What is Fish Oil?

Fish oil is the oil derived from the tissue of oily fish. Fish oil can be obtained from eating fish or by taking fish oil supplements.

Fish oil contains omega-3 fatty acid, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Omega-3 may also be derived from a plant source containing alpha-linolenic acid (ALA).

This decreases the morbidity and mortality of heart disease by reducing the risk of coronary artery disease, high blood pressure, and fatal heart attacks.

Omega-3 fatty acids are not produced within the body, therefore are obtained from your diet or supplements.

Why do I need it?

Multiple studies have shown that dietary fish or fish oil:

    • Lowers triglycerides
    • Lowers LDL (Lousy Cholesterol) levels
    • Increases HDL (Healthy Cholesterol) levels
    • Lowers blood pressure
    • Reduces the risk of arrhythmias (dangerous abnormal heart rhythms)
    • Reduces the progression of atherosclerosis (plaque build up in arteries)
    • Reduces the risk of heart attacks
    • Reduces inflammation
    • Reduces the risk of stroke
    • Reduces the risk of death

These are all beneficial in reducing the morbidity and mortality of heart disease which is the leading cause of death in the United States.

What are the sources?

Fish oil can be obtained by eating oily fish or fish oil supplements.

Recommended fish include:

    • Anchovies
  • Salmon
    • Bluefish
  • Sardines
    • Carp
  • Striped sea bass
    • Catfish
  • Sturgeon
    • Halibut
  • Trout
    • Herring
  • Tuna
    • Mackerel
  • Whitefish
    • Pompano


Plant derived sources of alpha linolenic acid are also recommended.

Plant sources of ALA include:

    • Canola oil
    • Flaxseed oil
    • Soybeans
    • Tofu
    • Walnuts


The recommended dietary allowance is:How much should I take?

EPA + DHA:  0.3- 0.5 grams

Alpha linolenic acid: 0.8- 1.1 grams

Healthy adults with no cardiovascular disease are recommended to eat fish twice a week.

Please note that fish preparation is to be broiled or baked. Fried fish or fish sandwiches negate the benefits of fish oil and can actually increase the risk of heart disease.

Fish oil capsules are to be taken once daily.

Consult your physician before starting fish oil supplements.

What are the risks?

People with fish allergy should avoid fish oil and omega-3 products derived from fish.

People with allergy to nuts should avoid ALA and omega- 3 products derived from nuts.

Some predatory fish like sharks, cod, and tuna are high in omega- 3 fatty acids, but also have toxic substances. These toxic substances include mercury, dioxin, PCBs, and chlordane which are mostly found in cod liver and shark liver oils. The liver is a major detoxifying and filtering organ, therefore high levels of these toxins are found here. Liver based oils have a higher PCB content than fish oil derived from an entire fish.

Very large amounts of fish oil and omega-3 may increase the risk of hemorrhagic stroke.

Omega- 3 fatty acids may have the potential to slightly increase blood sugar levels. This should be taken with caution in diabetic patients, although no significant long term effects have been noted.

Patients with low blood pressure and those taking blood pressure medications are advised to take fish oils with caution.

Some patients may present with diarrhea at very high doses.

Increased burping, acid reflux, heartburn, abdominal pain, or bloating may occur.

Fishy aftertaste is common.