An open and shut case?

nutrition tableA must-read article. 

UK - After 50 years of conflicting evidence and advice, the fats in our food have been tried and sentenced. But have the real killers been identified — or are they still wrecking lives? Investigation by Richard Girling.

Food scares. Don’t they bring you out in sores? Proselytising zealots on the one hand try to tell us that “natural” is best, and on the other hand that, well, it’s only best if you skim off the fatty bits that actually make it taste of something. The penalty for noncompliance with dietary high command used to be rickets. Now it’s bad skin, obesity, heart disease, Alzheimer’s, depression, diabetes and cancer.

It’s a peculiarly human thing. Birds and animals know instinctively what is good and bad to eat, which is all to do with how food looks, smells and tastes. Humans, by contrast, have been taught to sublimate their instincts and eat what they’re told. The result is a confused populace that seldom understands the terms in which it is being addressed, but picks up the mantras of “good” and “bad” fat, high-fibre, five-portions-a-day and chuck-away-the-frying-pan. It swallows either the most recent prescriptions of the diet lobby or what is urged upon it by the wilier practitioners of the advertising industry. Sometimes – for nothing sells better than the promise of good health – the messages coincide. “Low-fat” foods are a good example. So are the plastic tubs of primrose-coloured grease that are slid across the table in some households when you ask for butter.

In the 1970s, specially selected stupid people were challenged in television commercials to “tell Stork from butter”, and we were asked to believe that 7 out of 10 couldn’t do it. Aside from arguments about how such a result could have been achieved (did they poll only smokers with a Capstan Full Strength on the go?), the hottest controversy then was whether the G in margarine should be hard or soft. Nobody doubted the twin prongs of the advertisers’ message – that the stuff spread straight from the fridge (demonstrably true) and that it was better for you than hard, saturated fats churned from cows’ milk (taken on trust). The eventual brand leader, Flora, built its whole image on the health benefits of eating hydrogenated vegetable oils in place of butter – a marketing slant that was bang in line with government health policy.

Nobody imagined that one day these very same oils would find themselves in the dock alongside the fat old lags they were designed to replace. But there they stand: accused, convicted and condemned. Hydrogenated vegetable oils contain trans fats, or “trans-fatty acids”, which it turns out are even worse for our hearts than the saturated fats we were taught to abhor. The current, highly publicised unrest in New York, where the health department wants to ban trans fats from restaurants and takeaways, is the latest flare-up in a war that has been rumbling for years. As in so many food scares, however, the truth struggles to live up to the headlines.

As in many food scares, too, mention of life-threatening disease has stimulated something very close to panic. In the UK this summer, a new rash of headlines was provoked, first, by some long-term American research showing that monkeys fed on polyunsaturates put on 30% more belly fat than those given monounsaturates; and then by the British Medical Journal, which argued in an editorial that – in the UK as in America – trans fats should be compulsorily labelled, just like the old-school killers saturated fats. It was all a bit late, though. Hydrogenated vegetable oils have been purged from spreads, and retailers and manufacturers (see panel on page 25) are racing each other to remove them from the plethora of other products – cakes and biscuits, pies and pastries, sweets, ready meals, chocolate, even Horlicks – in which they have been ubiquitous.

The old-school killers themselves, meanwhile, are rampaging around the supermarket as if they own the place. Buyers of processed meat products may not be the most discriminating consumers, but some will have wised up to the fact that the “meat” in their dinner, if laid out in its raw state, would not look appetising. The truth is, it would test the appetite of a hyena. To keep the lawyers happy, manufacturers have to satisfy the official “European definition of meat” introduced in 2003, which, you won’t be surprised to learn, differs in several respects from any definition your grandmother might have recognised. This has been tightened up somewhat (it now excludes, for example, brains, feet, intestines, lungs, oesophagus, rectum, spinal cord, spleen, stomach, testicles and udder), but there’s plenty of slithery stuff still going on, and half the “meat” could be fat, rind and gristle.

The trans-fat story began with that old-fashioned word “margarine”, and it’s a longer story than many people think. The word itself comes from the Greek margarites, meaning pearl – an oddly poetic image coined by its inventor, the 19th-century French chemist Hippolyte Mège-Mouriès. His recipe, processed suet mixed with buttermilk and water, patented in 1869, was inspired by the need for a cheaper rather than healthier alternative to butter. Moneyed folk continued to prefer milk fat, and the comparison with butter has obsessed margarine-makers ever since. Mège-Mouriès sold out to a Dutch company in 1871, and by 1889 factories were turning out margarine in Germany, Austria, America, Norway, Sweden, Denmark and England. By 1906 the supply of suet was being outstripped by the demand, and factories began to look instead to vegetable oils – a switch that was all but complete by 1920.

