The Food Magazine - Click to return to the home page

Published in The Food Magazine 31st May 2010
Report by Anna Glayzer and Jessica Mitchell

The Food Magazine investigates omega-3 fatty acids in your diet

Most fats and oils are made up of a number of different types of fatty acids, and the properties of fats and oils, and their impact on health, comes from the combinations and amounts of different fatty acids they contain. Fatty acids can be either saturated or unsaturated, and within the unsaturated group are some fatty acids commonly called omega-3 fatty acids.

This group of fatty acids includes one of the essential fatty acids, Alpha-linolenic Acid (ALA) which cannot be synthesised in the body and Eicosapentaenoic Acid (EPA), and Docosahexaenoic Acid (DHA) which are present in some foods or which can be made in small amounts by the body. There remains debate over how efficiently humans make these fatty acids: it is likely that premature babies require additional sources of these fatty acids but the evidence for other population groups is not clear. EPA and DHA are found primarily in fish oils and are very long-chain fatty acids which allow liquids to stay fluid even at very low temperatures. These particular fatty acids have been suggested as being beneficial to adults in protecting against heart disease. 

Do omega-3 fatty acids really benefit heart health?  

The benefits of fish oils have been frequently debated. Dr Lee Hooper, Senior Lecturer in Research Synthesis and Nutrition, in the School of Medicine, Health Policy and Practice, at the University of East Anglia, has questioned whether oily fish and/or omega-3 fatty acid supplements improve health. At a recent presentation to a meeting of the National Heart Forum, Hooper said that, on the whole, scientific evidence appears to demonstrate beneficial effects of omega-3 fatty acids or fish consumption on total risk of mortality. However, these findings are complicated, as people who eat more omega-3 fatty acids or fish also seem to lead overall healthy lifestyles, eating a better diet and are less likely to smoke. 

Hooper told the meeting, “While we can find single studies that show important effects on health, the pooled evidence overall is not strong. Furthermore, fish and omega-3 supplements contain factors other than omega-3 fats such as selenium, iodine, calcium, vitamin D, protein, so, there may be health benefits of omega-3 fatty acids (or fish) in the general population – but it is not clear which these are or how important they are for health.” 

Because of studies linking consumption of oil rich fish to better heart health the Food Standards Agency advises people to eat at least one portion of oily fish per week. There is some confusion about omega-3 fatty acids, however, as foods which contain ALA such as some vegetable oils, seeds, dark green leafy vegetables and dairy products are often also suggested as being good for heart health, even though there is no evidence for ALA in this way.  

Not eating enough  

The amount of omega-3 fatty acids recommended has been determined by the government’s Scientific Advisory Committee on Nutrition which suggests eating a minimum of 450mg per day (3g per week) of long-chain omega-3 fatty acids. However, information from national dietary surveys shows that the national average is about 250mg/day. There will obviously be considerable variation in intakes, but it is likely that some population groups eat even less. For example, information from the Food Standards Agency’s (FSA) Low Income Diet and Nutrition Survey shows that adults in low-income groups have under 200mg/day of these fatty acids on average. 

The FSA suggests that one portion of oily fish (such as herring, mackerel, trout, salmon, fresh tuna, sardines) is about 140g, and this alone can provide the minimum 3g of long-chain omega-3 fatty acids that you need a week. However, FSA research also suggests that less than half of men and women consume oil rich fish regularly. 

To confuse the issue further, FSA advice also suggests maximum amounts of oil rich fish for some population groups because some pollutants, like dioxins and poly-chlorinated biphenyls, accumulate in oily fish. They can affect the development of a fetus, and so the FSA recommends a limit on the amount eaten from a young age. 

Maximum 2 portions
of oily fish per week
Maximum 4 portions
of oily fish per week
Girls and women who might have
a baby one day
Women who won’t have a baby
in the future
Women who are pregnant
or breastfeeding
Men and boys

It is also difficult to be certain just how much of omega-3 fatty acids there are in different oily fish – this will vary according to their diets, how they are produced (farmed or wild), the type of fish, if they are processed and the time of year. Mackerel, salmon, herring, sardines, trout and fresh tuna are the richest sources of long-chain omega-3. But, other oily fish and some shellfish are also sources including mussels, crab, squid, pilchards and eel. When tuna is canned it reduces the amount of omega-3 content – down to the level of white fish, so it does not count as an oily fish. 

Making claims on labels  

Recent months have seen the culmination of a European level reconsideration of rules around making claims over omega-3 content in foods and drinks. An amendment to the EC Regulation on Nutrition and Health Claims Made in Foods (legislation defining a single list of health claims that can be made on foods applying to all EC countries including the UK) was finally agreed in February 2010. The amendment (EC 116/2010) defined what levels or type of omega-3 content should be used to back packaging claims.  

