Pure brands of fish oil are determined by industry standards based on three qualities: Contamination, concentration and oxidation levels. The Council for Responsible Nutrition (CRN), World Health Organization (WHO) and the International Fish Oil Standards (IFOS) each has its own testing standards, which set the international standard for pure fish oil.

Oxidation Levels

Oxidation tests performed by the Council for Responsible Nutrition determine the freshness of fish oil for consumer use. Fish oil turns rancid quickly, which in turn can cause side effects and symptoms such as belching and bloating. Vitamin E slows down rancidity and should be included in any quality fish oil supplement. CRN standards will be listed on fish-oil products if they were tested and passed the standard.

Concentration Levels

Quality fish oils must pass concentration-level tests that reach or exceed 60 percent combined concentrations of EPA and DHA. EPA and DHA are respectively eicosapentaenoic acid and docosahexaenoic acid, the primary fatty acids of omega-3 polyunsaturated fats. EPA and DHA's concentration levels should be listed on the supplement ingredients.

Contaminant Levels

Pure fish oil needs to be extracted from fish that are not heavily contaminated with chemicals within the environment. Since there are so few pristine waters remaining, most fish oils are required to be purified and distilled in order to be certified as pure fish oil. All internationally accepted standards for testing purity of fish for pollutants like PCBs, mercury, dioxins and furan ensure that a fish-oil product is certified with quality ingredients, and will be listed on the fish-oil supplement.

Brand Testing

Moreover, the Environmental Defense Fund (EDF) tests fish-oil brands for safety levels based on EDF standards. EDF has supplied a public list of fish-oil brands that have undergone their testing standards, and how each brand rated for purity, safety and quality. The full EDF purity list can be found at the EDF website: www.edf.org/page.cfm?tagID=16536.

Pure Brands vs. Worst Brands

The best brands recognized for providing quality fish-oil supplements are companies like Carlson Laboratories, Giant Eagle, Walmart, Walgreen's and Usuna. A few of the worst brands include Kmart, Omega Protein, Solaray and Rite Aid.

Source:

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