The upcoming October issue of Functional Ingredients magazine features an article by former managing editor James Townsend on the state of the omega-3s market. But not all omega-3s are created equal, and in the maritime segment of the omega-3s world, the segment with the largest amount of scientific research behind it, there is a divide: Does your source material have a backbone, or no?

We're talking here about krill versus fish oil. Given that the two ingredients are lumped together in the $739 million fish and animal oils market, it's easy to think of them as two pieces battling for the same pie.

Scratch a little beneath the surface, though, and what you will find is two interesting ingredients both backed by strong nutrient profiles and solid science.

How are they the same? How are they different? What is the state of the scientific research?

FI went fishing for answers, and here is what we found:

Where Do They Come From?
Krill are shrimplike crustaceans that are a dietary staple for whales, small fish, and seabirds found in all oceans in the world. There are some 85 species of krill, but the species that swims in the Southern Ocean off of Antarctica, Euphausia superba, is the one being harvested for human consumption.

Fish oils are usually sourced from oily cold-water fish such as macherel, anchovies and sardines. The sources depend on the ingredient supplier.

For example, Ocean Nutrition Canada, based in Nova Scotia, obtains its fish oil from anchovy (95-99%) and sardine (1-5%) caught off the coast of South America. Nordic Naturals fishes the Norwegian Sea for arctic cod and Norwegian herring (40%) and the South Pacific for Pacific sardine and Peruvian anchovy (60%).

Both fish and krill are selling strong. In 2008, Nutrition Business Journal pegged the fish and animal oils market at $739 million in 2008 on 18 per cent growth. NBJ's most recent market estimates won't be available until September.

John Schoonbrood, president of krill-oil supplier Azantis Inc, sees strong and growing interest in krill, the relative newcomer on the market.

"I expect krill oil will capture 20 per cent of the omega-3 market within the next five years," Schoonbrood said. Azantis Inc currently has about 25 per cent of the krill oil market share in the US.

What is Their Nutrient Composition?
Although both fish and krill oils contain DHA and EPA, they have unique nutritional compositions.

Krill oil generally provides 14% EPA and DHA, and about 0.2% astaxanthin. Natural fish oil contains about 30% EPA and DHA, plus 0.25-0.50% vitamin E, added as an oil stabilizer.

So the upside to fish oil is that it has higher ratios of omega-3s. The upside to krill oil is its more efficient transport into the cells of the human body.

In fish oil, the omega-3 molecules are attached to triglycerides, which means they must undergo hydrolysis before being absorbed into cells. Krill, in contrast, is attached to phospholipids.

"Our cell walls contain fats in the phospholipid form," explains Kantha Shelke, principal at Chicago-based food and nutrition think tank Corvus Blue. "The phospholipid structure of the omega-3s in krill oil therefore makes them more rapidly absorbable and allows for easier entry of the omega-3s into our cells and on to the mitochondria and nuclei. The rapid absorption has an added benefit for consumers: There is virtually no aftertaste or fishy reflux that some experience with fish oils."

The conjugation of phospholipids — mainly phosphatidylcholine — with DHA and EPA gives krill oil an edge over fish oil in a number of ways, Shelke says. "The phospholipids, by virtue of their connection with omega-3s, are exactly right for proper brain function. Furthermore, they are a part of the eicosanoids system — an extremely important hormone-messenger system in the cells of the body."

For Schoonbrood at krill-oil supplier Azantis, both ingredients have their benefits.

"In summary, yes both fish oil and krill oil are omega-3 products, but that's where the similarity ends," Schoonbrood says. "It's like apples and oranges. Apples are good, oranges are good. There is a place for both."

What Does the Science Say?
To date, three placebo-controlled, double-blind human clinical trials have been conducted on krill oil. The studies have shown its ability to reduce menstrual symptoms, reduce lipid and blood glucose levels and combat inflammation.

A 2003 study at the University of Montreal found krill oil to be superior to fish oil in the treatment of premenstrual syndrome (PMS) and dysmenorrhoea (DM).¹

A 2004 study at McGill University found 1-3g/day of krill oil was more effective in reducing lipid and glucose levels than either fish oil or placebo.²

Then, a 2007 study at University Health Network Toronto found that intake of krill oil for seven to 14 days significantly reduced C-reactive protein levels in patients with cardiovascular disease, rheumatoid arthritis and/or osteoarthritis, when compared to placebo.³

More than 8,000 clinical human studies have been published on fish oil, documenting its benefits in everything from heart health to arthritis to macular degeneration — just to name a few. To read more about some of the more compelling studies, visit the website of GOED, the Global Organization for EPA and DHA Omega-3s.

References
1. Sampalis F, et al. Evaluation of the effects of Neptune Krill Oil on the management of premenstrual syndrome and dysmenorrhea. Altern Med Rev 2003;8(2):171-9.
2. Bunea R, et al. Evaluation of the effects of Neptune Krill Oil on the clinical course of hyperlipidemia. Altern Med Rev 2004;9(4):420-8.
3. Deutsch L. Evaluation of the effect of Neptune Krill Oil on chronic inflammation and arthritic symptoms. J Am Coll Nutr 2007;26(1):39-48.