The earliest suggestions that certain 'fatty acids' (the building block of oils) might be, like vitamins, vital to health in small quantities were ridiculed by the scientific establishment: oils were viewed as simply a concentrated source of energy for the body and devoid of any role in health promotion.
Science has moved a long way since then: fatty acids have
been implicated in the healthy function and development of cells and tissues at
every stage of life. Two fatty acids in
particular, 'EPA' and 'DHA' omega-3s*, are the subject of an "impressive
documentation ... related to health benefits” with special reference to the
heart and cardiovascular system. Despite
this, "the cellular and molecular mechanisms for (EPA and DHA) action are
still insufficiently understood" (Gil).
It seems however that human beings aren't very efficient at
producing their own EPA and DHA.
Therefore, like vitamins, these omega-3s have a recommended daily intake. Because the aquatic food chain, based
on algae which produce EPA and DHA, is our only significant source of these
omega-3s, the recommended daily intake is set at two portions of fish per week,
one of them 'oily'*.
Around 50% of fish and seafood for human consumption is now
produced in aquaculture farms. Top of
the market value in this field is salmon, of which Scotland is one of the
leading producers (alongside Norway, Chile and North America).
Unfortunately, large-scale salmon farming in its current
form is proving problematic. Salmon are
carnivorous, but feeding fish on fish to produce fish is unsustainable, and
some two-thirds of the feed for farmed fish has been replaced with
vegetable-matter supplemented with ten percent fish-oil.
Salmon can make all the EPA and DHA they need for
themselves, so on a natural diet high in the omega-3s, they will accumulate the
oils in their flesh. They grow and live
quite happily on the low-fish diet they're given in farms, but are now failing
to provide the EPA and DHA nutritionists think the human consumers
need. In the last decade, omega-3 levels
in farmed salmon have halved.
Hardly surprisingly perhaps, scientists in the Institute of
Aquaculture at Stirling University have been collaborating with GM crop
scientists in Rothamsted Research in England to develop plant-based 'fish-oil'
for salmon farming.
Rothamsted has been busy the last few years creating and
field-testing successive GM version of 'camelina' oilseed plants, each with
increasing levels of omega-3s. Stirling University
has been busy running salmon feeding trials on the Rothamsted creations to see
if the fish grow well, stay healthy, cope with environmental stress, and
accumulate useful amounts of EPA and DHA in their flesh.
The most recent GM 'fish-oil' offering has seven inserted
genes plus a marker gene for identifying successfully-transformed cells. It contains over 25 percent of the required
omega-3s, and has proved "highly efficient" in achieving salmon with
human-friendly flesh. In short-term
salmon feeding trials, "only mild effects" on the metabolism of the
liver and intestine of young fish were noted.
The next phase, just started, is to see whether this GM
success story will hold true in real-life farms when the fish are fed the GM
oil diet until they reach market weight (about eight times the size of the
salmon in the preliminary experiments).
It also remains to be seen if the findings translate to other species of
farmed fish.
Using prime agricultural land to feed fish doesn't sound
like the most sustainable way to feed the world. As GM Watch points out:
"It is unclear why fish diets cannot be supplemented directly with non-GM algae, which is rich in omega-3 oils, rather than complicating the process by engineering plants to produce the oil, then extracting the oil, and feed the fish on that".
Algae fermenters
are already the source of omega-3s for infant formulae, dietary supplements,
pet foods, the food and beverage industries, and pharmaceuticals. ExxonMobile
is planning to produce 10,000 barrels of algae-based biofuels a day by 2025: a
suitable strain of algae has already been isolated and work on production in
outdoor ponds (using sunlight as the major energy input) is underway.
However, genetic engineers have dismissed this direct source
of omega-3s as having "biological and technical issues" which prevent
it from being cost effective. Oilseed
crops which already dominate global food oil production have a well-established
infrastructure for cultivation, harvest, processing, distribution and
marketing. Oilseeds don't contain EPA
and DHA, but they do contain a natural chemical precursor which, with a bit of
fancy metabolic engineering by genetic engineers, can be converted to the
required omega-3s. They are also
patentable, agrichemical industry friendly and biotech industry friendly.
