Abstract
The triglyceride (TG)-lowering benefits of the very-long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are well documented. Available as prescription formulations and dietary supplements, EPA and DHA are recommended by the American Heart Association for patients with coronary heart disease and hypertriglyceridemia. Dietary supplements are not subject to the same government regulatory standards for safety, efficacy, and purity as prescription drugs are; moreover, supplements may contain variable concentrations of EPA and DHA and possibly other contaminants. Reducing low-density lipoprotein-cholesterol (LDL-C) levels remains the primary treatment goal in the management of dyslipidemia. Dietary supplements and prescription formulations that contain both EPA and DHA may lower TG levels, but they may also increase LDL-C levels.
Two prescription formulations of long-chain omega-3 fatty acids are available in the U.S. Although prescription omega-3 acid ethyl esters (OM-3-A EEs, Lovaza) contain high-purity EPA and DHA, prescription icosapent ethyl (IPE, Vascepa) is a high-purity EPA agent. In clinical trials of statin-treated and non–statin-treated patients with hypertriglyceridemia, both OM-3-A EE and IPE lowered TG levels and other atherogenic markers; however, IPE did not increase LDL-C levels.
Results of recent outcomes trials of long-chain omega-3 fatty acids, fibrates, and niacin have been disappointing, failing to show additional reductions in adverse cardiovascular events when combined with statins. Therefore, the REDUCE–IT study is being conducted to evaluate the effect of the combination of IPE and statins on cardiovascular outcomes in high-risk patients. The results of this trial are eagerly anticipated.
INTRODUCTION
It is now established that omega-3 and omega-6 fatty acids play important roles in human health and disease. Both are considered essential fatty acids, because they are not endogenously synthesized and must be obtained from the diet. Long-chain omega-6 fatty acids include linoleic, gamma-linolenic, and arachidonic acids. Omega 3 Fish Oil 1000mg acids include the long-chain alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
EPA and DHA are often called very-long-chain omega-3 fatty acids. The typical Western diet is rich in omega-6 fatty acids because of the abundance of linoleic acid present in corn, sunflower, and safflower oils.Conversely, omega-3 fatty acids account for only a small percentage of the daily dietary fat intake and are obtained from two main dietary sources—plants and fish. Plant oils from walnuts, flaxseed, and canola contain the omega-3 fatty acid ALA, which is a metabolic precursor of the very-long-chain omega-3 fatty acids EPA and DHA; however, the conversion from ALA to EPA and DHA in the body is inefficient. The most concentrated food source of EPA and DHA is fatty fish such as albacore tuna, salmon, mackerel, sardines, and herring.
Following consumption, polyunsaturated fatty acids, such as the omega-3 and omega-6 fatty acids, are incorporated into cell membranes, where they modulate membrane protein function, cellular signaling, and gene expression. Dietary omega-3 fatty acids compete with omega-6 fatty acids for incorporation into cell membranes. When omega-6 fatty acids predominate in cell membranes, proinflammatory mediators such as thromboxanes, prostaglandins, and leukotrienes are produced via the cyclooxygenase and 5-lipoxygenase pathways. Conversely, the presence of omega-3 fatty acids promotes secretion of anti-inflammatory prostaglandins and less potent leukotrienes, resulting in a shift to a milieu of less inflammatory mediators.These proinflammatory and anti-inflammatory effects represent the primary pharmacological difference between omega-3 and omega-6 fatty acids.
In addition to their anti-inflammatory activity, very-long-chain omega-3 fatty acids have well-described effects on various risk factors for cardiovascular disease. Epidemiological and clinical studies support the cardiovascular benefits of EPA and DHA; however, there is less evidence to support the benefits of ALA. Potential mechanisms for the cardioprotective effects of omega-3 fatty acids include.
