Fish Oils, Omega-3s, EPA and DHA: A Review of Benefits

In one of my recent articles, “The Importance of a B-Complex Supplement,” I mentioned heart disease is the leading cause of death in America being responsible for 1 in 4 deaths [1]. I also said B2, or riboflavin, has been shown to lower homocysteine levels, an amino acid linked with heart disease, so if you could decrease it, you could, in turn, reduce the risk of heart disease [2].

In general, medical doctors will not recommend riboflavin based on that study because they either 1) genuinely are not aware of research concerning natural medicine or 2) are incentivized to prescribe pharmaceuticals through kickbacks from pharmaceutical companies. Therefore, it is paramount for you to research, on your own, natural remedies supported by science.

In this article, I am going to dive a little into heart health by examining the benefits of fish oils, omega-3s, EPA and DHA. I will start by explaining how omega-3 fatty acids are good for you, the discuss the overall relationship between a high fish diet and heart disease, and finish be reviewing a handful of studies linking fish, fish oil, and omega-3’s to various areas of heart health.

How Does Omega-3 Promote Heart Health?

Usually, if medical experts recommend eating fish or taking omega-3 supplements for heart health, they do not necessarily know how this diet or these supplements promote heart health. Nonetheless, there is brand-new research which has directly linked omega-3 to heart health because of its protective qualities.

To begin, it is essential to note DNA damage plays a vital role in the creation and development of atherosclerotic cardiovascular disease (CVD). CVD is when the blood vessels that carry oxygen and nutrients from your heart to the rest of your body become thick and stiff and restrict blood flow to tissues and organs. This is commonly known as hardening of the arteries or plaquing.

Studies have shown there is a link between CVD and DNA damage within endothelial cells, the cells which line the interior of blood vessels [4] [5], meaning DNA damage can lead to increased plaquing, which can lead to an increased likelihood of CVD.

This is where omega-3s come into play. A study published in 2017 found EPA and DHA, types of omega-3 fatty acids, attenuate DNA damage in endothelial cells by helping to prevent oxidative stress [3]. Because of the decreased oxidative stress, there is a reduced chance of oxidative stress-induced DNA damage. Thus, resulting in a reduced chance of CVD.

This is one of the first studies which has been able to explain how omega-3s promote heart and vascular health: omega-3s protect DNA.

Relationship Between Diet and Heart Disease

Several studies have investigated the relationship between a high-fish diet and the risk of heart disease, and this section will review two of those studies.

In a 1985 study entitled “The inverse relation between fish consumption and 20-year mortality from coronary heart disease,” researchers investigated the relationship between fish consumption and coronary heart disease in a group of 852 men in the town of Zutphen, located in Gerlderland, Netherlands [6]. The researchers carefully reviewed the diet of men without coronary heart disease (CHD) in 1960. During 20-years of follow up, the researchers observed 78 men who died from CHD, none of which had CHD at the beginning of the study. The researchers found there was an inverse relationship between fish consumption and the chance of mortality of CHD, meaning the more fish in one’s diet, the less chance they were to die from CHD. The researchers concluded, “that the consumption of as little as one or two fish dishes per week may be of preventive value in relation to coronary heart disease” [6].

In 2004, researchers conducted a meta-analysis, a holistic examination of 11 studies and 13 cohorts which included over 220,000 individuals and averaged an 11.8-year follow-up. The study examined the relationship between fish consumption and coronary heart disease. The researchers stated, “Compared with those who never consumed fish or ate fish less than once per month, individuals with a higher intake of fish had lower CHD mortality” [7]. The conclusions aligned with the 1985 study: “These results indicate that fish consumption is inversely associated with fatal CHD. Mortality from CHD may be reduced by eating fish once per week or more” [7].

Though these studies examine fish in diets and not necessary fish oil, one could rationally extrapolate and relate the fish oil in fish to the benefits noted in the reviews.

Fish Oil’s Benefits for Heart Health: Study Review

In this section, we will review studies which have linked fish oil to various areas of heart health. In many of these studies, the term fish oil was used interchangeably with EPA and DHA.

