Wednesday, 2 January 2013

Krill vs Green-Lipped Mussel

Every so often I hear of amazing claims made by suppliers of supplements and health products that are almost too good to be true that invariably I am prompted to investigate further. Two such products are krill oil and green-lipped mussel oil. Both are extracted from marine wildlife species and both are highly prized for their oils which are extracted from their bodies for the purposes of making these supplements.  However, many commercial companies promoting the 'amazing' health benefits of these oil supplements have created a demand for such products that many environmentalists and eco-warriors are understandably concerned about the depleting stocks due to over-fishing. Though strict guidelines are now in place to limit the worst excesses and the unregulated manner of fishing in open seas and to ensure a sustainable population of these wildlife species, there is still a lack of scientific evidence to support the health benefits of these oil supplements to warrant the level of commercialism that has arisen as a result of the many claims that have been made. So exactly what are these claims?
Krill - a crustacean found in the Antarctic
ocean and harvested for its oil as a health
supplement but they are a vital food source
for other marine wildlife
Both krill oil and green-lipped mussel oil are relatively new to the market (they have been sold commercially since the early 1960s which is new in terms of the long-established supplements industry). Given this fledgeling market, studies are therefore limited so it is incredibly difficult to judge the validity of the claims but equally, it is also difficult to disprove any of them! Both oils are high in important fats, notably the essential fatty acids (EPA or eicosapentaenoic acid and DHA or docosahexaenoic acid). The numerous benefits of essential fatty acids have been discussed at length in an earlier post (see 'The Fats of Life' posted July 2012). For krill oil in particular, the health benefits range from confering protection againsts diseases such as heart disease, high blood pressure, cancer, stroke and depression in addition to  lowering levels of  'bad' cholesterol or low density lipoptrotein or LDL cholesterol. Higher doses of 2-3 grams daily also appears to significantly reduce levels of triglyceride, another type of blood fat associated with heart disease and other conditions when present in high levels. There is some evidence that taking 2 grams daily of krill oil might reduce symptoms of PMS but results from these studies are highly questionable as they were generated from poorly designed studies yielding unreliable data. There is probably better evidence of the benefits in inflammation given its ingredients (EFAs are potent anti-inflammatory agents) so conditions such as arthritis may well benenfit from these types of supplementation. However, there is still limited scientific evidence, but this is also true of all supplements.
The green-lipped mussel - farmed for its
oil in an industry that is heavily regulated
but highly profitable for the industry
The additional ingredient in krill oil is a substance called astaxanthin. This is a highly potent antioxidant that prevents the oil from going rancid. Antioxidants are substances, many of which are found in nature which prevent oxidation of biological and chemical processes. Oxidation is associated with things like food spoilage, ageing and disease states in the human body. We do however have a series of inate antioxidant processes in our bodies to combat the effects of oxidation, not to mention healthy diets and lifestyles which do their part in mitigating this so whether extra supplementation of antioxidants is needed remains entirely debatable.
  Green-Lipped Mussel

  • from the crustacean species Euphasia superba
  • lives in the Antarctic oceans near Northern Europe
  • largest biomass in the world feeding on algae (phytoplankton) which live under the icebergs of the Antarctic
  • krill is a very important food source for other marine wildlife, particularly the Baleen whales, mantas, whale sharks, penguins and seals
  • krill is frequently used as food for many fish farms particularly for salmon
  • China is now sending a fleet to the Antarctic waters to harvest krill as part of a 5-year plan to study the possibilities of using krill to feed farmed fish
  • krill fishing remains controversial as there is conflicting and limited evidence on its impact on sustainable populations whilst new harvesting technologies are being investigated 
  • from the mollusc species Perna canaliculus
  • endemic to the ocean waters off the coast of New Zealand
  • feeds on algae (phytoplankton) in the ocean waters of the Antarctic
  • young mussels (spats) are now farmed in hatcheries in a growing aquaculture industry
  • a heavily regulated industry now exists for green-lipped mussel fishing and cultivation so there is lesser concern about over-fishing about this marine wildlife compared to krill
  • a staple food of the indigenous Maori people who traditionally have healthier profiles and lower incidence of heart disease, cancer and other diet-related illnesses of the Western world. The green-lipped mussel oil supplements market was entirely driven by this observation

Reasons for fishing
  • purity of the fish (location of their habitats). There is relatively low pollution in the deep waters of the Antarctic ocean and the shore lines of New Zealand (green-lipped mussels are found below the low tide line)
  • both krill and green-lipped mussels are filter-feeders but because they feed deep in the oceans this ensures the relative purity of their oils compared to other fish oils such as cod-liver oil. Both krill and green-lipped mussels are at the bottom of the food chain and feeding in relatively clean waters ensures that their bodies are devoid of traces in heavy metals such as cadmium and mercury, as well as other pollutants, biotoxins and bacteria which can be present in fish which are higher up in the food chain and feed in relatively polluted waters
  • feeding on phytoplankton which have high levels of antioxidants enables these organisms to concentrate them in thier own bodies
  • the concerns over rancidity with other fish oils and the purported advantages of astaxanthin in krill
  • numerous health benefits claimed for both krill oil and green-lipped mussel oil
  • concerns about over-fishing (especially krill, in recent years) is alleged thought to be unjustified citing that the greatest concern to krill is the melting of the ice due to climate change (algae, the food source for krill is located underneath this ice)
Factors to consider
  • lack of evidence regarding the many health claims made
  • allergy to seafood - not suitable for the many people who cannot tolerate seafood. Krill oil and green-lipped mussel oil may also interact with medicines or other supplements
  • fishing for krill and green-lipped mussels contributes to environmental damage by creating and sustaining a demand for these products. If you are concerned, take plant antioxidants such as flaxseed oil or vegetarian alternatives (particularly algae-based omega-3 oils made by the Nethelands company Royal DSM N.V) - the marine wildlife will thank you for it
  • there are plenty of other ways to improve your fatty acid intake and measures to prevent illness instead of dessimating the marine wildlife resources and the important ecosystemts of the Antarctic ocean
  • do not buy into the marketing hype of manufacturers of these oils - they will always be biased. Humans have survived for much longer than the businesses that harvest and farm these marine wildlife species. A predisposition to certain diseases is dictated by greater and more powerful factors (such as genetics and a reckless lifestyle) that cannot be simply addressed or overcome by taking supplements of oils extracted from precious species that are vital to other marine wildlife
  • there are more pressing concerns of the 21st Century which will determine the very survival of humans such as climate change and over-population which is placing a huge strain on the Earth's natural resources, irreversibly changing the landscape, impacting on biodiversity and destroying important ecosystems. We do not need krill oil or green-lipped mussel oil for our survival
If you are concerned about over-fishing of these species, you can always campaign by writing to The Commision for the Conservation of Antarctic Marine Living Resources (CCAMLR)  which was established in 1982 with the objective of conserving Antarctic marine life. You can find more information about their work, campaigns and regulation on