A reader asked for a summary of the benefits of krill oil.

Most of the published literature is based on animal studies. But several researchers have studied humans.

First, some background.

  • Krill (photo) are shrimp-like crustaceans (1 to 6 cm long) that live in the ocean, where they feed mainly on phytoplankton.
  • They’re near the bottom of the food chain and are eaten by whales, seals, penguins, squid, and fish.
  • Krill oil contains omega-3 fatty acids, which is the main reason it’s becoming popular as a nutritional supplement.

Effect on omega-3 fatty acids

  • 76 overweight and obese men and women were treated with 2 grams/day of krill oil, fish oil, or control (olive) oil for 4 weeks.
  • Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) blood levels increased significantly more with krill oil and fish oil vs placebo.
  • There was no significant difference in systolic blood pressure with krill oil vs the other treatments.


  • In 120 patients with high cholesterol levels, Neptune Krill Oil 1-3 grams per day reduced blood sugar levels, total cholesterol, triglycerides, and LDL (bad) and HDL (good) cholesterol, compared to fish oil 3 grams daily and placebo.
  • It was significantly more effective than fish oil for reducing glucose, triglycerides, and LDL levels.

Management of premenstrual syndrome and dysmenorrhea

  • The effectiveness of Neptune Krill Oil was compared to omega-3 fish oil in 70 patients.
  • Women taking krill oil consumed significantly fewer pain pills during the 10-day treatment period than women receiving omega-3 fish oil.

The bottom line?

No. This is not an advertisement for any particular company. But where Neptune supported the research, they deserve recognition.

Taking krill oil increases EPA and DHA levels. In 1 study, the resulting levels were higher with krill oil compared to fish oil or olive oil, although no difference in a clinical outcome (blood pressure) was found. In another study, krill oil had a positive effect on blood sugar levels and cholesterol levels.

Whether any of this results in a lower risk of any disease associated with prolonged high blood pressure, high cholesterol levels, or high blood sugar levels remains to be seen.

Also, in 1 study women took fewer pain pills during their menstrual period.

8/7/10 18:57 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at www.Vicus.com, a complementary and alternative medicine website.