There are literally not enough fish in the sea when it comes to recommended daily intake of omega-3 fatty acids. New research has shown that seed oil from genetically modified camelina plants is as good as fish oil at increasing two key types of omega-3 in the blood, pointing the way to a sustainable alternative source.
A slippery problem
Omega-3 fatty acids are a diverse group of fats that are important for health, which our body can’t make and must get them instead from food. Some omega-3 fatty acids, namely eiosapentaenoicacid (EPA) and docosahexaenoic acid (DHA) are vital parts of our cell membranes where they influence the activities of proteins such as hormone receptors and are the starting material for making substances that control the immune system.
The UK government has made recommendations for daily intake of EPA and DHA to maintain health; consume two portions of fish per week, one of which should be oily. Oily fish such as salmon, mackerel and sardines are the main source of EPA and DHA, together with smaller amounts in meat and dairy products.
However, most UK adults only consume about half the recommended amount of oily fish, while those who exclude animal-derived foods from their diet have intakes close to zero. EPA and DHA intakes in children are about 10% of recommended levels.
The poor adherence to recommendations for EPA and DHA intakes is due to dislike of the taste of oily fish, the cost of oily fish and concerns about contamination with environmental pollutants. Moreover, global fish stocks can only provide 16% of the world population’s omega 3 needs.
Overall, there is a clear need for sustainable and scalable alternatives that are broadly acceptable across the population.
Plants not the answer – until now
Plants are another source of omega-3, however they provide it in a form known as alpha-linolenic acid (ALA) which can be used to a very limited extent by the body to make EPA and DHA. This has been shown to be an inadequate alternative to consuming EPA and DHA.
Now a study, led by Professor Graham Burdge in collaboration with Professor Johnathan Napier at the Rothamsted Research Institute, and published in The British Journal of Nutrition, has found that the seed oil from genetically modified strain of Camelina sativa can directly substitute for fish oil as a source of EPA and DHA in the human diet.
Production of this modified camelina plant could easily be scaled up, with no greater impact on the environment than any other oil seed crop, to meet the health needs of the entire population – including vegans, vegetarians and those who choose not to eat oily fish. By reducing pressure on fishing stocks it could also help protect the marine environment.
What did the study find?
The researcher conducted two studies. The first showed absorption of EPA and DHA from a single meal was as good if they were provided by camelina oil and when consumed in fish oil.
In the second study, thirty-one healthy participants were randomly assigned to two groups, with the first group taking a fish oil supplement daily for eight weeks and the second group taking oil from modified camelina. They then had a six week ‘wash out’ period where they took neither supplement, before the two groups swapped to take the other oil, again daily for eight weeks.
For both groups, their daily dose was calculated so that their omega-3 intake matched the amount recommended by UK health guidelines (450mg EPA and DHA per day in adults).
The researchers found comparable amounts of omega-3s EPA and DHA in the blood of participants who had taken the fish oil and those who had taken the camelina oil.
Professor Graham Burdge said: “These results show that seed oil from camelina plants that have been genetically modified to produce these two omega-3 fatty acids, could provide a sustainable plant-based alternative source of EPA and DHA that is as good as fish oil.
“This work was entirely supported by British tax payers through the Biotechnology and Biological Sciences Research Council with no commercial input. Moreover, this globally unique plant could be a world beating novel crop for British farmers.”
Posted on Friday 20 November 2020