Omega-3 Fatty Acids and Fish Oil Supplements

These instructions are for patients who are recommended to increase intake of omega-3 fatty acids or take fish oil supplements to reduce risk of heart issues and decrease triglyceride levels.

Important information:

• Omega-3 fatty acids are a source of polyunsaturated fats that are found in plant foods and fish. The main active ingredients in omega-3 fatty acids are EPA (eicosapentanoic acid), DHA (docosahexanoic acid), and ALA (alphalinolenic acid). These can help reduce the risk of heart attacks in high-risk patients and decrease triglyceride levels.

• Supplements can be an easy way to get the required amount of omega-3 fats and may be necessary if a healthcare provider recommends to take large amounts.

Foods high in omega-3 fats

• Foods high in ALA include:

  • Flax and chia seeds

  • Walnuts, tofu, and edamame

  • Flax, walnut, canola, and soybean oils

• Fish high in DHA+EPA include:

  • Herring, salmon, sardines (> 1000 mg per 3 ounce (oz) serving)

  • Canned salmon, trout, oysters, sea bass (500-1000 mg per 3 oz serving)

  • Shrimp, canned light tuna, scallops, tilapia, cod (100-500 mg per 3 oz serving)

• Goal is two 3 oz servings of fish per week for children. Up to 12 oz of fish per week is safe for adults.

• Young children and pregnant women should avoid or limit some fish that may be high in mercury, including:

  • Shark

  • Swordfish

  • Tilefish

  • King mackerel

  • No more than 6 oz white albacore tuna per week

Instructions for taking fish oil supplements:

• Read the label of the fish oil supplement to find the active ingredients of EPA and DHA. Add the amount of EPA and DHA to figure out how many milligrams (mg) are contained in each serving. If using fish oil to lower triglycerides, high doses of EPA+DHA (2000-4000 mg daily) are needed.

• Take fish oil supplements with meals, divide doses over the course of the day, and keep capsules in the refrigerator or freezer to reduce side effects. The most common side effect from supplements is a mild fishy aftertaste.

• Listed below are some popular fish oil supplements and the amount of EPA and DHA per serving.

Reviewed July 2025 by Megan Evans, RD