When it comes to putting a piece of sushi into a soy sauce tray, most of us don't think about it anymore.
But according to a new study by The George Institute for Global Health, VicHealth and the Heart Foundation, some of your favorite Asian sauces – including soybeans, oysters and fish – contain far more salt than you think.
Looking at 150 different sauces, research shows that one tablespoon of soy sauce on average contains 61 percent of the recommended daily salt intake. Or, if you only use one packet of soy sauce on sushi rolls, you will consume almost 10 percent of your daily salt intake.
This research lasted eight years between 2010 and 2018, and showed that of all Asian sauces analyzed, fish sauce contained the highest salt content.
A tablespoon of popular Asian ingredients contains 96 percent of the average recommended daily salt intake.
"We know that stir-fried dishes are really popular because they are fast, fresh and healthy but too many of us don't realize how much salt is hidden in the sauce we use," said Heart Foundation Dietitian Sian Armstrong.
"A tablespoon of the most salty soy sauce contains nearly 90 percent of the recommended daily salt intake, while the lowest soy sauce has less than half of it.
"Too much salt can cause high blood pressure, which increases the risk of stroke, heart disease and kidney disease. One of the best ways to keep your blood pressure down is to eat less salt so choose salt-less soy sauce when you cook stir-fry and go with easy on the sauce. "
On average, one tablespoon of soy sauce contains 61 percent of the maximum recommended daily salt intake.
According to the study, one packet of soy sauce can contain nearly 10 percent of the recommended maximum daily salt intake, while the salty soy sauce on supermarket shelves is Chang's mild soy sauce, which has more than double the amount of salt as the lowest, soy sauce. Kikkoman is naturally brewed with a little soy sauce.
Oyster sauce has the lowest salt per tablespoon, although on average it still has 36 percent of the recommended daily intake.
"In the past decade we have not seen a reduction in the amount of salt in this sauce and there is no target to produce change," the report's lead author, Clare Farrand, said in a statement.
"People think soy sauce can't be made saltier, but this report shows that it doesn't happen, with some soy sauce, tamari and oysters that contain much lower levels of salt. We want to see all
producers reduce salt levels in their sauces – that can be done. "
Earlier this year, a controversial new study found that not having enough salt in your diet might actually be bad for you and suggesting a campaign that tells people to reduce salt might only be worth it in countries with very high sodium consumption.
The World Health Organization recommends limiting salt consumption at 5g per day – about one teaspoon – because of the risks associated with increased blood pressure and stroke.
But this unknown target has been reached anywhere in the world, note the study authors published in The Lancet medical journal.
"We should be more concerned about targeting people and countries with high average sodium intake – above 5g (equivalent to 12.5 g of salt), such as China – and bringing them to a moderate range" from 7.5 to 12, 5 g of salt, said lead author Andre Mente, a professor at the Population Health Research Institute at McMaster University in Canada.
According to the Heart Foundation, Australia consumes two teaspoons of salt (10 g) per day on average.
"Nearly six million Australians aged 18 and over have high blood pressure, this represents 34 percent of the adult population," said Heart Foundation prevention director Julie-Anne Mitchell, told News Corp Australia.
The Heart Foundation recommends a diet high in vegetables, wholegrain, nuts, beans, healthy oils and various lean proteins including fish, lean meat, poultry and low-fat dairy products.
"By adopting a heart-healthy diet, which includes a combination of foods that are chosen regularly over time, Australians can reduce their salt intake," Mitchell said.