What's in our food: Eat, drink ... and be worried

* In this fourth part of a week-long series on food, Herald science and health reporters research the truth about the food groups we rely on.

From fruit, vegetables, meat and dairy products, to a look at grains and cereals today and followed by takeaways tomorrow, we ask what is good for you these days.

Take a typical "healthy" breakfast - a thick slice of fresh home-baked bread, lightly toasted and spread with butter and honey.

It looks good for you, at first glance. But what about all that butter? Will it give you a heart attack? And the honey. Won't it rot your teeth?

Well, the toast is half wholemeal flour, so at least it is good for you.

Not so fast. Some safe food campaigners have bread high on a "dirty dozen" list of foods containing pesticide residues and urge seeking out organic alternatives.

Lucky it's not morning tea time so you don't have to worry about synthetic dyes in your biscuits.

Meal times may never be the same if you do a risk-benefit analysis of the good and the bad in everything you eat and drink - the kind of check that has become more feasible with food labelling rules introduced in 2002.

The debate on pesticides food additives is between those - the scientific establishment - who say they are safe for most and those who say they can threaten good health.

The establishment view adds that addressing health risks like eating too much fat, sugar and salt is more important than worrying about additives.

Cereals - bread, rice, pasta and breakfast cereals - are one of the four main food groups.

Nutrition experts say we need to eat more of them, concentrating on whole-grain varieties rather than more highly refined white bread.

The Nutrition Taskforce recommended eating six servings of breads and cereals a day (one slice of bread is a serving), a level achieved by only one-fifth of the population.

Foods containing cereals are, like most of the food most of us eat, highly processed.

Fruits and vegetables commonly have pesticide residues, and manufactured foods draw from a bewildering array of several thousand colourings, preservatives, flavourings and other additives.

A British study of 277 pre-schoolers last year linked additives to hyperactivity after some of the children were given fruit juice containing additives and the rest given juice without them.

Despite the tiny amounts of pesticide residues and additives in food - levels deemed safe for most by Government authorities - campaigners such as Alison White and Jacky Pearson from the Safe Food Campaign say they could be harmful, particularly over the long term and especially for children.

A book they produced with Green MP Sue Kedgley as lead author, Eating Safely in a Toxic World, says that in 1978, Norway's Government banned synthetic "azo" dyes from foods after it was found that up to 1 per cent of Norwegians could have allergic reactions to them.

But the country's Food Safety Authority told the Herald that the ban was revoked in 2001 to bring Norway into line with the European Union.

Azo dyes are among synthetic dyes derived from coal tar, some of which are also used as pesticides.

Tartrazine, a yellow azo dye, is often listed on packaged-food labels as colouring 102 or E102.

The Eating Safely book and anti-additive websites say it is linked to asthma, hyperactivity in sensitive people and other health problems.

It is used in many foods including biscuits, snack food, sweets, jam and soup.

"We don't have a recent safety assessment on tartrazine," said Dr Peter Abbott, the Canberra-based principal toxicologist of Food Standards Australia New Zealand, which advises t food safety ministers in both countries on food additives rules.

"Tartrazine has been used in foods for generations, well before this authority was established. Its permission is historical in that sense.

"We keep an eye on any new studies that may come out on food additives, but we don't have comprehensive reviews of every old additive that's being used.

"Claims of possible long term effects are unfounded, certainly for new food additives."

It was unclear whether tartrazine caused the reactions blamed on it, and for most it held no safety concerns. Those who wished to avoid it could check the ingredients list.

In Britain, surveys by local authorities have found many takeaway curry cooks using excessive tartrazine and other colours to brighten their dishes.

Another colouring, erythrosine (127), was severely restricted in the 1990s after it was linked to thyroid cancer in rats.

A red dye, it was used in many foods including ice-cream wafers and cheerio skins. It is now limited to glace cherries, commonly found in Christmas cakes.

Abbott said there was no obvious replacement for it in glace cherries.

"It was permitted on the understanding that the levels of intake would be quite low and very unlikely to be a safety issue. You don't eat many glace cherries."

Jacky Pearson said the use of additives might have declined because of bad publicity about them, but erythrosine had simply been replaced by ponceau 4R (124), another azo dye.

Alison White said regulatory authorities tended to restrict additives only was there was absolute evidence, rather than taking a precautionary approach.

"They like to see the dead bodies lined up before they do anything."

The Herald asked White, who holds a public health diploma and is studying for a master's degree, and Professor Jim Mann, of Otago University's human nutrition department, to rate four common supermarket items.

