04/10/2016 4:40 PM AEDT | Updated 14/03/2017 10:41 AM AEDT

How Much Gluten Is Actually In Gluten-Free Foods?

The answer isn't always on the packet.

Diane Macdonald
Gluten free is not as simple as being free from gluten.

A packet of biscuits or bread may be labelled gluten free, but that doesn't actually mean there's no gluten in it.

In fact a new Australian study has found 14 percent of imported 'gluten-free' foods contain so much gluten that they wouldn't comply in Australia.

University of Western Australia clinical professor Geoff Forbes told The Huffington Post Australia he began paying close attention to gluten when two of his children were diagnosed with coeliac disease -- which causes the immune system to react to gluten.

He said it was not so easy to create a product that's entirely free from gluten.

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Gluten free food does sometimes contain some gluten.

"In Australia, gluten-free standards were set in 1995 and at that time, 'gluten free' meant no detectable gluten but laboratories could really only detect around 30 parts of gluten per million," Forbes said.

"So there was a very small amount of gluten in gluten-free products. Over time, the ease with which laboratories can detect gluten has improved. It's now possible to detect it down to three parts per million."

Globally, foods need to have less than 20 parts per million gluten to be considered gluten free, while in Australia, none can detected at all.

Actually I was quite surprised at how good the results were.

Forbes and his team bought 169 imported 'gluten-free' foods from Europe, Asia and America including bread, biscuits, cereals, flours, condiments, pasta, drinks and confectionery. They detected gluten in 24 products, but at very low levels.

"Actually I was quite surprised at how good the results were," he said.

As for which brands did and didn't contain gluten, Forbes said the information was passed on to the regulatory authority and it was their responsibility to deal with the brands.

"There isn't actually a way coeliac patient can find out specifically how much gluten is in a product," he said.