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Heart Smart Living
Heart Smart Living

Cardiologist, author, and heart health expert Dr. Sarah Samaan offers advice on how to live a heart smart life.

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Krill Oil or Fish Oil: What’s the Difference?

Omega-3 fatty acids are best known for their heart protective properties and their ability to lower triglyceride levels, but they also help to keep the skin supple and the eyes bright. Omega-3 fats are critical to the healthy development of the fetal brain, and some evidence suggests that omega-3s may even help improve mood disorders.

Cold-water fish, especially wild salmon, are chock-full of omega-3’s, and people who eat fish two to four times weekly are anywhere from 30 to 50 percent less likely to suffer heart attacks or strokes, as long as the fish isn’t fried.  For plant-based omega-3s, walnuts and flaxseed oil are reasonably good sources of an omega-3 fat known as ALA, although our bodies are able to use the omega-3 fats from fish (known as EPA and DHA) much more effectively.

If fish is not part of your weekly menu, fish oil is an easy and inexpensive way to get the omega-3 that your body craves. Just about any drugstore brand will provide reasonable amounts of the good stuff (a daily dose of about 300 mg of EPA and DHA combined works for most people). However, fish is not the only source of these beneficial fats.

Krill oil, which comes from tiny shrimp-like crustaceans, is aggressively marketed as a better alternative, since it reportedly contains more antioxidant ingredients than fish oil. However, at a cost of around one dollar per day, compared to about 10 to 15 cents for fish oil, is it really worth it? 

For all the efforts spent on promoting krill oil, there is actually very little hard data comparing it to fish oil. A 2011 Norwegian study published in the peer-reviewed journal Lipids investigated the effects of krill and fish oils on lipids and blood levels of inflammation. Overall, they found similar effects of both supplements, although it appeared that a smaller dose of krill oil was needed to achieve the same results seen with fish oil. Similar findings were reported in a German study published the same year in the journal Lipids in Health and Disease.

Although krill oil does appear to be more easily absorbed, it’s hard to justify the cost when fish oil is so inexpensive. If your concerns are environmental, you should know that there have been concerns about the sustainability of krill harvesting, and the potential effects on the marine ecosystem. The same can be said of certain forms of fish oil. To be safe, look for brands certified by the Marine Stewardship Council.

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Tags: Diet and Heart Health , Supplements

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About the Author


Dr. Samaan is an acclaimed cardiologist, writer, and heart health educator.