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Nothing Fishy about Fish Oil and Omega-3 Fatty Acids Category: Heart Disease by - February 23, 2014 | Views: 16955 | Likes: 3 | Comment: 3  

With hundreds of supplements and herbals available, it is difficult to determine which are worth taking. Fish oil and omega-3 fatty acid products are two very commonly asked about supplements that may be beneficial to some people.

Fish oils and omega-3 fatty acid daily servings

What Are Omega-3 Fatty Acids

Having a balanced diet includes eating certain types of fat that allow our bodies to make cells, communicate between cells, and store energy. Omega-3 and omega-6 fatty acids are two particularly important types of (polyunsaturated) fat that help regulate the cells in the body to perform at optimal levels. These fatty acids are not produced in the body and must be obtained by eating certain foods.

Omega-3 fatty acids (FA) are primarily found in fish oil, and certain plant and nut oils. Omega-6 FA are primarily found in palm, soybean, rapeseed, and sunflower oils. Ideally, balanced diets contain 1 part omega-3 for every 4 parts omega-6. However, most American diets contain 5 to 7 times less omega-3 than they should. This would suggest a need for either increasing omega-3 FA or decreasing omega-6 FA intake.

Sources of Omega-3 Fatty Acids

There are multiple types of omega-3 fatty acids that are important for body cell health, including:

  • docosahexanenoic acid (DHA)
  • eicosapentaenoic acid (EPA)
  • docosapentaenoic acid (DPA).

DHA and EPA, found in oily fish and fish oil supplements, are particularly important in heart and brain cell structure. Fish high in these omega-3 FA include:

  • Anchovies
  • Herring
  • Salmon
  • Bluefish
  • Lake trout
  • Striped Sea Bass
  • Carp
  • Mackerel
  • Tuna (albacore)
  • Catfish
  • Pompano
  • Whitefish
  • Halibut
Alpha-linoleic acids (found in tofu/soybeans, walnuts, flaxseed oil, and canola oil) are converted in the body into DHA and EPA, serving as sources of omega-3 fatty acids. Omega-3 fatty acids are also found in certain plant and nut oils.

What are the Benefits of Omega-3 Fatty Acids

In addition to supporting a balanced diet, there may be long term health benefits associated with increased omega-3 FA levels in the body. The most significant evidence of the benefits is prevention of coronary heart disease (CHD), high triglycerides, high blood pressure, rheumatoid arthritis, and prevention of further heart problems in people with heart disease. These benefits may be related to increased flexibility of cells in the body as well as changes in DNA activation when omega-3 FA are present.

Omega-3 fatty acids regulate the heart and provide protection against irregular heartbeats that may lead to death. Thus, the primary benefits of daily fish oil (1 g/day) intake are related to reducing sudden cardiac death events and CHD-related death (including heart attack) in populations with and without CHD. In patients with previous heart attacks, the reduction in sudden cardiac death is seen as early as 3 months of treatment.

At higher doses (>2 g/day), omega-3 fatty acids also significantly reduce triglyceride levels. Higher doses have greater effects, and four grams daily may lower triglyceride levels by up to 40%, which is similar to other prescription drugs used for treating high cholesterol or triglycerides (for example, statins). This supports the use of Lovaza, a prescription fish oil supplement, to manage high triglyceride levels.

How Much Omega-3 Fatty Acid Is Needed

In healthy individuals, the World Health Organization and governmental health agencies recommend consuming 0.3 to 0.5 grams EPA + DHA daily and 0.8 to 1.1 grams of daily α-linolenic acid to decrease risk of sudden cardiac death and coronary heart disease-related death.

This EPA + DHA dose may be obtained by:

  • eating fatty fish (3.5 ounces) 3 to 4 times per week
  • daily fish oil supplements which generally contain between 200 and 800 mg of EPA + DHA per 1 gram fish oil

Eating fatty fish is preferred to fish oil supplements due to the additional beneficial proteins, vitamins, and selenium. However, this must be balanced with increased mercury and PCB (polychlorinated biphenyls) levels found in some fish (swordfish, king mackerel, tilefish, and albacore tuna). Fish oil supplements do not carry the same risk of these toxicities.

In patients with existing cardiovascular diseases, daily doses of EPA + DHA may need to be slightly higher (1 to 1.5 g EPA + DHA).