Cholesterol Levels

As noted in a previous article, “Cholesterol: The Basics, Neurological Health, Alzheimer’s,” HDL is not good cholesterol just like LDL is not bad cholesterol; cholesterol is cholesterol, and HDL and LDL are lipoproteins. Since cholesterol cannot dissolve in water, cholesterol needs something to carry it throughout the body: lipoproteins. LDL can be described as the carrier for fresh cholesterol, and HDL can be described as the carrier for recycled cholesterol.

Studies have correlated fish oil to increased levels of HDL – the better, healthier lipoprotein – and play an overall, beneficial role in cholesterol maintenance [8] [9] [10] [11] [12] [13].


A 2009 study showed that taking fish oils produced a significant reduction in triglycerides and the reduction of triglycerides correlated with both EPA and DHA intake and initial levels. The study concluded fish oil supplementation provides a significant dose-dependent decrease of fasting blood triglyceride levels [14].

A 2014 study examined EPA and DHA’s direct effects in lowering triglyceride levels and found the decrease in triglyceride levels was dose-dependently proportional to the intake of EPA and DHA [15].

Blood Pressure

A 2014 study found taking EPA and DHA reduces systolic, the first number in a blood pressure reading and a dose ≥2 grams reduces diastolic blood pressure, the second number in a blood pressure reading [16]. Results were noticed in untreated hypertensive individuals and treated hypertensive individuals, but the effects were more pronounced in untreated individuals [16].

In a 1993 meta-analysis of controlled trials, researchers found similar results [17]. The researchers concluded there was a “dose-response effect” regarding fish oils blood pressure-lowering effect. They found this effect to be notably stronger in individuals who had hypertension, the above-mentioned atherosclerotic disease, and individuals with high cholesterol [17].

In a final, 2016 study, researchers found results which agreed with the above-two studies, but also stated something interesting in their conclusion: “These findings indicate that in adults with isolated systolic hypertension, daily doses of EPA+DHA as low as 0.7 g show clinically meaningful BP reductions, which, at a population level, could be associated with lower cardiovascular disease risk” [18]. The researchers speculated if they were to apply this research to the general population and if the general population were to begin EPA and DHA supplementation, there could be a decreased death risk due to hypertension, which could save lives [18].


Though there is a lot of natural research and information revolving around arrhythmias, which I may investigate in a future article, one study found “regular daily ingestion of fish oil fatty acids may significantly reduce potentially fatal ventricular arrhythmias” [19].

Atherosclerotic Cardiovascular Disease (CVD) or Plaquing

Briefly returning to the relationship as mentioned earlier of omega-3 fatty acids and endothelial disease, studies have shown DHA and EPA supplementation improved the function of cells which link the interior or veins.

A 2012 study concluded, “Supplementation of omega-3 fatty acids significantly improves the endothelial function without affecting endothelium-independent dilation” [20].

A 2003 study investigated why polyunsaturated fatty acids (PUFAs) from oily fish protect against death from cardiovascular disease. Without going super sciency into their research, the researchers found information as to why there are reductions in fatal and non-fatal cardiovascular events, heart attacks, etc., with an increase in PUFA intake [20]. To read the complete study, see reference [21].

A 2013 study produced similar conclusions and stated fatty acids play a positive role in endothelial cell function [22].


My goal in this article was for you to understand the benefits of fish oils, omega-3s, EPA and DHA, have regarding heart and cardiovascular health. New research has allowed us to understand omega-3’s anti-oxidative role in endothelial cells, which explained how omega-3s might be able to help prevent genetic damage. We also reviewed studies investigating the relationship between a high-fish diet and risk of cardiovascular disease, and we finished with a scientific review of various benefits fish oils, omega-3s, EPA and DHA, offer regarding heart and cardiovascular health.

Healthmasters’ Old-Fashioned Cod-Liver Oil and Healthmasters’ Norwegian Omega 3 are excellent sources of fish oils, omega-3s, EPA and DHA.

If you have any questions about these supplements, please feel free to call our office at 800.726.1834.