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What is the difference between fish oil and flax seed oil?

Omega-3 fatty acids fall into two major categories: plant-derived (flaxseed) and marine-derived (fish). This is often confusing for physicians and patients, and many think the two are interchangeable. Flaxseed oil contains alpha-linolenic acid (ALA) which can be partially converted to EPA and DHA, but that conversion is somewhat slow and can be inhibited by lifestyle and health factors. Research shows that approximately 5% of ALA converts to EPA, and just 1% converts to DHA, under optimal conditions. While flaxseed and flaxseed oil may contain many health-promoting benefits, they do not provide the necessary amounts of EPA and DHA.

What is the difference between fish oil and krill oil?

Several companies are selling krill oil supplements as a source of omega-3s. Krill are shrimp-like crustaceans that are a crucial link in the marine food chain, and concerns about the ecological impact of increased krill fishing has resulted in a ban on this practice on the U.S. West Coast, and strict limits in Norway and Antarctica. In contrast, fish oil supplements are predominantly produced from sardines and anchovies—species that are currently in abundant supply, fished well below mandated limits, and considered ideal for sustainability, given their short reproductive cycles. Fish oil is not only a more sustainable source for omega-3 supplements, it also provides a higher concentration of omega-3, is more molecularly stable, and is backed by more science than krill oil. Fish oil—when manufactured according to international quality standards—has a proven record of efficacy, purity, safety, and sustainability, and is backed by several thousand published studies.

What is the difference between fish oil and eating fish?

Many people are justifiably concerned about mercury levels and other environmental toxins in fish, especially larger species. Nordic Naturals fish oils provide you with all the benefits of the omega-3s EPA and DHA, without the risk of toxins found in fish. The fish oil used in every batch of our products is tested by independent laboratories and consistently delivers exceptional results, surpassing the strictest international standards for fish oil purity, freshness and potency. Certificates of Analysis are available on our website; simply enter your lot number to view the certificate for your specific bottle.

Will fish oil or EFAs interfere with my medical condition or medications I am taking?

Generally, no, but we suggest that you consult with your health care professional before taking fish oil if you are allergic to iodine, use blood thinners, take high doses of aspirin, or are anticipating surgery.

What is the difference between fish oil and cod liver oil?

Cod liver oil is extracted from cod livers, whereas fish oil is extracted from the body flesh of fish. While both are good sources of the omega-3s EPA and DHA, they provide different ratios—cod liver oil generally contains about 9% EPA and 14% DHA, whereas fish oil generally contains about 18% EPA and 12% DHA.