Question: Which foods are good sources ?

Answer: The most readily available source of Omega 3s usable by the body are those found in oily fish and seafood. These include salmon, mackerel, kippers, fresh tuna, sardines, herrings. crab and mussels. The Omega 3s in these foods have long scientific names, but are shortened to EPA and DHA, and are also known as long chain (LC) essential fatty acids. There are also short chain (SC) Omega 3s from non-fish sources that the body can use but less well ie. you need to eat much larger quantities than for LC sources. These include hemp seeds, linseed, walnuts, and the oils made from these, as well as soya beans and associated products eg tofu.

Question: How much should I be eating ?

Answer: The current guidelines (Food Standards Agency, 2004) advise intake of up to 4 portions of oily fish per week for the general population, but this is reduced to 2 portions per week for women of childbearing age due to contamination concerns for mercury and dioxins. Recently it was suggested that these guidelines translate to an intake of 0.45 to 0.9 g of long chain Omega 3 per day, but there is no such figure for vegetarians eating the ‘alternative’ short chain sources of Omega 3s.

Question: Aren’t the seas overfished already ?

Answer: 70% of the world’s fish stocks are now fully fished, over fished or depleted so it would be remiss to encourage intake of fish without considering this issue. The key is clearly to eat fish, sustainably caught or farmed in a way that minimises environmental damage. The Marine Stewardship Council (MSC) endorses such products by use of a blue ‘tick’ logo which we should all be looking out for. More information can be found on their website (www.msc.org). Using ‘alternative’ short chain Omega 3 sources also helps sustainability issues.

How do I increase my fish intake without exposing myself to contaminants ?

Answer: There are concerns about levels of dioxins and mercury in oily fish which find their way into the food chain through rainwater or dumping of waste. The levels concentrate in bigger fish higher up the food chain, hence the specific Food Standard Agency guidelines for the intake of shark, marlin, swordfish, and tuna (see FSA website www.eatwell.gov.uk for specific advice). However for other oily fish it is widely accepted that the nutritional benefits far outweigh the disadvantages, and since intake is so low anyway, contamination is rarely considered to be an issue.

Question: What about supplements ?

Answer: Supplements are a well-documented route to increasing Omega 3 intake, but can be expensive, unpalatable and unsuitable for vegetarians. However there remains a growing market for supplements and they can have an important role for those requiring very high doses for therapeutic reasons eg. Severe rheumatoid arthritis sufferers, and for those who fail to meet their Omega 3 intake from other sources. Ensure that any supplements that you buy will usefully contribute to your intake and are manufactured from sustainable sources. Avoid using cod liver supplements since contaminants concentrate in the fish liver, and bear in mind excess intake of other vitamins eg Vitamin A , that may be included in the omega 3 capsules. These can be toxic if taken in large quantities and also needs to be considered if you are taking multivitamin pills.