Autumn 2014 True Natural Health Magazine – Your Questions Answered
By Roger French
QUESTION: Krill oil – is it OK? Where do krill spend most of their life – absorbing chemicals in the water near the surface or deep in the ocean where it is cleaner?
As you know, K. R., krill are animals and are not part of a plant-based way of eating. However, there is so much promotion of krill oil that it interesting to find out just what they are and whether they are likely to be contaminated with toxic chemicals.
Krill are primary or significant food sources for whales, seals, penguins, many other species of birds including albatross, and squid and fish. A blue whale can consume up to four tons of krill per day, and other baleen whales can also consume tons per day. Krill themselves feed on phytoplankton and on the algae that accumulates under sea ice.
Believed to be the largest population of any species on Earth, krill often aggregate in swarms of millions or even billions. Part of the reason that Antarctic krill are so numerous is that the waters around Antarctica are very rich in phytoplankton and the algae growing under sea ice.
Krill are also found in the oceans off Vancouver, Russia, Ukraine and Japan, and are important components of many ecosystems.
The West Antarctic Peninsula is one of the most rapidly warming areas in the world and consequently has lost a lot of sea ice over the past few decades. As a result, krill populations as well as populations of krill-dependent Adelie penguins are declining.
Commercial harvesting is also contributing to the decline, and there is concern that it could threaten the species that depend on krill, including whales. In 2010 part of the southern krill fishery had to be closed due to the catch limit for that area being reached.
Commercial uses of krill include food for salmon farming, home aquariums, human food (as in Japan) and the current exploding demand for krill oil capsules.
The basis of the popularity of krill oil is that, like fish oil, it contains the omega-3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). It also contains a carotenoid called astaxanthin, which is an effective antioxidant.
How polluted might krill be? Krill oil has some advantages over fish oil. Firstly, krill oil is less likely to be polluted because krill live in the relatively pristine waters of the Southern Ocean. Secondly, krill lead shorter lives than salmon, tuna and mackerel, so have less time to absorb toxin chemicals, such as methyl-mercury and PCBs, which are well known contaminants of tuna. However, good quality fish oil is normally distilled, which removes these chemicals.
Unfortunately, many of the cheaper brands are using krill from the warmer, more polluted waters of the North Pacific. If you are going to buy expensive krill oil supplements, you would want the best quality.
In spite of the above facts, even good quality krill oil may have some degree of contamination with methyl-mercury and other pollutants. Pollution exists in every ocean, even the Southern Ocean close to Antarctica. It’s unlikely to find any marine source that is completely free of contamination, and this includes krill habitat.
If you are taking krill oil, take it as directed on the label or as prescribed by a doctor; don’t take larger doses or for longer than recommended. If you have allergy to seafood, don’t take it at all. People taking anticoagulants in particular should notify their doctor prior to considering taking krill oil, and don’t take it within at least two weeks prior to surgery. Because some drugs can interact with krill oil, it is wise to advise a doctor about all medications and supplements that you take.