The triglyceride (TG)-lowering benefits of the very-long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are well documented. Available as prescription formulations and dietary supplements, EPA and DHA are recommended by the American Heart Association for patients with coronary heart disease and hypertriglyceridemia. Dietary supplements are not subject to the same government regulatory standards for safety, efficacy, and purity as prescription drugs are; moreover, supplements may contain variable concentrations of EPA and DHA and possibly other contaminants. Reducing low-density lipoprotein-cholesterol (LDL-C) levels remains the primary treatment goal in the management of dyslipidemia. Dietary supplements and prescription formulations that contain both EPA and DHA may lower TG levels, but they may also increase LDL-C levels.
Two prescription formulations of long-chain omega-3 fatty acids are available in the U.S. Although prescription omega-3 acid ethyl esters (OM-3-A EEs, Lovaza) contain high-purity EPA and DHA, prescription icosapent ethyl (IPE, Vascepa) is a high-purity EPA agent. In clinical trials of statin-treated and non–statin-treated patients with hypertriglyceridemia, both OM-3-A EE and IPE lowered TG levels and other atherogenic markers; however, IPE did not increase LDL-C levels.
Results of recent outcomes trials of long-chain omega-3 fatty acids, fibrates, and niacin have been disappointing, failing to show additional reductions in adverse cardiovascular events when combined with statins. Therefore, the REDUCE–IT study is being conducted to evaluate the effect of the combination of IPE and statins on cardiovascular outcomes in high-risk patients. The results of this trial are eagerly anticipated.
INTRODUCTION
It is now established that omega-3 and omega-6 fatty acids play important roles in human health and disease. Both are considered essential fatty acids, because they are not endogenously synthesized and must be obtained from the diet. Long-chain omega-6 fatty acids include linoleic, gamma-linolenic, and arachidonic acids. Omega 3 Fish Oil 1000mg acids include the long-chain alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
EPA and DHA are often called very-long-chain omega-3 fatty acids. The typical Western diet is rich in omega-6 fatty acids because of the abundance of linoleic acid present in corn, sunflower, and safflower oils.Conversely, omega-3 fatty acids account for only a small percentage of the daily dietary fat intake and are obtained from two main dietary sources—plants and fish. Plant oils from walnuts, flaxseed, and canola contain the omega-3 fatty acid ALA, which is a metabolic precursor of the very-long-chain omega-3 fatty acids EPA and DHA; however, the conversion from ALA to EPA and DHA in the body is inefficient. The most concentrated food source of EPA and DHA is fatty fish such as albacore tuna, salmon, mackerel, sardines, and herring.
Following consumption, polyunsaturated fatty acids, such as the omega-3 and omega-6 fatty acids, are incorporated into cell membranes, where they modulate membrane protein function, cellular signaling, and gene expression. Dietary omega-3 fatty acids compete with omega-6 fatty acids for incorporation into cell membranes. When omega-6 fatty acids predominate in cell membranes, proinflammatory mediators such as thromboxanes, prostaglandins, and leukotrienes are produced via the cyclooxygenase and 5-lipoxygenase pathways. Conversely, the presence of omega-3 fatty acids promotes secretion of anti-inflammatory prostaglandins and less potent leukotrienes, resulting in a shift to a milieu of less inflammatory mediators.These proinflammatory and anti-inflammatory effects represent the primary pharmacological difference between omega-3 and omega-6 fatty acids.
In addition to their anti-inflammatory activity, very-long-chain omega-3 fatty acids have well-described effects on various risk factors for cardiovascular disease. Epidemiological and clinical studies support the cardiovascular benefits of EPA and DHA; however, there is less evidence to support the benefits of ALA. Potential mechanisms for the cardioprotective effects of omega-3 fatty acids include.
- reduction of triglyceride (TG) levels.
- attenuation of atherosclerotic plaques.
- exertion of antidysrhythmic, antithrombotic, and anti-inflammatory effects.
- lowering of systolic and diastolic blood pressures.
- improvement in endothelial function.
Resource: http://www.ncbi.nlm.nih.gov
Read More: http://www.nutritionforest.com/
Read More: http://www.nutritionforest.com/
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