• Purity: Does the fish oil offer third party test results for purity and freshness. A third-party certificate of analysis indicates the levels of purity from environmental toxins, and the oxidation level (or freshness) of the oil.
  • Manufacturing standards. Is the fish oil manufactured according to international quality standards?
  • Smell and taste. Does the fish oil smell or taste fishy? If so, the fish oil has most likely been exposed to oxygen and is becoming rancid. Rancid (oxidized) oils should be avoided, as they yield less-than-healthy effects. Avoid fish oils that have really strong flavorings added to them because they are most likely trying to hide the fishy flavor of rancid oil.
  • Triglyceride molecular form. Research has shown that triglyceride form omega-3s are up to 70% better absorbed than synthetic ethyl ester omegas.
  • Supportive scientific research to prove the efficacy of the fish oil brand.
  • Sustainable fishing practices. Any environmentally responsible fish oil manufacturer should offer transparency into their fishing practices.