Reporter: Sophie Hull

We've always thought that what this nation eats is the envy of the world. And in many ways it is. Which can't explain why so many of our children have a diet that is often damaging. Eating foods containing ingredients banned or limited by other countries. One family has managed to reverse this science experiment gone wrong. Today Tonight reports on how they've fixed asthma.

"Australia actually has the highest use of sulphites in food of anywhere in the world," said Katy Reed - director of Smart Snacks

Grace Jenkins is living proof of just how dangerous preservatives are to children. We've heard all the warnings from the experts but this little girl shows without question what sulphites are doing. For thousands of Australian children - it's the difference between sickness and health. Just one dried apricot. A sausage. A couple of slices of ham.

"The cumulative affect of putting preservative over the day in their diet is huge," said Katy.

Katy Reed - director of Smart Snacks, says Aussie kids are suffering in ways it's impossible to quantify; simply from eating food children from no other nation would be asked to swallow.

" Australian kids are eating way too many additives and preservatives now in their diets - they're actually having about three times the accepted amount of preservatives a day than the world health organisation says is the acceptable daily intake," she said.

"The easiest one to spot is my second child - she just turns into a feral animal she just says no to everything.The older one just gets moody and starts crying then she'll have problems with toileting issuesMy little boy we thought he was autistic - he was banging his head into walls and things," said mum, Jen.

Jen Bertold is one mum who found out the hard way - her children couldn't tolerate the cocktail of chemicals added to their food. It was even suggested her eldest daughter should take ritalin - the drug prescribed for Attention deficit hyperactivity disorder. But by removing additives and preservatives from Ashlin, Nuala and Gus's food - no drugs were needed.

"I know if they go away and stay the night with family or friends or have been to a birthday party and eat a lot of things that are not on our restricted diet it's hell for about a week afterwards. Every time it just refreshes our memory of how bad things could be," said Jen.

The incidence of asthma increases by five times when children return to school after the Summer break. There's mounting evidence to indicate this is because of the amount of sulphites packed into lunch box food. Juice drinks, processed meat, dried fruit. A single dried apricot can contain sixteen miligrams of preservative - more than a six year old child should consume in a day.

"The pediatrician told us that her asthma was unpredictable and that there probably was a trigger but that we would never find it," said Sarah.

Sarah Jenkins took the doctor's advice and put daughter Grace - now six - on a ventolin inhaler morning and night from just four months old. Grace's condition didn't improve with age so Sarah began investigating the possibility something more than medication could help.

"I have spent countless hours trawling through pages on the internet - I've read almost a hundred books on the topic now," she said.

What Sarah found astounded her: Grace's food - right from baby formula - was responsible for the coughing and restricted breathing. A diet free from Sulphites - that is any of the preservatives numbered 220 to 228 - meant a child free from asthma symptoms.

"I was horrified to find out that we'd been giving her preventers all her life and there was a good reason that we didn't have to," she said.

"Children who have additive and preservative free diets are children that are happier and healthier they've got better concentration better learning ability and they're just healthier all round," said Katy.

The United States has banned the use of sulphites in processed meats. In the UK a parliamentary committee has recommended artificial colours are banned in food. In Australia? Still no acknowledgement of the connection between additives and kids behaviour - despite the growing evidence.

"You see parents saying oh they're just wild and out of control but my kid doesn't have any problems with food. I just feel like laughing at them because it's so obvious what they're giving them has to have some impact," said Jen.

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