Significant decreases in triglyceride levels are seen when used at doses greater than 2 grams of EPA + DHA daily. Improvements may take months to years of treatment. Specific dosing recommendations should be made in collaboration with a medical practitioner.

What are the Safety Concerns of Omega-3 Fatty Acids

  • Omega-3 is likely safe when included in the diet (1-2 fish meals per week).
  • Omega-3 is likely safe when taken as a supplement in recommended doses (up to 3 grams) for up to 3.5 years.
  • At doses up to 4 g /day, increased bleeding has not been observed. High doses of fish oil (3 to 15 g /day) increased bleeding time, but this has not been associated with higher rates of bleeding.
  • Use caution in people being treated for high blood pressure, bleeding disorders, blood sugar disorders, hormonal imbalances, abnormal heart rhythms, asthma, inflammatory bowel disease, liver disease, or those taking herbs and supplements.
  • Omega-3 should be only be used under medical care in people with heart disease.
  • Possible side effects include acid reflux, bad breath, bad taste in the mouth, bloating, burping, diarrhea, dizziness, excess fat in the stool, vitamin E deficiency, vomiting, and weight gain.

Omega-3 Supplement Products

Over the Counter Products: There are hundreds of over the counter omega-3, polyunsaturated fat, fish oil supplements available to consumers as pills, liquid concentrates, or enriched margarines. When deciding which product to choose, evaluate products based on the amount of EPA and DHA contained in each serving.

A common amount of omega-3 fatty acids in fish oil capsules is 0.18 grams (180 mg) of EPA and 0.12 grams (120 mg) of DHA. If the capsule contains 200 to 800 mg of EPA + DHA, then is sufficient for protection of heart health.

Supplement products are not FDA regulated as other medicinal products, so it is important that you are choosing a product in which the contents have been validated. Look for products that have seals of approval, such as USP Verified, ConsumerLab, or GMP (Good Manufacturing Practice).

Prescription Products: Lovaza is a prescription strength fish oil supplement that is FDA-approved for reducing high triglycerides. Each 1 gram liquid gel capsule contains 375 mg DHA, 465 mg EPA, and soybean oil. 

Diet: Fish contain different amounts of omega-3 fatty acids. Generally, 3.5 ounces (or ¾ cup) of a fatty fish at least twice a week help satisfy omega-3 FA requirements (See picture).


Omega-3 fatty acid is believed to benefit health by lowering triglycerides and reducing the risk of heart attack, abnormal heartbeat, and stroke. It has also been studied for other benefits, but with less supporting data. Increasing dietary fish to at least twice weekly or daily supplements of fish oils with omega-3 fatty acids can help provide protection for heart health in both healthy individuals as well as those with previous heart conditions. Higher doses may be necessary for other benefits of lowering blood pressure and triglyceride levels, as well as for rheumatoid arthritis symptoms.

Dietary fatty fish is preferred to daily supplements, however, fish choices should avoid those high in mercury levels. Fish oil supplements do not carry the risk of mercury toxicity.

Also Read: Health Benefits of Omega-3 Fatty Acids (Fish Oil) Supplementation

For additional information about fish oil and heart health, visit


Natural Standard Monograph: Omega-3 fatty acids, fish oil, alpha-linolenic acid. Natural Standard: The Authority on Integrative Medicine; 2013. Accessed February 5, 2014.

Mozaffarian D. Fish oil and marine omega-3 fatty acids. In: UpToDate, Fletcher RH (Ed), UpToDate, Waltham, MA. Accessed on February 5, 2014.

Oken E. Risks and benefits of fish consumption and fish oil supplements during pregnancy. In: UpToDate, Ramin SM (Ed), UpToDate, Waltham, MA. Accessed on February 5, 2014.

Kris-Etherton PM, Harris WS, Appel LJ. AHA Scientific Statement: Fish Consumption, Fish Oil, Omega-3 Fatty Acids, and Cardiovascular Disease. Circulation. 2002; 106:2747. Accessed February 5, 2014.

Simopoulos AP. The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomed Pharmacother. 2002 Oct;56(8):365-79.

News Ask the Expert: Fish Oil Dosing. Natural Standard: The Authority on Integrative Medicine; March 2006. Accessed February 5, 2014.


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