For packaging to bear the claim ‘source of omega-3,’ products must contain

  • At least 300mg of ALA per 100g and per 100kcal
  • At least 40mg of EPA/DHA per 100g and per 100kcal

For packaging to bear the claim, ‘high in omega-3,’ or ‘rich in omega-3’ products must contain:

  • At least 600mg ALA per 100g and per 100kcal
  • At least 80mg EPA/DHA per 100g and per 100kcal

In March 2010, the European Food Safety Authority (EFSA) published dietary reference values for intakes of some nutrients. Dietary reference values (DRVs) represent benchmark intakes of energy and nutrients and should be used for guidance around maintaining a diet for good health. The level of a nutrient required to make “source of” claims is derived from a percentage of the DRV. So, the higher the DRV, the higher the level of the nutrient required for packaging to bear claims. For EPA/DHA, EFSA adopted the draft value of 250mg/day that it had previously proposed in June 2009 (The EFSA Journal (2009) 1176, 1-11), saying: “A daily intake of 250 mg of long-chain omega-3 fatty acids for adults may reduce the risk of heart disease.” ALA was not considered as beneficial as EPA/DHA, so EFSA stopped short of setting a DRV, stating instead: “ALA cannot be synthesised by the body, is required to maintain “metabolic integrity”, and is therefore considered to be an essential fatty acid.” An adequate intake level of 0.5 per cent of total dietary energy was proposed. 

The DRV of 250mg per day for EPA/DHA was significantly lower than the UK government recommendation of 450mg per day, and lower than scientists and the omega-3 supplement producers had lobbied for. The rulings also mean that despite there being no set DRV for ALA, claims can be made for products as being a “source of,” or “high in” omega-3, providing they contain at least 300mg of ALA per 100g and per 100kcal or 600mg respectively. Although the regulation says that the type of omega-3 should be stipulated, there is no requirement to do so front of pack. This is a potential source of confusion, argued a group of academics back in September 2009 when the rules were still in proposal form. John Stein, Professor of Neurophysiology at Oxford University said that: “manufacturers would be able pour in cheap plant oils, but imply that they deliver the same health benefits as fish oils. This exploits consumers’ faith in omega-3s”.  

The FSA is also at odds with the European legislation. In October 2009, whilst final EC discussions on the “source of” and “high in” claims were taking place, the FSA told an online food business news service: “We want any claims agreed at EU level to be supportive of Government dietary advice, and not mislead consumers into believing they can achieve their recommended dietary intakes of DPA/EHA from foods other than oily fish. Oily fish is the only significant dietary source of long-chain omega-3 fatty acids and consumers are recommended to eat two portions of fish per week of which one should be oily. Plant derived short-chain fatty acids (ALA) offer no significant cardiovascular benefit to consumers.” 

Now that EFSA has recommended a DRV for long-chain omega-3 of 250mg/d, the FSA continues to advise a higher intake. The FSA told us: “FSA advice remains unchanged: SACN recommend 2 portions of fish (one oily and one white) per week – this is equal to 450 mg/day of long-chain omega 3 fatty acids (EPA and DHA).” Similarly, the British Dietetic Association told us: “Current UK policy and guidance recommends that people aim for two portions of fish per week one of which should be oily – which would provide 450mg EPA/DHA per day.” 

FSA dietary nutrient guidelines
Recommended Daily Intake Age of person Amount
Omega-3 All 450mg per day
Salt Adult 6g per day (2.4g sodium)
Salt 7-10 years 5g per day (2g sodium)
Salt 4-6 years 3g per day (1.2g sodium)
Salt 1-3 years 2g per day (0.8g sodium)
Saturated fat Female Adult 20g maximum
Saturated fat Male Adult 30g maximum
Saturated fat 5-10 years 20g maximum
Sugar 5-10 years Less than 10% dietary energy or about ten teaspoons maximum per day (about 40g)
FSA calculation - Salt = sodium x 2.5 (from FSA website)

Product survey  

The Food Magazine did a product survey to see whether it was easy for consumers to distinguish between products containing long-chain EPA/DHA omega-3 from fish oils and shorter chain ALA from plant sources, or whether products bearing omega-3 claims do have the potential to mislead. We were also interested to see whether it would be possible to consume the recommended daily amount of long-chain omega-3 by eating these products, and what the nutritional impact of doing so would be. For the purpose of the survey we have used the UK recommendation of 450mg per day. We purchased 21 products from major food retailers. Products purchased included margarine, oil, ready meals and fish fingers. All 21 were purchased in the spring of 2010. All 21 products carried front of pack omega-3 claims.  

On reading the ingredients labels more closely, we found that:

  • 13 of the 21 products contained the more beneficial long-chain fatty acids (specifying EPA/DHA or stating from fish oil sources).
  • 7 specified that they contained ALA or omega-3 from plant sources
  • One product (Braham and Murray Good Oil), just said omega-3 (we assume this is ALA, a short-chain omega-3 fatty acid, as the product contains only hemp oil).

