Sodium is an electrolyte – a nutrient that plays a critical role in the way water is distributed throughout the body. It’s therefore important for maintaining extracellular fluid volume and plasma volume. Sodium is consumed as sodium chloride (table salt), sodium bicarbonate (baking powder), sodium phosphate, sodium carbonate etc.
Sodium and blood pressure
Dietary sodium is only one of the factors that can affect blood pressure. Excess weight and lack of regular exercise are also important factors.
Excess salt promotes fluid retention and increases blood volume, forcing the heart to work harder. As well as decreasing dietary sodium, the National Heart Foundation recommends eating plenty of fresh fruit and vegetables in order to ensure a good intake of potassium. Potassium helps the body excrete more sodium, and therefore the sodium to potassium ratio of the diet is just as important as the total sodium intake.
Health experts also agree that losing weight (if you are overweight) and increasing your level of physical activity are the most important things you can do if you have high blood pressure. Limiting alcohol is also advised.
How much to aim for?
Most diets have ample amounts of sodium to meet electrolyte needs. The National Health and Medical Research Council has set the maximum recommended dietary intake (RDI) for sodium at 900-2300mg sodium per day (40-100mmol/day) for adults. This equates to about 7 g of common salt or about 1 ½ teaspoons per day.
Tips for moderating your sodium intake
Here are some ways to moderate the amount of sodium in your diet:
- Cut back on the amount of salt you use in cooking and at the table. To make foods flavoursome, try using salt-free seasoning mixes, low salt sauces, fresh herbs, and spices like chilli, garlic or ginger.
- Look for salt reduced foods. These foods may be labelled as “reduced sodium”, “ salt reduced”, “low sodium”, “lightly salted”, or “no added salt ”. Read and compare the Nutrition Information panel on food packets to see how much sodium the food contains per serving. Campbell’s has launched Chunky Salt Reduced Beef, Country Ladle Salt Reduced Minestrone, and V8 low sodium Vegetable Juice.
- Practice portion control. When choosing your meals, keep portions of higher sodium foods smaller in relation to portions of low–sodium foods.
- Balance high-sodium meals with lower-sodium ones. For example, if you know your lunch will include higher-sodium foods, choose lower-sodium foods at breakfast and dinner to balance your daily intake. High sodium foods include certain meats, for example, ham, bacon, salami and take away foods.
- Persevere. Although a lower salt diet may taste odd at first, be assured that your taste buds will adjust over time.