If, as the saying goes, we are what we eat, wouldn't you want to know exactly what you're eating? Melanie Murphy went on the hunt to discover what's in genetically modified foods.

What are you eating

We're bombarded with choices every time we reach to put an item in our trolleys - fresh, frozen; organic, non-organic; farm laid, battery laid; Australian made, imported - and to add to the confusion we now have the option of genetically modified (GM) or GM-free foods. But unless you study food labels or are in the know about the GM foods that don't required labelling, the choice isn't that simple. The reality is, you've probably been unassumingly eating GM food sources for years, as it can be present in chocolate, biscuits, mayonnaise, bread, corn chips - and even in deep-fried fish 'n chips from your local takeaway.

In Australia, 33 GM food sources are approved for sale, including soybean, canola, corn, potato, sugar beet and cotton seed. These are all imported, with the exception of GM cotton, which is the only GM crop commercially grown in Australia. It enters our food supply as cotton seed oil or vegetable oil.

GM foods, also known as genetically engineered (GE) foods, contain ingredients that have been modified by gene technology. This allows food producers to alter certain characteristics of a food crop by introducing genetic material and proteins from another source. In the future, genetic modification may be used to improve a food's flavour or nutritional properties. Currently it is used to improve a plant's growing characteristics to be pest-resistant or herbicide-tolerant.

While being pest-resistant or herbicide-tolerant has its benefits, the question is - are GM foods safe to eat? Food Safety Australia New Zealand (FSANZ) spokesperson Lydia Buchtmann, says GM foods are thoroughly tested to determine if they are fit for human consumption. "When we do a safety assessment, we compare GM foods with their (non-GM) equivalent for nutrition and safety," she says. The assessment also considers differences from a molecular, toxicological and compositional point of view. If the genetic modification does not cause any additional health risks, it will be approved. "Provided a safety assessment has been conducted by us (FSANZ) and we find the food safe, then GM food is safe to eat. I would point out that GM foods have been on the market in the US for over 10 years. There's never been a reported case of illness relating to GM foods."

However, Institute of Health and Environmental Research director Dr Judy Carman, believes the testing procedure is not adequate, which is why she opts to avoid GM foods where possible. "When I eat in my own home I eat olive oil instead of canola oil, butter instead of margarine, and I look at labels to see if there's any soy or maize," she says.