Sodium

Sodium is most commonly found in food as salt (sodium chloride). A small amount of sodium is required by the body as it plays an essential role in keeping the fluids and electrolytes in our bodies balanced. This is important when we exercise and sodium is lost through sweating.  However too much salt in our diet is associated with an increased risk of raised blood pressure, which is a risk factor for heart disease, stroke and kidney disease. Higher sodium intakes have been shown to increase calcium losses in the urine, potentially increasing the risk of osteoporosis.

How much sodium do we need?

 
Age (years)
RDI*
Sodium (mg/day)
Men 19-70+ 920-2300
Women 19-70+ 920-2300
* Recommended Daily Intake
 

Interestingly 2300mg is equivalent to 1teaspoon of salt. To convert between sodium and salt quantities multiply the sodium amount by 2.5. 

Who needs less and why?

In particular, people with high blood pressure need to watch how much sodium they eat. How blood pressure is affected by increases and reductions in sodium intake varies, depending on genetics, age, medications, ethnicity and medical conditions (such as Type 2 diabetes). Any decrease in sodium intake should be discussed with, and monitored by, your doctor.
However all New Zealanders should be encouraged to reduce their sodium intake as it has been determined that New Zealanders consume 3500mg of sodium per day (the equivalent of 1.5 teaspoons of salt) which is well over the recommended level of 2300mg. Being aware of the sodium content of the packaged and processed foods you are consuming is especially key to reducing your sodium intake as discussed below.

Which foods contain sodium?

Only 10% of salt consumed occurs naturally in food, with 15% of salt consumed added to food in cooking or at the table. This means most sodium in our diets comes from processed and manufactured food. This explains why it is recommended that we choose fresh food rather than processed foods.

When choosing packaged foods refer to the Nutrition Information Panel on the packaging. Sodium is listed in milligrams (mg) and by refering to the following classifcation system you can idenify whether the food is a low. medium or high salt food.

Low salt foods are those which contain less than 120mg of sodium per 100g of food

Medium salt foods contain between 120 and 600mg of sodium per 100g of food

High salt foods contain more than 600mg of sodium per 100g of food 
 

Sodium content of foods

  Sodium (mg) Classification
Fruit salad 1.2 Low
Sweetened Low Fat Yoghurt 47 Low
Instant Noodles 239 Medium
Multigrain bread 380 Medium
Fried Rice 411 Medium
Dried creme of chicken soup, made with water 287 Medium
Canned cream of chicken soup 460 Medium
Pizza, mixed toppings 640 High
Deep fried pork sausage 860 High
Salami 1850 High
Yeast extract spread 3300 HIgh
Tomato sauce 615 High
Potato chips 670 High

 

Tips for reducing sodium intake

  • Choose low-salt foods everyday: fruit and vegetables, lean meats, poultry, fish, seafood, plain wholegrain products, unprocessed breakfast cereals, and low-fat milk and dairy products.
  • Prepare meals without adding salt. Leave the salt shaker off the table, and use herbs and spices to add flavour instead.
  • All salt whether it is table salt, sea salt or rock salt contain sodium.

Concerns about sodium intake

If you are concerned about your salt or sodium intake, talk to your doctor.

The National Heart Foundation’s website, has information on salt and heart disease. You can also visit the Saltwise Challenge compiled by Stroke Foundation of New Zealand to check your knowledge of Sodium.

Click to view the page references

 

Page reviewed April 2013