Margarine’s inferiority complex found some relief in the 1960s when it first realised the power of the health card. In that decade too, the original hard margarines, packeted like the butter they so desperately wanted to imitate, were replaced by soft varieties in tubs. The first margarine “high in polyunsaturates, low in saturated fats” hit the shelves in 1964. Twenty years later, the Committee on Medical Aspects of Food and Nutrition Policy (Coma) published its report Diet and Cardiovascular Disease, which once and for all spelt out the heart-stopping dangers of saturated fats. City streets began to vibrate with wobble-bottomed joggers staggering home not to naughty butter but to smears of vegetable yuk. In a London restaurant, I watched a man hack the fat from his parma ham as if he was fighting for his life. Proper butchers went on selling proper meat, but supermarkets were packaging stuff that looked as if it had been cut from Victoria Beckham.

Yet even as one branch of the food industry was pulling the saturated fats out of our diet, another was shoving them in again. Sausages, burgers, pies and pasties were being bulked out with body fat and other bits and pieces discarded by the butchers. Remember mechanically recovered meat (MRM)? The official definition quoted in the report of the BSE inquiry was unflinching: “Residual material, off bones, obtained by machines operating on pressure principles in such manner that the cellular structure of the material is broken down sufficiently for it to flow as purée from the bone.” As far as the law went, it was perfectly okay for these intimate scrapings, with their cellular structure broken down into gloop, to be described on packaging as “meat”. It was this very stuff, gleaned from places other recipes could not reach, that built the bridge between BSE and its nightmare human twin, Creutzfeldt-Jakob disease. Don’t imagine it has been banned, however. Manufacturers are simply not allowed to describe it in the labelling as “meat”. It will appear instead as “recovered pork”, or whatever.

There is another irony too. Cookery writers like to applaud the peasant cuisines of continental Europe and marvel at their thrift. It has been repeated so often that it has become a cliché: they use every part of a pig except its squeak. But the same middle-class writers clutched their throats when the principle was seized upon by pie-makers. If Britain had any living equivalent of peasant cuisine, it was – still is – ingredients of rock-bottom cheapness chemically enhanced to give flavour, shelf life and “mouth-feel”, then fashioned into the resemblance of food that needs little chewing but can only be swallowed with ketchup.

While all this was going on, the health-obsessed middle classes were piling on the polyunsaturates, even if they didn’t quite understand what they were – food science is as opaque as lard, and twice as slippery. Most people know at least that, like butter, hard margarine and cheese, lard itself is a “saturated” fat, hard at room temperature. This is the stuff that raises cholesterol, blocks our arteries and – by some accounts – hastens the onset of Alzheimer’s disease. Pretty much every health authority on the planet urges us to go easy on it.

Many people also understand “unsaturated” fats stay runny at room temperature and subdivide into polyunsaturates and monounsaturates. Polyunsaturates are said to protect against heart disease and arthritis, and are found in oily fish, soft margarines and some cooking oils (safflower, grapeseed, sunflower and corn oils, for example). Monounsaturates are said to be more or less health-neutral, though there is a suggestion they may reduce the risk of heart disease. They are found in olives, olive oil, nut oils and avocados. After that it all gets a bit hazy.

Even mainstream health advice wriggles with weasels such as “some experts now believe that”, which invites you to conclude that other experts think differently, and raises the question: how expert are the experts? Margarine, or “synthetic edible fat” as the Butter Board would prefer us to call it, remains the benchmark of dietary false idols. Unlike butter, it was not something you could make at home. Liquid vegetable oils were stiffened to a butter-like consistency (in other words, had their melting point raised) by a high-tech industrial process that involved extreme heat, metallic catalysts (nickel, for example) and hydrogen. A bit of fiddling with flavouring and colouring agents, stabilisers and salt turned these “hydrogenated vegetable oils”, now “high in polyunsaturates”, into margarine.

