The trade in long chain omega-3 fatty acids is booming on the back of well-documented health benefits, and DHA and EPA, the most bioavailable sources for humans are being used as ingredients in dietary supplements and functional foods throughout the world. According to Frost & Sullivan, the global omega-3 ingredients industry is now worth US$1.6bn.
The most common source of EPA and DHA is oily fish, although vegetarian sources (from microalgae) are also available. Some 40 per cent of the omega-3 oils used in food and supplements are said to originate in Norway.
The new research project his being funded under a project called Norwegian Food from Sea and Land, and is being carried out jointly by the National Institute of Nutrition and Seafood Research (NIFES), Oslo University’s Department of Nutrition, Uppsala University, and the Centre for Clinical Studies in Bergen.
In addition to looking at the healthiest source, Livar Frøyland of NIFES and colleagues will be looking at whether the best oil comes from fresh fish or rancid. While it may seem obvious that fresh is better than old oil in which oxidation has occurred, no comparison has ever been documented.
The findings are expected to prove helpful to health authorities, which need independent documentation to give independent advice on the best types and formats of fish oil, and types that are best avoided.
“Consumers, the authorities and the industry are all interested in knowing more about how omega-3 from different products is absorbed into the body, as well as what kind of requirements should be stipulated in terms of freshness,” said Frøyland.
“Rancid fish oil smells bad and tastes so awful that no-one would want to swallow it. But if the fish oil is in capsules, it is impossible to smell if it is rancid or not. That is why it is important for us to examine whether rancid fish oil is less beneficial to health, or, at worst, harmful to anyone who takes it.”
Early trials
The planned research will involve mouse models and humans. However some early experiments have already been conducted in the lab at the University of Oslo, where the effects of different omega-3 sources on cells were investigated.
In one trial in particular omega-3 and antioxidants from Smartfish (originating from Marine Harvest Ingredients and sourced independently) were tested in juice.
Janne Sande Mathisen, R&D director at Smartfish, reports: “The tests show that fish oil from capsules caused oxidation of the cell membrane, even when antioxidants had been added and when the capsules still had over a year left before their expiration date. Juice containing omega-3, on the other hand, produced no oxidation.”