Why is omega-6 important?
The omega-6-fatty acid linoleic acid (LA, 18:2 n-6) is an essential fatty acid that is important for the skin, mucous membranes and cell surfaces. The omega-6 fatty acid is also precursor of hormone-like substances important in inflammation processes in the body.
Linoleic acid is the precursor of the other omega-6 fatty acids and is converted into arachidonic acid (AA, 20:4 n-6), among other things. We cannot make linoleic acid ourselves, so we need to absorb it though our food. The Norwegian recommendation is that linoleic acid should represent 2.5 energy percent of your diet.
Status in the population
Getting enough omega-6 fatty acids in today's diet does not pose a challenge, rather the opposite.
The ratio between omega-6 and omega-3
The ratio between omega-6 and omega-3 in the Norwegian diet is roughly 5:1. This is considered satisfactory, and omega-3 here includes both plant-based omega-3 and marine omega-3. The ratio is important because the omega-6 fatty acids and the omega-3 fatty acids compete for the same slots in the body. Modern agriculture and industrialisation have led to an increase in omega-6 in many types of foods, such as meat, eggs and dairy products. Recent research indicates that a high intake of omega-6 can lead to overweight and obesity. A further increase in the intake of omega-6 fatty acids is therefore not advisable.
Omega-6 in fish feed
Farmed salmon is the source of as much omega-6 today as omega-3, because of the increased inclusion of vegetable oils in fish feed. The levels of omega-6 in fish feed should not increase further if salmon is to maintain the favourable ratio between omega-6 and omega-3.