Monday, November 20, 2006

An open and shut case?

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 Britain's 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.


The organic delusion

The [British] Food Standards Agency, having examined the evidence, does not yet accept that organic food is any healthier than its non-organic equivalent. Meanwhile, its nationwide inquiry into food fraud, we learnt last week, has uncovered an industry riddled with sharp practice and Jesuitical labelling. Not only have we been taking it on trust that organic food is better for us; it turns out we've been taking it on trust that it's organic food at all. It can cost as much as five times the price of ordinary food and yet sales are rising by 12% every year. Why - do we all have money to burn?

I don't believe there is any rationale to it really. I think that when people buy organic it's a purely emotional thing: an all-purpose placebo to keep any number of middle-class anxieties at bay. Pay a little extra for those chemical-free vegetables and hey, maybe the children do watch too much television, maybe I needn't have used the car this morning . . . but dammit, these vegetables are so expensive they must be doing us good. At least I'm doing something right.

Look around. We have a population with a life expectancy verging towards treble figures. More or less. People - and not just the organic-eating classes - are growing faster, taller and stronger every year; our babies are born healthier; our children by and large are thriving. If we are what we eat then clearly we've been doing something right for some time - since long before this new organic explosion.

A woman I know recently invited her son's six-year-old friend over for supper. After accepting the invitation, the friend's mother proceeded to give a long list of the things the boy wouldn't eat - including pizzas, burgers and chips, so she was obviously lying. Then she said, with a slightly mad, hysterical giggle, "And of course, I mean, we all eat organic, don't we?" My friend's response was a lot more polite than mine would have been.

There is something vaguely disgusting about the modern obsession with healthy eating when so much of the world is starving. Whether or not organic food proves to be better in long run, I think - for the sake of good taste if for nothing else - that it's time we all learnt to be be a bit cooler. After all, we face a neverending stream of health warnings and health scares and we should have learnt by now that they never come to much. We have not been wiped out by BSE. We were not wiped out by Edwina Currie's salmonella and we won't be wiped out by this week's salmonella scare either. Avian flu scared the living daylights out of us but it never came to much. In any case the sad fact is, somehow or other, death will come even to the children of the middle classes. Even if they are fed organic.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter? It is just about pure fat. Surely it should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). For a summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and no lasting harm from them has ever been shown.


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