Omega-3 Fish Oil Supplements: Beneficial, Harmful or Waste of Money?

October 12, 2018   /
omega 3 fish oil supplements

The bottom line

Because the evidence on fish-eating and various health benefits is strong, RDs should always take a food-first approach and work with patients to find ways to incorporate more seafood into their diet, with a goal of 2 to 4 ounce servings of fatty fish, such as salmon or sardines, each week. For those who do not or cannot eat fish, RDs should work with them to incorporate plant sources of omega-3s, such as walnuts, flax or hemp seeds, and leafy green vegetables.

Even though the evidence on using omega-3 from fish oil to reduce the risk of CVD is not as strong as once thought, it does not appear to have harmful effects for most people. Because there are potential benefits for other aspects of health, it seems wise to recommend a low dose of 1-2 grams/day for those who may benefit, with higher doses on a case by case basis.

As with other nutritional supplements, omega-3 supplements are not regulated by the FDA. Patients should be educated about how to choose higher quality supplements that are third-party verified or tested for quality and consistent dose.


  1. Clarke TC, Black LI, Stussman BJ, Barnes PM, Nahin RL. Trends in the use of complementary health approaches among adults: United States, 2002–2012. Natl Health Stats Reports. 2015;(79):1-16.
  2. Balk EM, and Lichtenstein AH. Omega-3 fatty acids and cardiovascular disease: summary of the 2016 Agency of Healthcare Research and Quality Evidence Review. Nutrients. 2017;9(8):865.
  3. Aung T, Halsey J, Kromhout D, et al. Associations of omega-3 fatty acid supplement use with cardiovascular disease risks: meta-analysis of 10 trials involving 77 917 individuals. JAMA Cardiol. 2018;3(3):225–234.
  4. Siscovick DS, Barringer TA, Fretts AM, et al. Omega-3 polyunsaturated fatty acid (fish oil) supplementation and the prevention of clinical cardiovascular disease: a science advisory from the American Heart Association. Circulation. 2017l135(15):e867-e884.
  5. Lorente-Cebrián S, Costa AG, Navas-Carretero S, et al. An update on the role of omega-3 fatty acids on inflammatory and degenerative diseases. J Physiol Biochem. 2015;71(2):341-9.
  6. Calder PC. Marine omega-3 fatty acids and inflammatory processes: effects, mechanisms and clinical relevance. Biochim Biophys Acta. 2015;1851(4):469-84.
  7. Mocking RJ, Harmsen I, Assies J, Koeter MW, Ruhe HG, Schene AH. Meta-analysis and meta-regression of omega-3 polyunsaturated fatty acid supplementation for major depressive disorder. Transl Psychiatry. 2016;15(6):e756.
  8. Bos DJ, Oranje B, Veerhoek ES, et al. Reduced symptoms of inattention after dietary omega-3 fatty acid supplementation in boys with and without attention deficit/hyperactivity disorder. Neuropsychopharmacology. 2015;40(10):2298-306.
  9. Liu J, Cui Y, Li L, et al. The mediating role of sleep in the fish consumption–cognitive functioning relationship: a cohort study. Sci Rep. 2017;7(1):17961.
  10. Külzow N, Witte AV, Kerti L, et al. Impact of omega-3 fatty acid supplementation on memory functions in healthy older adults. J Alzheimers Dis. 2016;51(3):713-25.
  11. Bhargava R, Kumar P, Phogat H, Kaur A, Kumar M. Oral omega-3 fatty acids treatment in computer vision syndrome related dry eye. Cont Lens and Anterior Eye. 2015;38(3):206-10.
  12. Bhargava R, Kumar P. Oral omega-3 fatty acid treatment for dry eye in contact lens wearers. Cornea. 2015;34(4):413-20.
  13. Georgiou T, Neokleous A, Nicolaou D, Sears B. Pilot study for treating dry age-related macular degeneration (AMD) with high-dose omega-3 fatty acids. PharmaNutrition. 2014;2(1):8-11.
  14. Brasky TM, Darke AK, Song X, et al. Plasma phospholipid fatty acids and prostate cancer risk in the SELECT Trial.  J Natl Cancer Inst. 2013;105(15): 1132–41.
  15. Brasky TM, Till C, White E, et al. Serum phospholipid fatty acids and prostate cancer risk: results from the prostate cancer prevention trial. Am J Epidemiol. 2011;173(12):1429-39.
  16. Mason RP, Sherratt SCR. Omega-3 fatty acid fish oil dietary supplements contain saturated fats and oxidized lipids that may interfere with their intended biological benefits. Biochem Biophys Res Commun. 2017;483(1):425-29.