Krill may top fish oil as a source of omega-3s

Krill oil is extracted from tiny Antarctic crustaceans that serve as food for baleen whales, fish and some seabirds. Some of the supplement’s manufacturers say krill is superior to fish oil as a source of omega-3 fatty acids because its omega-3s may be more easily absorbed by the body -- a claim supported by preliminary evidence from lab and animal studies. In addition to eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA) -- two omega-3s that are also found in fish oil -- krill oil is rich in vitamins A and E, protein and potent antioxidants. Some environmentalists caution against krill harvesting for supplement use, as the organisms’ numbers have been declining in Antarctic waters for several decades.

Uses: People use krill oil for many of the reasons they take fish oil -- to prevent or treat high cholesterol, heart disease, arthritis, liver disease, cancer and premenstrual syndrome.

Dose: 1 to 3 grams a day. It is often sold in soft-gel form.

Precautions: Krill oil can trigger allergies in people allergic to shrimp or other shellfish. Like fish oil, krill oil can slow the blood’s clotting time and amplify the effects of blood-thinning drugs.

Research: Very little human research has been conducted using krill oil, so it’s too early to draw conclusions about its clinical effectiveness. In two clinical trials, krill oil intake was effective in managing PMS and hyperlipidemia, or high blood levels of cholesterol and other fats. However, both studies investigated a patented version of the supplement and were paid for in part by the manufacturer.

Dietary supplement makers are not required by the U.S. government to demonstrate that their products are safe or effective.