Researchers looked at more than 1,400 bread products from 2010 to 2017 and found some had a large amount of sodium.

Lead researcher Clare Farrand said a typical single slice of bread contained more than 20 per cent of the recommended daily maximum of salt..

"That was double the amount of salt [compared to] a single serving packet of Kettle sea salt chips," she said.

Ms Farrand said another concerning find was that some "healthy" breads were some of the worst offenders.

"Rye bread, and potentially wraps, actually came up as some of the highest-salt products."

Products looked at by researchers included bread rolls, fruit bread, multigrain bread, other grain breads, rye bread, soy and linseed bread, white bread, wholemeal bread, bagels, crumpets and English muffins.

Ms Farrand said they also found there was a huge amount of variability of salt between bread products.

"You could actually be eating far more salt from one bread [product, when] compared to another," she said.

She said there were lower salt options available, and suggested consumers get in the habit of checking the label before buying a product and choosing the lower salt option.

"It is often down to a taste preference," she said.

"Some breads contain more salt than others as a result of the amount of salt that the manufacturer is putting in."

She said their research showed bread could be produced with much less salt than was currently being used.

"We're all trying to reduce the amount of salt that we eat, because salt puts up our blood pressure," she said.

"And raised blood pressure is a major risk for strokes, heart attacks and heart disease — which is the number one killer worldwide.

"In Australia, like many countries around the world, we're eating far too much salt."

The study recommends a reduction of sodium in bread products.

Bread salt levels fell after targets were set

The study found that since 2010, salt levels in bread had dropped by about 10 per cent.

But Ms Farrand said while it proved that salt targets for breads did work, the number needed to fall further.

"The Government did set salt targets as to the amount of salt in bread, and manufacturers worked to achieve those targets.

"And we were able to see for breads which did actually have salt targets, about 81 per cent of bread products met those targets.

"However there are a lot of bread products on the market that don't have salt targets.

"What we really need is for all bread to have salt targets and all breads to reduce the amount of salt in them so that we can all enjoy the health benefits of eating less salt."

The Heart Foundation's Roni Beauchamp said she was not surprised by the findings.

She said on average most Australian adults were consuming between eight and ten grams of salt each day.

That is nearly double the recommended maximum daily intake of about five grams, "or about a teaspoon a day."

"And even in children, we've got children consuming probably about 30 per cent more than would be recommended, so it is a critical issue," she said.