There is little to distinguish between the claims on the front of pack. For example, we bought three types of Flora margarine. The Flora Omega3plus pack said, “Rich in two types of Omega 3 to help keep your Heart Age young,” and “The spread with the most omega 3(EPA/DHA).” The Flora White pack said, “Helps keep your Heart Age young with Omega 3 and 6.” The Flora Buttery pack read, “rich, buttery taste with Omega 3 and 6.” Only the Flora Omega3plus pack contains long-chain omega-3 fatty acids, the other two contain short-chain omega-3 fatty acids from plant sources. It would take a well informed and sharp eyed consumer to spot the difference. In fact, out of the 8 products that contained omega-3s from plant sources, only one, the Linwoods milled organic flaxseed, sunflower and pumpkin seeds referred to the type of omega-3 on front of pack, in this case by saying OMEGA 3 (ALA). 

Of the products that contain long-chain omega-3 (EPA or DHA), you would have to eat an awful lot of many of them to consume the UK government recommended daily amount of 450mg/day. 

You’d need 8 fish fingers, or 6 tins of Heinz mini ravioli (costing you over £4.00), over 23 slices of Kingsmill 50/50, or more than four Young’s fish steaks in either butter or parsley sauce, (costing you about £4.00). Not only would this be expensive, when you consider that a 125g tin of mackerel (an oily fish) costs around 70p in most supermarkets and provides over 450mg of long-chain omega-3; it might also involve eating high levels of less beneficial nutrients. 

The Heinz products do not quite meet the new requirements for even the basic statement ‘with omega-3’ and will need to increase the amount of fish oil added to the products if they are to continue to bear such labelling. 

Fat, saturated fat, sugar and salt  

10 products are high in fat, saturated fat or both when judged against the Food Standards Agency traffic light labelling criteria. Of those, seven contain no long-chain omega-3 fatty acids at all. Yet, those long-chain omega-3 fatty acids are precisely the type that government dietary advice recommends we eat more of. All 5 margarines are high fat and saturated fat, and only two contain the more beneficial long-chain omega-3 fatty acids. The Hellmann’s mayonnaise (high fat, saturated fat, and at 1.5g per 100g of product, if it contained anymore salt at all, it would also be classed as high salt) contains no long-chain omega-3 fatty acids at all. All three oils are classed as high in fat and two are high in saturated fat. Yet, only 1, the Sainsbury’s Extra Virgin Olive Oil with omega-3, contains long-chain omega-3 fatty acids. The milled seeds are also high fat and saturated fat and contain no long-chain omega-3 fatty acids. 

However, it is not just these products that are a concern – if you tried to get your full daily amount of long-chain omega-3 from many products in our survey, you would be at risk of taking in too much fat, saturated fat, or salt – all nutrients the FSA says we need to eat less of. The European Heart Network (EHN), an alliance of charities working on cardiovascular health, would like to see the EC tighten up its labelling laws to ensure that high fat, saturated fat, salt or sugar (HFSS) products do not bear omega-3 claims, or indeed any type of health/nutrition claim, and that all products, including foods making omega-3 claims, have front-of-pack labelling that would make consumers aware of their HFSS content. 


Five of the products would put you on level, or over the maximum daily recommended adult salt intake of 6g if you tried to get your full daily allowance of long-chain omega-3s from them: Kingsmill 50/50 bread (9.48g); Heinz mini vegetable ravioli (7.8g); Heinz Spiderman pasta shapes with mini sausages (6g); Heinz mini pasta spirals in cheese sauce (7.5g); Heinz baked beanz with mini pork sausages (7.2g). 

Saturated fat 

You would need to eat 6 tins of the Heinz Spiderman pasta shapes with mini sausages to get the full recommended daily minimum of long-chain omega-3s. That would provide 17.4g of the saturated fat – only 2.6g under the maximum recommended intake per day for women and children. You would need to eat 4 pouches of the Young’s fish steaks in butter sauce to get your daily allowance of long-chain omega-3s – that would also give more than half of the daily recommended maximum saturated fat intake for women and children. If you chose Utterly Butterly to provide the full recommended daily amount of long-chain omega-3, you would also consume around 24g saturated fat- 4g over the maximum recommended amount for women and children. 


The FSA’s dietary advice is clear – aim for an average of around 450mg/day of long-chain omega-3’s from oily fish sources. The UK’s experts have not endorsed the lower European recommendation of 250mg/day. 

If you are aiming to get your omega-3 intake from processed food sources (including those made with fish not considered oily), and not from oily fish, it can be confusing to tell if you are really managing to meet dietary advice. And, you may be adding unhealthy amounts of salt, fat, or saturated fat to your diet. Our survey showed that even if consumers are aware of which type of omega-3 is most beneficial; often it is only by scrutinising ingredients labels on the back of packets that they can distinguish between products with long-chain and short-chain omega-3s. The Food Magazine survey only found three products that specified the type of omega-3 on front of pack. Almost half of the products would be awarded a red traffic light for either salt, saturated fat or fat, and if you tried to get your recommended daily amount of EPA/DHA from some of these products (should they actually contain EPA/DHA) you might have to consume unwelcome levels of fat, saturated fat or salt. Our advice? Stick to the oily fish if you can, preferably certified by the MSC as from a sustainable source. 

To see the results table from our survey and to read this article in full, please see issue 88 of The Food Magazine. Alternatively, if you are a current subscriber, you can download the full magazine as a pdf file from this website.