Fish oil capsule. (Photo: Nofima)
Enriched foods are a suitable way of consuming omega-3: study
Wednesday, February 22, 2012, 22:30 (GMT + 9)
A new study shows that you get just as much omega-3 whether you take capsules or eat enriched food. The next big question is: How much omega-3 do you need?
"We can see that just as much omega-3 is absorbed into the bloodstream regardless of whether we take in these long-chain marine fatty acids in capsules, enriched fruit juice or enriched fish paté," explains Senior Research Scientist Bente Kirkhus of Nofima Mat, the Norwegian Institute of Food, Fisheries and Aquaculture Research.
In the study, 159 healthy men and women were randomly divided into four groups. One group ate 34 g of salmon paté, another drank 500 ml of enriched fruit juice and a third took three capsules of concentrated fish oil.
Over a seven-week period, they all had a daily intake of 1 g of omega-3, which includes the important long-chain fatty acids EPA and DHA.
The fourth group was a control group and received no omega-3 supplements.
"In this study, which was an intervention study, we chose a dose of 1 g of omega-3. This corresponds to one spoonful of cod liver oil, and previous studies have shown that this quantity reduces the risk of heart attack among people with cardiovascular disease or who are in the risk zone for developing cardiovascular disease," says Kirkhus.
After the seven weeks, the researchers measured the omega-3 level in blood plasma. They found that EPA and DHA levels had increased approximately equally in all three groups.
However, in spite of the fact that intake of both was the same, EPA increased by 134 per cent on average, but DHA only 40 per cent.
"Both the group that tested the fruit juice and the group that tested the salmon paté liked these products, so they can be a good alternative to capsules. Those who don't like fish or don't want to take capsules can certainly be advised to drink an omega-3-enriched fruit juice," says Kirkhus.
As well as testing the level of omega-3 in blood, the researchers also measured the level of fatty substances, inflammatory markers and markers for oxidative stress (cell damage). These markers can provide indications of the risk of cardiovascular disease.
It was found that, for the healthy people taking part in the study, the intake of omega-3 had no effect on the risk markers. The levels were the same as for those in the control group.
There is good evidence that fish and fish oil that are rich in omega-3 reduce the risk of cardiovascular disease. The health effects of omega-3 are well known, and the range and sales of omega-3 products increase every year.
It is relevant to ask how much omega-3 healthy people need in order to protect against cardiovascular disease. At present, recommendations range from 200 mg to 1 g per day.
Bearing in mind that long-chain marine fatty acids are a limited resource, it is important to clarify what doses are needed by different population groups.
"We need more research into this to find the answers, so that we can make the best possible use of the world's limited omega-3 resources," concludes Kirkhus.
By Wenche Aale Hægermark/Nofima