From Japan, With Krill
Krill is the name given to a large family of shrimp-like crustaceans belonging to the order Euphausiacea. These tiny invertebrates are also sometimes called euphausiids.
They can be found in every ocean in the world but the most popular Krill species is the Antarctic krill or Euphausia superba. This is the krill found in the Southern Ocean and is the species fished commercially in Japan and all the way up to Russia.
Krill is a staple, high-protein, low-fat food in Japan where it is called okiami. Okiami is a traditional delicacy in Japan, Taiwan and Korea where dried krill is preferred over frozen krill.
Krill is also eaten in Russian, Ukraine and Poland where it is sold as precooked mince and coagulated paste.
Krill caught from the ocean are also used for other purposes beyond human consumption. These small invertebrates are used as fish food in aquaculture farms, as bait in sport fishing and also expressed for oil to use in health supplements.
Other popular species of commercially harvested krill include the Pacific krill (Euphausia pacifica) and the Northern krill (Meganyctiphanes norvegica).
How Sustainable is Krill as a Food Source?
Krill is rich in proteins and while it is low in fat, it is actually a rich source of Omega-3 fatty acids. It also contains antioxidants even more than fish.
While only a small percentage of harvested krill finds itself into human diets (at least, outside Japan), there is a growing belief that krill should replace fish and other human protein source.
As global food sources slowly dwindle, commercial fishing in the oceans will increasingly become regulated. This means that our best source of protein will soon become scarce.
In addition, increasing levels of pollution including mercury and heavy metal poisoning are making fish unhealthy additions to diets. Therefore, a suitable alternative to fish needs to be introduced to our diets.
In many ways, krill is the right candidate for a fish substitute. It is just like shrimps but with a salty and stronger taste. The tail is edible and rich in Omega-3 fatty acids.
While krill is mostly safe from pollutants because of its small size and brief lifespan, the exoskeleton can still accumulate fluorides. For this reason, the exoskeletons are removed during preparation of krill for mass consumption.
If we are to replace the other seafood in our diet with krill, it would seem that there is a risk of depleting the stock of the crustacean in the oceans. However, this is very unlikely.
There are a number of reasons why widespread krill consumption is unlikely to place the invertebrate on the endangered list. For one, krill has the largest biomass of all creatures on the planet. In fact, the Antarctic krill which is only one of eight-five species of krill known has a biomass that is twice that of the global human population.
In addition, human consumption of krill is unlikely to shake up the food chain because krill harvesting from the oceans is arguable the best regulated seafood harvesting there is.
Krill Oil vs. Fish Oil
While krill is finding its way into restaurant menus now some may not find it tasteful. You can still enjoy the benefits of krill by choosing krill oil.
Quite a few studies have been done about the health benefits of krill oil but they have all been positive. Two important studies published by Canadian researchers studied the effects of krill oil on hyperlipidemia and cardiac diseases as well as on chronic inflammation and symptoms of arthritis.
In the first study, the results showed that in the management of hyperlipidemia, 1–3 g of krill administered daily was significantly more effective than daily doses of 3 g fish oil.
The study also established that a daily maintenance dose of 500 mg of krill oil was effective for lowering blood levels of LDL and triglycerides while increasing HDL levels and reducing the risk of cardiovascular disease.
In the second study, 300 mg of krill oil was found effective for relieving the symptoms of osteoarthritis and rheumatoid arthritis.
Krill oil contains omega-3 fatty acids, Vitamins A, D and E as well as the antioxidant, astaxanthin.
The structure of the Omega-3 fatty acids in krill makes them more absorbable than the Omega-3 fatty acids in fish oil. Studies show that the extent of absorption of krill oil fatty acids is 10-15 times those of fish oil.
Similarly, the antioxidant property of krill oil is 48 times more potent than that of fish oil. The improved antioxidant action is chiefly due to astaxanthin which is more powerful than known antioxidants such as Vitamin C and E.
There are 4 known antioxidants in krill oil. These include Vitamins A and E as well as the carotenoids, astaxanthin and canthaxanthin.
This combination of potent antioxidants gives krill oil a very strong antioxidant property. The table below shows a comparison between the antioxidant properties of krill oil and other common antioxidants including some of the antioxidants contained in the oil.
Antioxidant potency is measured by the ORAC (Oxygen Radical Absorbance Capacity) method.
ORAC Values (micromole per gram)
- Vitamin A – 1.25
- Vitamin E – 1.25
- Lutein – 8
- Fish Oil – 8
- Coenzyme Q-10 – 11
- Astaxanthin – 51
- Lycopene – 58
- Krill Oil – 378
Astaxanthin is a carotenoid antioxidant. It is a lipid-soluble pigment responsible for the colors of microorganisms, seafood and birds in which it is found.
This antioxidant protects the Omega-3 fatty acids in krill oil from oxidative damage from air and heat. It keeps krill oil from going bad and is the reason why krill oil never goes rancid while fish oil can.
Astaxanthin protects body tissues from damage by oxidative free radicals. It is believed to also protect the cardiovascular and immune systems as well as protect against inflammatory and autoimmune diseases of the nervous system.