II. Indications

  1. Coronary Heart Disease Prevention (1 gram/day)
    1. Degree of cardiovascular benefit is unclear (see efficacy below)
    2. Still recommended for Coronary Artery Disease secondary prevention
    3. Siscovick (2017) Circulation 135:e867-84 +PMID: 28289069 [PubMed]
  2. Other indications under study (2-4 grams/day)
    1. Hypertriglyceridemia
    2. Hypertension
    3. Rheumatoid Arthritis

III. Physiology

  1. Essential Fatty Acids
  2. Properties
    1. Anti-inflammatory
    2. Antithrombotic
    3. Antiarrhythmic
    4. Vasodilatory
  3. Benefits
    1. Significant effects at 1 gram/day of omega-3
      1. Reduces risk of sudden death
      2. Reduces all-cause mortality
    2. Other effects at 2-4 grams/day of omega-3
      1. Precaution: These doses require further study
      2. Lowers serum Triglycerides
        1. High doses of omega-3 may raise LDL Cholesterol
      3. Reduces symptoms in Rheumatoid Arthritis
      4. Lowers Blood Pressure in Hypertension

IV. Types: Polyunsaturated Fatty Acids (PUFA)

  1. Acids from fish and fish oils
    1. Eicosapentaenoic Acid (EPA)
      1. Does not raise LDL Cholesterol significantly
      2. Triglycerides lowered more effectively when EPA used in combination with DHA
    2. Docosahexaenoic Acid (DHA)
      1. Increases LDL Cholesterol
      2. Significantly boosts Triglyceride lowering effect of EPA
  2. Acids from seed, green leafy vegetables, nuts and beans
    1. Alpha linolenic Acid (ALA)

V. Sources: Plant (mostly Alpha linolenic Acid, about a third the potency of EPA/DHA)

  1. Nuts
    1. Almonds
    2. Dried butternut
    3. English walnuts
  2. Miscellaneous
    1. Flaxseed
    2. Raw Soybeans
    3. Pinto beans
    4. Wheat germ
    5. Purslane
    6. Leeks
  3. Oils
    1. Canola oil
    2. Fish oil
    3. Flaxseed oil
    4. Walnut oil
    5. Soybean oil
      1. Also contains Omega-6 Fatty Acids (prothrombotic)

VI. Sources: Fish (EPA or DHA per 3 ounces of fish)

  1. General
    1. Omega 3 Fatty Acid content varies considerably
      1. Depends on species, season, diet, and processing
  2. Fish with high omega 3 levels (>1 grams/3 ounces)
    1. Albacore tuna
      1. Fresh: Up to 1.3 grams
      2. Canned white in water: Up to 0.75 grams
    2. Herring, sardines or anchovy: Up to 1.7 grams
    3. Halibut: Up to 1 gram
    4. Mackerel: Up to 1.5 grams
    5. Salmon
      1. Atlantic, Chinook: Up to 1.5 grams
      2. Sockeye: Up to 0.7 grams
  3. Fish and seafood with lower omega 3 levels (<0.4 grams)
    1. Catfish
    2. Alaskan king crab
    3. Flounder or sole
    4. Haddock
    5. Shrimp

VII. Sources: Supplement

IX. Efficacy: Variable evidence in Cardiovascular Risk Reduction

  1. Study of 11,000 post-Myocardial Infarction patients on 850 mg Omega-3 Fatty Acids per day
    1. Had a 45% reduction in cardiac death and 20% mortality reduction overall
    2. Burr (1989) Lancet 2:757-61 [PubMed]
  2. Italian Study of 12,000 patients with multiple Cardiovascular Risk Factors
    1. Showed no reduction in cardiovascular morbidity or mortality over 5 years
    2. (2013) Engl J Med 368(19):1800-8 +PMID:23656645 [PubMed]

Images: Related links to external sites (from Bing)

Related Studies (from Trip Database) Open in New Window