It was not long before scientists started adding some rationalist caveats to the good-health gospel. As early as 1974, Australian researchers found a link between polyunsaturates and skin cancer. In 1975 a group from the University of Glamorgan began to suspect that hydrogenated vegetable oils were implicated in coronary heart disease. Others around the world found links with cancers of the colon and breast. There was a particular kerfuffle in 1989 when the clinical pharmacology department at Cambridge University backed the earlier findings on heart disease. When The Sunday Times reported this, it drew an angry letter from the president of the Margarine and Shortening Manufacturers’ Association (who was also chairman of Van den Berghs, the manufacturers of Flora), complaining that the issues “had not been substantiated”. Van den Berghs itself followed up with full-page newspaper advertisements headed “Polyunsaturates Are Essential for Health”.

And so it went on. In 1991 the American Journal of Clinical Nutrition announced that “polyunsaturated vegetable oils promote cancer more effectively than do saturated fats or polyunsaturated fish oils”. In 2001, researchers at the Royal Children’s Hospital in Melbourne reported that a heavy intake of polyunsaturates could more than double a child’s risk of asthma. In 2002 a link with depression was suggested, and Walter Willett, head of Harvard University’s department of nutrition, famously added his weight to the opinion that low-fat diets were making people obese. In 2004 a researcher at the Medical University of South Carolina reported a possible link with Alzheimer’s disease.

But medical opinion is like a merry-go-round with the merriment removed. Assertion meets counter-assertion; rival camps ridicule each other’s methods and conclusions; each headline contradicts another. For consumers who can’t tell a linoleate from an eicosanoid from a bowl of custard, the result is like a babble of tongues in a science bazaar. We must assume, however, that the Food Standards Agency (FSA), the UK’s highest authority on such things, listens and understands. Its advice remains unaltered: polyunsaturates are good for us, and we should eat more of them. On the basis of reviews of evidence by the World Cancer Research Fund in 1997 and the British Nutrition Foundation in 1995, it rejects the idea that either polyunsaturates or trans fats are carcinogenic. Which, if we are looking for something to worry about, leaves just coronary heart disease.

By the early 1990s it was clear that the apparent risk in polyunsaturates came from the trans fats that were produced as a by-product of the hydrogenation process. In 1994, Flora quietly reduced the level of trans fats in its formulation from around 7% to 1.5%, and “margarine” slid towards obsolescence. Surprising to some, the word has a legal definition – it may be applied only to products with a fat content of between 80-90%. Any lower and it’s not margarine at all, but reduced-fat or low-fat spread bulked out with water (which is why it’s not good to cook with). According to the UK Margarine and Spreads Association (MSA), all non-dairy spreads are now less than 80% fat, so “margarine” is technically obsolete. By further chemical jiggery-pokery, says the MSA, the spreads mostly have a trans-acid content of less than 1%.

As things stand, however, unless you home-make everything and never eat out, you’ll have about as much chance of avoiding trans fats as you do of avoiding Christmas.

The first problem is knowing where they are – trans fats do not have to be listed on food labels. But, says the FSA, hydrogenated vegetable oils do have to be declared, which means that “if the ingredients list includes hydrogenated vegetable oil, there may also be trans fats in the product”.

Or there may not. Who knows? The difficulty arises because, truly speaking, it is only partially hydrogenated vegetable oils – the semi-soft ones – that contain trans fats. Fully hydrogenated ones do not. Yet the labelling regulations make no distinction. Partially or fully hydrogenated, it’s all the same: the label will list only “hydrogenated vegetable oil”. And the muddle continues. As the FSA puts it, “Trans fats count as part of the total fat in the nutritional information on the label. They are not classed as saturates, monounsaturates or polyunsaturates, so they won’t be included in the figures for these.”

So, the only certain way to be sure your food contains no added trans fats is to buy organic. The FSA says it will seek an “appropriate amendment” when the EU nutrition-labelling directive is revised next year, but in the meantime it is being left to food companies to clean up their recipes.

This is actually less of an evasion than it sounds. Though the headlines have elevated trans fats into the most determined killers of humankind since the plague rat, the fact is that most of us eat very little of them. In common with the World Health Organization, the FSA warns that no more than 2% of our daily energy intake should come from trans fats. The most recent National Diet and Nutrition Survey (NDNS) of adults, in 2000-1, showed a national average of just 1.2%. And neither did this look like a statistical artefact with a low average disguising high peaks. The same survey showed that 97% of adults were consuming within the safety zone. An earlier NDNS of young people aged 4-18, carried out in 1997, showed that 96% of even this temptation-prone group were staying within limits. Since then the herd impulse of the packaged-food industry has seen them stamp on trans fats with the exterminating zeal of cockroach-hunters, so that popular brands now commonly contain no more than the trace amounts found in raw ingredients. The latest estimate for trans fats is down to 1.1% of total daily energy intake. Hence the FSA’s apparent insouciance.

