Omega 3 fats
Omega 3 is the name for a family of unsaturated fats that are essential for our health. The main Omega 3 fats are:
ALA (alpha linolenic acid)
This is considered the parent of all omega 3’s. It cannot be made in the body so it is essential to eat foods that contain it. It is mainly found in vegetable oils, nuts and seeds.
EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid)
These omega 3 fats are needed for a healthy heart and circulation. We can make some of our own EPA and DHA from ALA, but we are not very good at it. So it is helpful to get some from the food we eat. All fish and shellfish contain EPA and DHA; but oily fish, like sardines, salmon and mackerel, are considered to be the best source.
Are we getting enough?
Although our bodies can make EPA and DHA from ALA this process is very slow and only small amounts can be made. The easiest way to ensure you get enough is to eat fish. Current advice is to have two good portions of fish per week with at least one of these being oily. A portion means a serving of 140g; but this could be made up of 2-3 smaller portions across the week.
What are the benefits of a diet rich in omega 3?
Populations that eat more oily fish, such as those that live in the Mediterranean, Greenland or Japan, have been shown to have a lower risk of heart disease than the UK where we eat very little oily fish. EPA and DHA have also been shown to have anti-thrombotic, anti-inflammatory, and anti-arrhythmic benefits. This means they help to protect the heart and blood vessels from disease. Higher levels of EPA and DHA in the blood have also been linked with lower death rates from cardiovascular disease.
Eating oily fish is not only a good way to ensure your omega 3 intake – it’s also a good source of vitamins A and D, calcium, iodine and selenium, nutrients that are often lacking in our diets.
Which oily fish to choose?
The following are good sources of EPA and DHA. You can choose from fresh, canned or frozen fish.
- Herring (Kippers)
What if I don’t like fish?
Try to maximise the number of non-fish sources of omega 3 that you eat. Some foods have omega 3’s added to them, but often the amounts they contain are small.
Plant based sources of omega 3 (AHA)
- Oils especially flax, walnuts, krill and algal oils
- Nuts especially walnut, pecan, hazelnut
- Seeds especially pumpkin, chia, hemp
Food sometimes fortified with omega 3
Check the label for the amount and kind of omega 3. Foods are often fortified with AHA rather than EPA or DHA.
What about supplements?
It is always best to get your omega 3’s from foods. If you choose to top up on EPA and DHA from supplements you need to follow a few golden rules:
- Opt for a fish oil or an omega 3 supplement not a fish liver oil
- Choose a supplement with lower levels of vitamin A - less than 1mg (1000ug or 1000mcg) per day
- If pregnant or breastfeeding avoid supplements that contain vitamin A (as retinol) altogether
- Aim for an intake of EPA & DHA of 500mg each day
Are there any safety concerns?
Some fish contain small amounts of chemicals that may be harmful if eaten in large amounts. But overall the health benefits of oily fish far outweigh any risks. We can all safely eat up to two portions of oily fish per week and men more. But some people should avoid shark, marlin and swordfish altogether. Here is the recommended advice:
• Shark, marlin and swordfish – may contain small amounts of mercury – they should be avoided by women who are pregnant or planning a baby and by all children under 16. Other groups should eat no more than one portion of these fish each week.
• Women who are pregnant or breastfeeding and any women or girls who are likely to become pregnant in the future can safely eat up to two portions of oily fish per week
• Men, boys and women passed child bearing age (or not intending to become pregnant) can safely have up to four portions of oily fish per week