Is genetically modified food safe to eat?

Monday, May 14, 2007
It seems nowadays that when it comes to food there's a thousand issues — is it fresh or frozen? Organic or not? Will it make me fat?

Well there's one more issue just to confuse the situation. Is it genetically modified? Before the genetic revolution, food was as nature intended. Now scientists have created new supercrops, resistant to pests and disease.

So is genetically modified food safe to eat? Or are we just about to unleash nature's fury?

Dr Andrew Rochford finds out more.

Farmer Peter Corish is firmly pro-GM crops. He's been growing genetically modified cotton on his New South Wales farm for more than a decade.

"Eighty percent of the cotton we produce is genetically modified or bollgard cotton, which has been a huge advantage to the Australian cotton industry since its introduction about 11 years ago," he says.

The big benefit as far as Peter is concerned is the dramatic reduction in his use of chemicals. This cotton has been bred to contain its own inbuilt insecticide so needs very little spraying against pests. The plant's also resistant to commonly used weedkillers, like Roundup.

"What you're seeing here is weed plants, grasses that have actually been sprayed with Roundup and of course they're dying, yet the cotton plants are fine."

So chemicals kill the bad stuff — weeds — but leave the good stuff — cotton — alive. That means more cotton, better profits for Peter, and fewer chemicals in the environment.

Sounds great all round, right?

Well, Tasmanian farmer George Mills isn't buying it. He opposes GM not because he can't see the advantages of a drought, frost and weed resistant crop, but like the rest of Tasmanian farmers who are all GM free, he thinks the risks are just too high.

"Because I believe the research for both human consumption and for the environment hasn't been thoroughly tested enough and for long enough to make that switch to GM," he says.

And George is right to be worried, according to Bob Phelps, executive director of the GeneEthics Network. He says two recent studies on animals have linked GM foods with adverse effects on our immune systems: "The Russian study, which involved pregnant rats, showed that there were impacts on the offspring. So the young pups grew more slowly and their birth weights were very much lower, their mortality rates were much higher."

That's rats, but when it comes to long-term trials on humans, it's still early days.

So how much of our food is genetically modified? In fact, we grow only one major GM crop in Australia — cotton.

So fresh stuff, like fruit and veg, is completely clear of it. But GM food is imported, mainly from the US, in packaged or processed foods — things like oils, sugar in convenience food, soy and corn products.

By law it has to be labelled, but there's a loophole. Remember our GM cotton crop? Once the lint's been harvested, cottonseed is what's left — but it doesn't go to waste.

"The protein part of the plant or meal is also fed to livestock and the oil, of course, is used for cooking oil base in many parts of Australia and in many other food products," says Peter.

That cooking oil is used in some fried fast food snacks like sausage rolls, even biscuits. So you may be surrounded by GM foods and not know it, because by law they don't have to be labelled.

"Vegetable oils, sugars and starches as well as any food processing aids or additives and anything that's a product of an animal that's been fed on genetically engineered feed is also exempt from labelling," says Bob.

Why don't those foods have to be labelled?

Lydia Buchtmann from Food Standards Australia says it's because there's no way of telling what's GM and what's not.

"The states and territories' food departments or health departments enforce this and when they go out and inspect a supermarket they would be able to look at a GM oil and a non-GM oil and actually by testing you just couldn't tell the difference, so really it would be a law you couldn't enforce," she says.

So much for the current generation of GM foods. Andrew's next destination is the CSIRO labs in Canberra where he's meeting Dr Matthew Morell who is trying to create the next generation of GM plants — and these will be good for your health.

"Well the things that we're targeting are to try and reduce the onset of colorectal cancer, to reduce cardiovascular disease and to slow down the onset of type 2 diabetes," he says.

So for example, Dr Morell is working on making a low-starch, low-GI wheat, while in another glasshouse, they're crossing canola with Omega 3 oils taken from algae. Omega 3 is great for the heart and brain, but will all this messing about with a plant's DNA end up messing about with ours?

"No, that's one of the myths. When we eat that food none of the DNA is actually being transferred into our body," says Dr Morell.

So Dr Morell believes the new generation crops will be safe, but Bob Phelps remains sceptical about the GM industry's claims: "It's made an enormous number of promises about more productivity, about more nutritious food, about longer-shelf-life food and so on. None of these promises have come true."

So if you don't want to eat GM foods, what are your options?

Clearly the GM food debate is a hot potato. Both sides give good arguments — positives, negatives, advantages, disadvantages — and we'd all like to think that our food is as natural as possible, but does food production's future lie in science?

"Look I'm not convinced either way," says Andrew. "Ultimately you're going to have to make your own mind up."

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Fast facts

  • Some people believe that genetic modification of food reduces its nutritional value. False — the Food Standards Authority analyses all GM food for major nutrients, including amino acids, vitamins, minerals and fatty acids. They say there's no evidence that genetic modification reduces nutrient levels.

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