 

But we don’t live by packaged food alone. Logically, the labelling regulations apply only to foods that are labelled. Food sold loose is not affected; neither are cooked meals, so the bakery and catering trades are not inconvenienced. Pubs, schools, canteens, hospitals, fast-food joints, cafes, restaurants, takeaways, chocolate shops, confectioners, bakers – all these are free to go on enjoying trans fats’ triumvirate of holy virtues – cheapness, convenience and extended shelf life – and to grease our arteries with whatever they please. For fast-food addicts in particular, the numbers do not stack up well. Rule of thumb: a 5g-a-day trans-fat habit raises the risk of heart attack by 25%. A worldwide survey published in The New England Journal of Medicine earlier this year showed that you can get more than twice that amount (in the worst cases more than four times) in a single visit to McDonald’s or KFC (Kentucky Fried Chicken). Hence the furore in New York. America, of course, is a different country. Its diet is so fat-laden it’s like liposuction in reverse: the average intake is a theoretically unsurvivable 6g of trans fats daily. At the same time it has a blame culture so finely triggered that it hardly lets a sneeze go by without pursuing the culprit. Lawyers can no more pass up a food-related illness than their clients can turn down a Big Mac with double fries.

 
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McDonald’s, Kraft and KFC have all felt the hot breath of the law on their necks, and since January the Food and Drug Administration (FDA) has required trans fats to be listed on all US food labels. In September the New York health department went further, proposing that artificial trans fats should be banned from every one of the city’s 22,000 restaurants. After a period of public consultation, a final vote next month is expected to result in restaurants being given just six months to make the switch to oils, margarines and shortenings containing less than half a gram of trans fats per serving.

It leaves open the question of what would replace them (butter? Lard? Dripping? Goose fat?) – but Walter Willett received the news with rejoicing. “If New Yorkers replace all sources of artificial trans fat,” he said, “by even the most conservative estimates at least 500 deaths from heart disease will be prevented each year – more than the number of people killed annually in motor vehicle crashes.” It was enough to push even KFC into announcing a trans-fat ban in its 5,500 US restaurants, though it gave no such undertaking for its 711 outlets in the UK.

So why no pressure in Britain to follow the  American example? The FSA explains that “some fast food chains” are switching to non-hydrogenated cooking oils, but seems chary of interfering in case restaurants are driven back on to saturated fats – which would make the situation worse rather than better.

Ironically, the chief beneficiaries of the trans-fat fuss have been the unreconstructed, old-style fat barons who enjoy nothing better than to divert our attention from the nature and content of “meat”. Butchers’ leavings continue to be scraped up, homogenised and stuffed into pastry.

The law has rather more to say about “meat”, however, than it does about vegetable oils. Legislators have crawled through the carcasses of every animal that we might be tempted to eat, and ruled on the palatability of every blob and nodule they’ve met en route. There has been some fiddling. In the old Meat Products and Spreadable Fish Products Regulations, meat was defined as “flesh including fat and skin, rind, gristle and sinew in amounts naturally associated with the flesh used”. A new European definition, introduced in 2003 via the Food Labelling (Amendment) Regulations, rewrote this to read “skeletal muscle with naturally included or adherent fat and connective tissue”, which sounds marginally less off-putting but means pretty much the same. The precise amounts of fat and connective tissue – that’s skin and rind, ligaments, tendons and cartilage (aka gristle) – vary according to species. If your specialism is anatomy, you might not be too surprised by how big the amounts “naturally included or adherent” actually are. If you are an ordinary shopper who visualises “meat” as rose-coloured lean stuff, then you might not have realised what the Quantitative Ingredient Declaration (Quid) on a meat product actually means. Pig parts, for example, can contain 30% fat and 25% connective tissue, and still pass for “pork”. For birds and rabbits the permitted limits are 15% fat and 10% connective tissue. With beef, lamb and mixed meats it’s 25% each.

This doesn’t mean extra fat and spare parts are banned from your burger or sausage – producers are free to add more, but the excess must be listed separately and cannot count as meat. No Quid is required, however, so you won’t know the quantity. The same goes for MRM.

The term “naturally included or adherent” is so misleading that it amounts almost to deceit. What it implies is that meat is brought to the kitchen whole, and used with the fat and other tissues “naturally” attached to it. But it means nothing of the sort. In practice, all this stuff – back fat, chicken skin and pork rind, for example – is stripped from “primal joints” as waste, then brought to the mixing bowl separately. The only nod towards “natural adherence” is the stipulation that all the flesh, fat and sweepings stirred into any named “meat” must be taken from the same species.