OUR COMMENT
In the rush to stuff GM omega-3s into people for the sake of
their health, the actual, measured health of those people and of other,
non-human, consumers aren't getting much attention. This point will likely be ridiculed by the
scientific establishment, but the camelina has been metabolically engineered
with a string of artificial genes to produce large quantities of two substances
totally alien to it, plus all the necessary alien intermediate
biochemicals. EPA and DHA themselves are
bioactive compounds critically involved in key physiological functions, but
poorly understood. Harmful novel
by-products, such as omega-3 analogues, could be catastrophic to our long-term
health.
Brexit is likely to become an excuse to rush down the GM
fish-oil route. Suggest to your
regulators that some research funds could usefully be channeled into the
development of fish-oil alternatives which are truer to nature, easily
quality-controlled, non-GM, low impact on agriculture and on the natural
environment, and embedded in a circular economic and energetic system.
Also, check out COULD GM FISH-OIL WRECK THE ENVIRONMENT? - Coming soon, November 2018
*Note on fatty acids.
EPA is 'eicosapentaenoic acid', DHA is 'docosahexaenoic acid'. Chemically, these are different types of 'omega-3 long chain polyunsaturated fatty acids' sometimes referred to as 'LC-PUFAs'.
*Note on oily fish.
Oily fish include salmon, trout, mackerel, herring, pilchards and sardines. One 'portion' is 5 oz. or 140 grams.
SOURCES:
·
Angel Gil, et al., 2012, Systematic
reviews of the role of omega-3 fatty acids in the prevention and treatment of
disease, British Journal of Nutrition 107
· Javier Delgado-Lista, et al., June 2012, Long
chain omega-3 fatty acids and cardiovascular disease: a systematic review,
British Journal of Nutrition 107, S2
· M. B. Betancor, et al., January 2015, A
nutritionally-enhanced oil from transgenic Camelina sativa effectively replaces
fish oil as a source of eicosapentenoic acid for fish, Scientific Reports
·
Naemi Tejera, et al., January 2016, A
Transgenic Camelina sativa Seed Oil Effectively Replaces Fish Oil as a Dietary
Source of Eicosapentaenoic Acid in Mice, The Journal of Nutrition: Nutrient
Physiology, Metabolism, and Nutrient-Nutrient Interactions
·
M. Sprague, et al., February 2016, Impact
of sustainable feeds on omega-3 long-chain fatty acid levels in farmed Atlantic
salmon, 2006-2015, Scientific Reports
·
Mónica
B. Betancor, et al., July 2016, Nutritional evaluation of an EPA-DHA
Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon
(Salmo salarL.), PLOS ONE
·
Mónica
B. Betancor, et al., April 2017, An oil containing EPA and DHA from
transgenic Camelina sativa to repla ce marine fish oil
in feeds for Atlantic salmon (Salmo salar L.): Effects on intestinal
transcriptome, histology, tissue fatty acid profiles and plasma biochemistry,
PLOS ONE
·
Mónica
B. Betancor, et al., 2018, Oil from transgenic Camelina sativa
containing over 25% n-3 long-chain PUFA
as the major lipid source in feed for Atlantic salmon (Salmo salar),
British Journal of Nutrition 119
·
Steve Connor, First nutrient-enriched GM
crops could be grown in the UK with months, Independent, 24.01.14
·
Algae: our original omega-3 source,
www.wur.nl
·
Dietary fish recommendation, www.nhs.uk
·
Sarah Knapton, Genetically modified crop
successfully fed to salmon say scientists, Telegraph, 28.01.18
·
Rothamstead GM omega-3 plants suitable for
farmed fish, http://the aquaculturists. blogspot.com/2015/01
·
ExxonMobil News,
https://energyfactor.exxonmobil.eu, 19.07.18
·
GM fish food intended to prop up
unsustainable fish farming, GM Watch 01.08.18
·
Pallab Ghosh, Trial to test if GM fed salmon
are more nutritious, BBC 1.08.18
·
Could GM fed salmon be more nutritious than
non-GM fed salmon?, Food Magazine,
2.08.18
·
It's tiny, green, and could be the future of
biofuels, ExxonMobil advertisement, Metro 26.09.18
Photo: Creative Commons
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