They are a Tip Top medium sliced white bread, Sanitarium's Muesli Fruity Delight, Fanta soft drink, and Griffin's Hundreds and Thousands biscuits.

The bread

White said more than 90 per cent of bread samples in Government-commissioned Total Diet Surveys done by Environmental Science and Research (ESR) contained residues of pesticides such as chlorpyriphos-methyl, an organophosphate. It was used with other chemicals in grain storage, so pizza bases, biscuits, fish batter and any other foods containing flour, especially wheat, could contain residues.

Organophosphates could harm the nervous system and children were at greater risk because they ate more than adults in comparison to their bodyweight.

ESR found in the late 1990s that four of eight white bread samples contained chlopyriphos-methyl, but the figures suggest that a person would need to eat about 40 loaves a day for a lifetime to reach the acceptable daily intake, the level at or below which authorities expect no appreciable risk of adverse health effects.

Acceptable daily intakes - or ADIs - are a controversial measurement.

Some say they involve too much guess work, are set too high and obscure the potential combined effects of multiple residues.

But New Zealand's Food Safety Authority says there is no evidence for "this 'cocktail effect' myth".

ESR said the adult population's dietary exposure to chlorpyriphos-methyl was up to 1.8 per cent of the ADI, and up to 2.8 per cent for children - low, but up on its 1990-91 survey.

Mann focussed on the bread's nutritional value.

"This is a relatively low-fibre bread which would have a GI [glycaemic index, a ranking of carbohydrates based on their immediate effect on blood sugar] of about 100, so it would be quickly absorbed and rather comparable to glucose.

"I wouldn't be recommending it.

"There's some evidence high GI foods are not only are bad for people with diabetes, but seem to predispose to the development of diabetes. Low GI, high fibre is protective food against diabetes and tends to be more filling."

The muesli

Both our commentators worried about the vegetable oil - one because the product's box does not say if it is free of genetically modified material, the other because the the packet does not disclose if the oil contains trans fatty acids.

These fats can have an even worse effect on cholesterol levels than saturated fats.

They also wanted to know more about the muesli's whole grains.

Under the Food Standards Code, trans fats must be disclosed on packaged food only if the manufacturer makes a nutritional claim about fats or cholesterol.

Sanitarium said the muesli contained no trans fats and the firm had a "non-genetically-modified ingredient policy".

More than three-quarters of the cereal in the muesli was whole grain.

Mann said the product's whole grains, dried fruits and sunflower seeds were nutritious, but it was relatively high in sugar.

"If you're watching your calories it's not great."

White also welcomed the whole grains and fruits, but warned on pesticide

residues. She cited the presence of additives linked to asthma attacks, headaches, and rashes in sensitive people, and an undisclosed flavour.

"'Flavours' are the bane of consumers who want to be informed.

Manufacturers don't have to say what they are. The word 'flavour' covers all sorts of unknown things and sensitive people could react to some flavours."

The muesli contains the natural colour annatto (160b), the artificial dye allura red AC (129) and the preservative, used in many foods and wines, sulphur dioxide (220).

"It's to be avoided because of the allura and the sulphur dioxide," White said.

The biscuits

Mann: "This is a product with nothing much to commend itself, other than a lot of calories - bad calories."

"They are clearly a high fat high sugar product, relatively speaking."

"More than half the carbohydrate is sugar, and a lot more than half the fat is saturated fat."

He suspected the declared vegetable fat was high in trans fats, but the label, since it is not required to, does not say.

Griffin's told the Herald the trans fat level was "very small" - less than 0.3g for each 100g of biscuits.

White was concerned about the amount of salt and the colourings tartrazine, sunset yellow (110), ponceau and annatto.

Three were in the hundreds and thousands sprinkle topping so probably small in volume, but there were alternatives available to manufacturers.

Fanta

Mann: "It has no positive value whatever. It's purely sugar and water and some various flavourings and preservatives".

White: "It's a 'non-food'. Every time you have it you rob your body of nutrients."

In the New Zealand Medical Journal last year, Auckland University health researcher Professor Rod Jackson and two medical students suggested - as an anti-obesity measure - replacing the sugar in soft-drinks with artificial sweeteners such as aspartame, widely used in foods and diet drinks and sold under brands, including Nutrasweet.

Aspartame was safe for human consumption, they said.

But aspartame is the subject of huge controversy, and numerous web pages are dedicated to defending or demonising it.

Some critics link it to headaches, blurred vision and diabetes.

A 1996 study linked it to brain tumours, but the report's quality was questioned by a British panel which decided it raised no concerns about using the sweetener.
As with all food additive issues, it is up to the consumer to find the truth - or just to eat and hope that governments and big business can be trusted.