The role of salt in our food and body

Dietitian, Annica Rust, helps us understand why the body needs salt as well as why too much is dangerous.

Salt (sodium chloride) is important for your body as it performs vital functions, but consuming more than your daily requirements can be harmful. Most people consume on average 9-12 grams of salt per day, which is double the recommended maximum intake.3 It’s therefore no surprise that 13% of deaths caused globally are by high blood pressure and that on average 225 South Africans are killed by heart disease every day.5

The role of salt in food

Salt is commonly used to enhance the flavour of food, in addition to its commonly known benefit of being a preservative, which inhibits bacteria growth and increases the freshness and shelf life. Salt is also used to improve the texture and appearance of food.1,2

The role of food in our body

The human body needs a small amount of salt to perform vital functions, such as conducting nerve impulses, contracting and relaxing muscles and to maintain the water and mineral balance in the body.1

How much salt is needed to maintain the vital functions?

We need a minimum intake of 500mg of sodium (1/4 teaspoon of salt) a day to perform vital functions2, however it’s recommended that adults don’t exceed 2000 mg of sodium which is equal to 5 grams/1 teaspoon of salt per day. This will prevent high blood pressure (hypertension) and the associate risks of cardiovascular disease, strokes and heart attacks.

Eating too much salt

With a high intake of sodium, your kidneys can’t keep up to excrete the excess sodium in the blood and sodium will accumulate in the bloodstream. To compensate for this, your body will retain additional water to dilute the sodium. However, this in turn will increase your blood volume.

An increase in your blood volume will put unnecessary strain on your heart as it needs to work harder, which over time contributes to high blood pressure. High blood pressure further increases the risk for a heart attack, stroke and cardiovascular conditions. This is especially a problem if you have diabetes, which already places you at an increased risk of a heart attack, stroke and cardiovascular disease. 1,2

High blood pressure also increases the risk for chronic kidney disease and osteoporosis. Osteoporosis occurs with a high intake of salt which can further increase the amount of calcium that is excreted via urination, causing low blood calcium levels. Low blood calcium levels will result in the breakdown of bone to release the necessary calcium in the bloodstream to maintain blood calcium levels.1

 Steps to reduce your salt intake

  1. Reduce processed and restaurant/fast food

Processed and restaurant foods accounts for more than 70% of the sodium intake of Americans. Cutting down on processed foods will therefore be beneficial to lower your salt intake.6

Processed foods
Meats & cheese Salami, bacon, sausages, viennas, polony, ham, biltong and smoked chicken, cheese
Carbohydrates Breakfast cereals, bread, crisps, pies, cakes, biscuits
Vegetables & fruits Tinned vegetables and fruits
Meals Ready-made meals and microwave meals


  1. Label reading & logo identification

It’s valuable to look at labels, especially the nutritional information table as well as the ingredients listed when deciding which product to buy.

When comparing products, look at the amount per 100g and not the amount per serving. When looking at the ingredient list look out for sodium, monosodium glutamate (MSG), baking soda or sodium bicarbonate or any words containing the term sodium, nitrites, nitrates and salt.

The order in which the ingredients are listed is important as it serves as a rough indication as to how much of that ingredient is in the product. Ingredients will always be listed in descending order of weight (largest to smallest weight). Usually, the first three ingredients that appear in the list make up the largest portion of the product. Make sure that salt is not one of top three ingredients.4

Nutritional Information Table
                 Description Sodium (salt) per 100g

Avoid or limit intake

> 600mg

Eat seldom

120 – 600mg

Healthier option – eat often

< 120mg

Look out for food items with the Heart and Stroke Foundation South Africa logo, given that these food items will be lower in sodium when compared to similar products.


  1. Stop using the salt shaker on the table 

  1. Reduce the amount of salt when cooking, by using more herbs, unsalted spices and strong flavoured food components to flavour your food.


Herbs, unsalted spices and flavourings4
Lemon juice and vinegar

Mixed herbs, basil, bay leaves, parsley, thyme, sage, dill and rosemary

Curry powder, turmeric, nutmeg, paprika and pepper

Garlic, ginger, chives, spring onions and onions


  1. Be aware of hidden sodium

Many food items already have a high amount of sodium included, such as bread, breakfast cereals, processed meats and sausages, stock, soup and gravy powders as well as brick margarine.4

When in doubt contact a registered dietitian for assistance. For more information on sodium, please visit The Heart and Stroke Foundation of South Africa


  1. [10 February 2022]
  2. Centers for Disease Control and Prevention. 2022. [9 February 2022]
  3. World Health Organisation. 2020. [10 February 2022]
  4. Salt watch: [10 February 2022]
  5. Heart & Stroke Foundation. 2022.
  6. American Heart Association.[10 February 2022]


Annica Rust is a registered dietitian practicing at the Breast Care Unit in Netcare Milpark Hospital as well as in Bryanston. She assists with medical nutritional therapy for cancer prevention, treatment, survivorship and palliation. She gives individualised nutritional care to prevent or reverse nutrient deficiencies, nutrition-related side effects and malnutrition to maximise quality of life.

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