We know foods like chips, pretzels and deli meats contain high levels of salt, but many people would be surprised to know sodium is lurking in unsuspecting items like bread, pasta sauce and salad dressing.
The most recent shocking salt discovery are ready meals found on the supermarket shelves, fridges and freezers, such as mac and cheese, noodle dishes and curries.
As part of the Unpack The Salt Campaign led by the Heart Foundation and VicHealth, The George Institute analysed nearly 1,500 ready meals from Woolworths, Coles, ALDI and IGA, and found some contained almost a whole day's worth of salt in just one serve. The average ready meal from the supermarket freezer, fridge and shelf contains 50 percent of an adult's recommended daily salt intake.
Seeing as convenience/ready meals are a booming industry (currently worth $900 million), this is a huge health worry.
To find out the supermarket meals containing the highest (and lowest) amount of salt, HuffPost Australia spoke to Clare Farrand, The George Institute's public health nutritionist and senior project manager for Salt Reduction.
Why is too much salt dangerous?
"At the moment we're all eating too much salt around the world," Farrand told HuffPost Australia. "There's a global target that we shouldn't eat any more than five grams of salt per day. In Australia we're eating about double this.
"Salt increases our blood pressure and this puts us at increased risk of stroke, heart attack and heart disease. These are called cardiovascular diseases which are the biggest killer worldwide."
The reason salt is a particular concern is there are no symptoms for high blood pressure, so you don't know you have the condition unless you get your blood pressure checked regularly.
Why is salt added to food?
Although salt is an effective preservative, the main reason food manufacturers add salt is to make food more tasty.
"This amount of salt isn't needed for preservative and texture. The amount of salt put in these meals is designed to improve or mask the taste," Farrand said.
"We have a drive to want to eat salt, and the more salt we eat the more we crave. Food manufacturers add lots of salt to food because it increases our drive to eat more of these foods. It hits those pleasure centres in our brain, much like sugar does."
What are the saltiest (and least salty) supermarket meals?
In the study the researchers looked at the highest and lowest salt content within the three ready meal categories: frozen, chilled and shelf.
"The results of our survey show the amount of ready meals in the store had more than doubled in the last seven years, and that ready meals are packed with salt," Farrand said.
"The average ready meal contains about half of our daily recommended maximum salt intake, and that's just in one meal -- we usually have three meals a day so this would certainly push us over our daily recommended limit. Even more staggering is some of the ready meals we surveyed contained an entire day's worth of salt in a single meal.
"These meals don't necessarily taste salty so many people aren't aware of how much salt the product really contains."
5 highest salt shelf ready meals (based on salt per 100g)
- Kraft Deluxe Mac and Cheese -- 783mg/100g sodium -- 1.96g/100g salt -- 4.42g salt per serve
- Harvest Braised Steak and Onion -- 638mg/100g sodium -- 1.60g/100g salt -- 3.39g salt per serve
- Wokka Shelf Fresh Noodles with Mi Goreng Sauce -- 630mg/100g sodium -- 1.58g/100g salt -- 5.51g salt per serve
- Maharajah's Choice Dhal Makhani -- sodium 590mg/100g -- 1.48g/100g salt -- 2.09g salt per serve
- Podravka Beef Goulash -- 535mg/100g sodium -- 1.34g/100g salt -- 2.01g salt per serve
5 lowest salt shelf ready meals (based on salt per 100g)
