What do eight packets of Smith's salted potato crisps and two Big Macs have in common?

Both have less salt than an average packet of instant noodles sold in Australia.

It was a finding that stunned researchers at The George Institute for Global Health, when they surveyed 765 noodle products collected from 10 countries between 2012 and 2016; including Australia, China, Costa Rica, Fiji, India, Indonesia, New Zealand, Samoa, South Africa and Britain.

Among the sample set, salt levels in Australian instant noodles were the second highest, with an average packet containing more than 80 per cent of the daily recommended maximum salt intake of five grams a day.

Aldi's Simplee 2 Minute Noodles (chicken flavour) was declared Australia's "worst offender" because, based on the serving size provided on the pack, it contained 2.67 grams of salt per serving, more than half a day's worth of salt.

However, if comparing levels based on grams of salt per 100 grams, then Maggi Mi Goreng Fusion Soy & Mild Spice​ would be considered the most salty, despite ranking as one of the lowest, based on labelled salt per serve.

"This shows just how confusing it can be for consumers, because there is no clear and consistent labelling on instant noodles," said Clare Farrand, public health nutritionist at The George Institute.

"There is a huge amount of salt in a serving of noodles, but what is more worrying is that in reality people tend to eat the entire packet of noodles, rather than just the recommended serving size, eating even more salt than what is advertised."

A spokeswoman for Maggi said the sodium listed on the back of Maggi packs was not all sourced from table salt, but also came from other ingredients within the product.

"We recognise that this category is relatively high in sodium and we have taken significant steps over a number of years to address this," she said.

"Over the last two years we have reduced sodium in our biggest selling product, Maggi 2 Minute Noodles (chicken) by 26 per cent. We will continue to make improvements to the recipe across the entire Maggi 2 Minute range, reducing sodium by up to 20 per cent over the next three years."

German discount giant Aldi, which manufactures Simplee​ noodles, said it had reviewed the salt content contained in the product range and  was "currently working with suppliers to improve the products".

"Aldi's range is extremely dynamic, regularly adapting to match the changing tastes and needs of customers," a spokeswoman said. "We take market cues on labelling and branding and ensure we carry out due diligence when developing packaging of all of our products and labels."

But the fact that individual brands and manufacturers maintain their own labelling standards only causes confusion for consumers, The George Institute found, as some brands listed sodium information "as sold", while others referred to the "as prepared" amount, after water and flavouring are added.

The study also revealed large variations in the amount of salt in instant noodle products around the world. For example, the noodle product with the highest sodium content per 100g was found in Indonesia, containing 7584 milligrams per 100 grams, almost 30 times the amount of sodium found in those with the lowest sodium content in New Zealand, with 249 milligrams per 100 grams.

National food spokesperson for The Heart Foundation Kellie-Ann Jolly said the data did not come as a surprise.

"We've known for some time that about three-quarters of the salt we consume comes from processed foods with most of it hidden in everyday products, including in family favourites like two-minute noodles."

Ms Jolly said, with more than half of Australia's adults exceeding the recommended daily intake of salt, it was vital the nation reduced its salt consumption.

"The problem is that eating too much salt can increase your risk of high blood pressure, which is a significant risk factor for heart disease, the single biggest killer in Australia."

The Heart Foundation has been working with the food industry to make processed foods healthier.

Oriental Merchant, which imports Indo Mie noodles into Australia, was contacted for comment.

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