You might be forgiven for supposing, nevertheless, that all these bits and pieces would be recombined in more or less the same proportion in which they are found on the carcass. Wrong again. Lean pork with a small amount of visible fat – the kind most people would choose from a butcher – is 13.8% fat (against the 30% allowed by the regulations) and 7.8% connective tissue (against the 25%). Even untrimmed pork belly with the rind left on – one of the fattiest cuts you can buy – is only 23.8% fat. Lean stewing beef may contain as little as 6.2% fat (against 25% in the regulations), though it’s fair to say that some other cuts are much fattier (brisket, for example, can exceed 30%). Skinless chicken breast is just 2.1% fat (15% in the regulations).

Even with the skin left on, it’s only 6.7%, and the very fattest “natural” chicken joint – skin-on thigh, at 12.9% – is still leaner than the chicken “meat” that is recognised in manufactured products. What bumps it up is a tempting concoction known as “mixed chicken meat with skin”, weighing in at 23% fat.

Internal organs and other components – heart, tongue, liver, kidney and most head meat – on the other hand, don’t count as “meat” at all, and neither may they be labelled generically as “offal”. They must be listed separately by name, but do not require a Quid. Uncooked-meat products may not include the nasties – brains, lungs, rectum, spinal cord and the rest – a regulation for which we must be duly thankful.

But of course this leaves open the question of cooked meats, to which no such restriction applies. Post-BSE, bovine brains and spinal cord are still banned – otherwise the peasant principle pretty much applies, and the best you can say is that you’re helping to reduce waste. Neither do the limits on fat and connective tissue apply where the meat in a product is listed as “cooked” (fried chicken, roast pork, etc). The Quid will simply declare the weight of cooked meat added to the recipe, so you have no way of knowing its provenance.

The one concession to healthy eating is purely accidental – the Meat Products Regulations allow manufacturers to get away with so little “meat” in their recipes that you don’t actually have to eat very much of it. An ordinary burger need contain no more than 62% “beef”, and an economy burger no more than 47%. Meat pies and puddings pass muster at 12.5% “meat” content (or 10% if the pie is small), which is more than double the minimum (6%) for pasties and sausage rolls.

It’s hard not to be cynical. The food industry generally has been rivalled only by tobacco in putting profit before health. In May 2004 the World Health Organization issued new advice to food processors, retailers and caterers on how they should be helping the fight against obesity, heart disease, diabetes and cancer. Earlier this year London’s City University checked the world’s top 25 food companies to see how they had responded. Only 10 of the 25 were taking the recommended action on salt; five on sugar; four on fat and eight on trans fats. But at least the eight – that is, Cadbury Schweppes, ConAgra, Danone, Kraft, Nestlé, PepsiCo, Unilever and Ahold – were heavy hitters whose example might encourage the others.

But why the sudden change of heart when the dangers had been apparent for so long?

An awakening conscience is one (just) possible explanation. Negative publicity and legal pressure in America is another. But marketing is the most powerful driver of all. The new synthetic fats are just as cheap as the old ones, and there’s nothing to which the public responds more wholeheartedly than the news that yet another harmful ingredient has been stripped out of its dinner – albeit by the people who put it there in the first place.

So expect a blizzard of “zero trans fat” labels and lots more healthy-eating guff. (In February, in a bizarre reversal of Flora’s ad of 1989, Marks and Spencer took full-page advertisements in national newspapers announcing the removal of hydrogenated fats from all its ready meals.)

One wonders how much care will be taken to ensure that the no-trans-fats message is not taken by the more credulous kind of customer to mean no fats at all, and how long it will be before the new fats generate their own new health scares. As ever, there is no better advertisement for fresh, home-cooked food than a moment’s thought about the alternatives.

The producers

Though it plays down the risk of trans fats, the food industry is falling over itself to get them out of its products. M&S has already removed hydrogenated vegetable oils — a source of trans fats — from its own-brand foods. Sainsbury’s, Waitrose and Tesco will follow suit by the end of the year, and the Co-op by March 2007. Meanwhile, manufacturers say they are reformulating branded lines as fast as they can.

Cadbury Schweppes
Over the last nine months Cadbury has removed trans fats from all but three of its chocolate products — Double Decker, Boost and Time Out — which the company says its food chemists are currently “working on”.