- Sun Rice Street Snack Chicken Satay -- 170mg/100g sodium -- 0.43g/100g salt -- 0.85g salt per serve
- Aldi Asia Specialities Hokkein Noodles with Peanut Satay Sauce -- 179mg/100g sodium -- 0.45g/100g salt -- 1.48 per serve
- SunRice Thai Style Chicken Satay Curry with Rice -- 193mg/100g sodium -- 0.48g/100g salt -- 1.69g salt per serve
- John West Tuna and Rice Chilli and Tomato -- 194mg/100g sodium -- 0.49g/100g salt -- 0.97g salt per serve
- John West Tuna Brown Rice and Quinoa Thai Red Curry -- 195mg/100g sodium -- 0.49g/100g salt -- 0.98g salt per serve
5 highest salt chilled ready meals (based on salt per 100g)
- Brubecks Boutique Foods Kato Organic Soba Noodle Salad with Teriyaki Dressing -- 828mg/100g sodium -- 2.07g/100g salt -- 4.14g salt per serve
- Quick as Wok Chicken Teriyaki -- 780mg/100g sodium -- 1.95g/100g salt -- 5.85g salt per serve
- Brubecks Boutique Foods Chinese Style Egg Noodle Salad with Fresh Vegetables and Sesame Soy -- 724mg/100g sodium -- 1.81g/100g salt -- 3.62g salt per serve
- Quick as Wok Beef Rendang -- 657mg/100g sodium -- 1.64g/100g salt -- 4.93g salt per serve
- Spice and Passion Thai Green Chicken Curry -- 540mg/100g sodium -- 1.35g/100g salt -- 4.73g salt per serve
5 lowest salt chilled ready meals (based on salt per 100g)
- My Pasta Box Classic Tomato and Basil Penne -- 37mg/100g sodium -- 0.09g/100g salt -- 0.26g salt per serve
- Fresh Fodder Milk Chicken and Rice Curry -- 65mg/100g sodium -- 0.16g/100g salt -- 0.49g salt per serve
- Woolworths Delicious Nutritious Michelle Bridges Beef and Barley Casserole with Roasted Vegetables -- 102mg/100g sodium -- 0.26g/100g salt -- 0.89g salt per serve
- My Pasta Box Rich Bolognese Rigatoni -- 104mg/100g sodium -- 0.26g/100g salt -- 0.73g salt per serve
- Fresh Fodder Beef and Pasta Bolognese with Red Wine -- 133mg/100g sodium -- 0.33g/100g salt -- 1g salt per serve
5 highest salt frozen ready meals (based on salt per 100g)
- CP Authentic Asia Prawn Wonton Tom Yum Ramen Soup -- 595mg/100g sodium -- 1.49g/100g salt -- 4.79g salt per serve
- Super Nature Middle Easter Chciek with Quinoa Tabbouleh -- 504mg/100g sodium -- 1.26g/100g salt -- 4.41g salt per salt
- On the Menu All Day Breakfast -- 491mg/100g sodium -- 1.23g/100g salt -- 3.93g salt per serve
- Super Nature Chicken Pad Thai with Rice Noodles -- 490mg/100g sodium -- 1.23g/100g salt -- 4.29g salt per serve
- On the Menu Beef Schnitzel -- 405mg/100g sodium -- 1.01g/100g salt -- 3.24g salt per serve
5 lowest salt frozen ready meals (based on salt per 100g)
- The Sultan's Kitchen Butter Chicken -- 84mg/100g sodium -- 0.21g/100g salt -- 0.53g salt per serve
- McCain Healthy Choice Lemon Chicken with Asian Veg and Rice-- 90mg/100g sodium -- 0.23g/100g salt -- 0.79g salt per serve
- The Good Meal Co. Gluten Free Risotto Primavera -- 94mg/100g sodium -- 0.24g/100g salt -- 0.88g salt per serve
- Super Nature Beef, Kale and Red Quinoa Lasagne -- 129mg/100g sodium -- 0.32g/100g salt -- 1.13g salt per serve
- International Cuisine Beef in Red Wine Sauce with Mash -- 130mg/100g sodium -- 0.33g/100g salt -- 0.98g salt per serve
It's important to note this study analysed the salt content, not the overall nutrition, in ready meals.
Tips for reducing salt intake
1. Read the labels. Choose lower salt options by comparing the sodium content in the 'per 100g' column on the nutrition information panel. Low salt/sodium is considered to be less than 130mg per 100 grams. Up to 400mg is an 'okay' option;
2. Eat more fresh foods and reduce intake of processed and packaged foods;
3. Use herbs and spices for flavour instead of relying on salt when cooking at home;
4. Use the FoodSwitch app when food shopping to scan and find food products with lower sodium content.