasma fibrinogen concentration seems of special interest because this variable in several recent studies emerges as a separate cardiovascular risk factor with a high predictive value OBJECTIVES This study evaluated whether increased intake of fish oils ( eicosapentaenoic and docosahexaenoic acids ) might reduce the risk of coronary heart disease .  BACKGROUND Observational and clinical studies have suggested that increased intake of fish oils , as reflected in plasma levels of fish oils , may reduce the risk of myocardial infa rct ion . METHODS A nested case-control study was conducted among the 14,916 participants in the Physicians ' Health Study with a sample of plasma before r and omization . Each participant with myocardial infa rct ion occurring during the first 5 years of follow-up was matched by smoking status and age with a r and omly chosen control participant who had not developed coronary heart disease . RESULTS Mean levels of fish oils  ( with 95 % confidence interval [ CI ] for paired differences and p values ) in case and control participants , expressed as percent of total fatty acids , were , for eicosapentaenoic acid , 0.26 versus 0.25 ( 95 % CI -0.03 to 0.05 , p = 0.70 ) in cholesterol esters and 0.56 versus 0.54 ( 95 % CI -0.04 to 0.09 , p = 0.44 ) in phospholipids , and for docosahexaenoic acid , 0.23 versus 0.24 ( 95 % CI -0.07 to 0.04 , p = 0.64 ) in cholesterol esters and 2.22 versus 2.14 ( 95 % CI -0.10 to 0.27 , p = 0.36 ) in phospholipids . Results adjusted for major cardiovascular risk factors showed a very similar lack of association between fish oil levels and the incidence of myocardial infa rct ion . CONCLUSIONS These results indicate no beneficial effect of increased fish oil consumption on the incidence of a first myocardial infa rct ion . However , the effect of very high levels of fish oils could not be evaluated Fish oil has been used effectively in the treatment of cardiovascular disease via triglyceride reduction and inflammation modulation . This study aim ed to assess the effects of fish oil on patients with nonalcoholic fatty liver disease ( NAFLD ) associated with hyperlipidemia . Eighty participants with NAFLD associated with hyperlipidemia were r and omly assigned to consume fish oil ( n=40 , 4 g/d ) or corn oil capsules ( n=40 , 4 g/d ) for 3 months in a double-blind , r and omized clinical trial . Blood levels of lipids , glucose and insulin , liver enzymes , kidney parameters and cytokines at baseline and the end of the study were measured . Seventy people finished the trial .  Plasma concentrations of eicosapentaenoic acid and docosahexaenoic acid significantly increased in the fish oil group after intervention . After adjustment for age , gender and BMI , fish oil significantly decreased fasting serum concentrations of total cholesterol , triglyceride , apolipoprotein B and glucose ( by ( mean±SD ) 0.49±0.43 mmol/L , 0.58±0.89 mmol/L , 0.28±0.33 g/L and 0.76±0.56 mmol/L , respectively , P<0.05 ) , as well as alanine aminotransferase and γ-glutamyl transpeptidase levels ( by ( median ( interquartile ) ) 9.0(0.5 , 21.5 ) and 7.0(2.2 , 20.0 ) IU/L , respectively , P<0.05 ) , significantly increased serum adiponectin levels ( by 1.29±0.62 μg/mL , P<0.001 ) , and reduced serum levels of tumor necrosis factor α , leukotrienes B4 , fibroblast growth factor 21 ( FGF21 ) , cytokeratin 18 fragment M30 and prostagl and in E2 ( by 1.70±1.18 pg/mL , 0.59±0.28 ng/mL , 121±31 pg/mL , 83±60 IU/L and 10.9±2.3 pg/mL , respectively , P<0.001 ) . Corn oil had no effect except for increasing serum creatinine concentrations by 7.7±8.9 μmol/L ( P=0.008 ) . The effects of fish oil on lipids , glucose and γ-glutamyl transpeptidase were positively correlated with the reductions of serum FGF21 and prostagl and in E2 concentrations after adjustment for age , gender and BMI ( r = 0.275 to 0.360 and 0.261 to 0.375 , respectively , P<0.05 ) . In conclusion , our findings suggest that fish oil can benefit metabolic abnormalities associated with NAFLD treatment . Trial Registration
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 .