GlaxoSmithKline
Horlicks currently contains small amounts of trans fats (approximately 0.38g per serving, or about 6% of the recommended daily intake). The company aims to remove these by September 2007.

Kellogg’s
The company's breakfast cereals contain no hydrogenated vegetable oils. Small amounts of trans fats remain in “a very small number” of its snack foods, but it aims to remove these by the end of the year.

Masterfoods
Says that by carefully controlling the oils and fats, it has reduced trans fats in its confectionery range — including Twix, Snickers, Celebrations, Galaxy, Mars, Bounty, Milky Way, M&Ms, Revels, Tracker, Starburst and Skittles — to less than 0.5% by weight.

Nestlé UK
The company has an “ongoing, active reformulation programme” to reduce and, “where feasible”, remove trans fats from all 66 of its retail product groups. It says that 55 of these — including popular brands such as Rolo, Toffee Crisp and Breakaway — now contain no added trans fats, and it has reduced trans fats in the remainder to less than 1% total energy, in line with World Health Organization guidelines.

RHM
Has already removed hydrogenated vegetable oils from Cadbury’s Mini Rolls and much of the Lyons and Mr Kipling cake ranges, and says that it will have reformulated the remainder by “early 2007”. RHM would not answer questions about its other brands — Sharwoods and Bisto — but said that trans fats in “most” of its products accounted for less than 1% by weight.

Unilever
Says added trans fats have been eliminated from all its UK product ranges, including Flora, Stork, I Can’t Believe It’s Not Butter, Hellmann’s, Knorr, Bertolli, Peperami, and Ben & Jerry’s, Magnum, Solero, Viennetta and Wall’s ice creams.

United Biscuits
Has removed partially hydrogenated vegetable oil from the entire McVitie’s, KP and Jacob’s ranges, and now bakes or fries all its snack foods, including Hula Hoops and McCoy’s crisps, in non-hydrogenated vegetable oils.

Weetabix
The company has never used hydrogenated oils or fats in any of its cereals or in its cereal bars.

Get your fats right

A survey commissioned by the Fat Panel in August this year revealed a startling degree of public ignorance and confusion. Even now, less than half the British population understand that saturated fats are bad for health, and 16% think trans fats are good. Nearly a quarter believe that essential fatty acids, such as omega-3, are bad, and 30% that monounsaturates are unhealthy. Even when people do understand which fats are heroes and which are villains, it’s of little practical use because
they don't know which foods contain which fats.

This should help:

Saturated fats
Solid at room temperature and mostly (but not all) of animal origin. Examples include butter, lard, dripping, suet, coconut and palm oil. They raise “bad” cholesterol levels and increase the risk of heart disease. Main dietary sources are full-fat dairy food, butter, meat and meat products, pastries, biscuits and cakes.
 
Monounsaturated fats
Liquid at room temperature, and sometimes known as omega-9, these are found in olive and rapeseed oils, meat, nuts and seeds. Dietary sources include meat and meat products, cereals, potato snacks and non-dairy spreads. They benefit health by suppressing “bad” and promoting “good” cholesterol.

Polyunsaturated fats
Occur in two “families’ — omega-6 and omega-3 — known as "essential fatty acids" because, although the body cannot make them, they are essential for normal physiological development. Omega-6 aids growth, reproduction, haemostasis (coagulation of the blood), the immune system and healthy skin. Dietary sources are vegetable oils such as sunflower, safflower, corn and soya (including spreads made from these), plus meat, nuts and seeds. Omega-3 aids vision, memory, learning and heart function. Dietary sources are oily fish (sardines, mackerel, herring, salmon) and spreads. A healthy diet should include four times more omega-3 than omega-6.

Trans-fatty acids
Also known as trans fats, these are by-products of the industrial process that creates partially hydrogenated vegetable oils. Although these have been eliminated from spreads and are being removed from many other branded foods (see panel on page 25), they remain ubiquitous in the bakery, fast-food and catering trades. They are reputedly even worse than saturated fats in terms of promoting heart disease.

Trans fats also occur naturally in dairy produce and the flesh of ruminants (beef, lamb), so trace amounts may remain in products even where hydrogenated oils have been removed.

Low-fat spreads
No branded spread now contains hydrogenated oils. Spreads are made instead by blending naturally liquid vegetable oils (sunflower, olive, rapeseed) with naturally solid ones (palm or coconut) to achieve a spreadable consistency, which is relatively low in saturates and high in polyunsaturates.

Information supplied by the Food and Drink Federation, Food Standards Agency and industry sources

source - Times Online