Sodium is commonly found in food as salt (sodium chloride). It is an electrolyte needed both inside and outside of cells for fluid balance, energy transfer and the uptake of nutrients. Very small amounts of sodium are needed for adults and even less for children. Most people eat far too much of it.
Where can I get sodium (salt) from?
Salt is added to many foods to add flavour and can help to preserve the food to make it last longer. Foods high in salt include processed meats, tinned fish in brine, packaged snack foods, easy-cook packet foods such as instant noodles and rice risottos, bread and many types of crackers, pre-made sauces and flavour sachets, stocks and, of course, table salt.
What happens if I don’t eat enough sodium?
Sodium levels can fall after excessive exercise or sweating and lead to muscle cramps. Sodium can also be reduced through prolonged bouts of vomiting and diarrhoea. An electrolyte replacement drink may help correct this in both situations.
What happens if I eat too much sodium?
High intakes of sodium are linked to high blood pressure, a risk factor for developing kidney and cardiovascular disease, especially stroke. Reducing salt is an important goal and is now thought to be more important in its effects on reducing the risk of heart attacks and strokes than stopping smoking.
- If you are older, overweight or have high blood pressure, diabetes or chronic kidney disease you are more likely to be sensitive to the blood pressure-raising effects of salt.
- If others in your family have raised blood pressure in response to higher levels of sodium chloride, you may be more likely to as well. Diets high in potassium can help counteract this. This is best achieved by eating more fruits and vegetables.
- In people who do not have raised blood pressure, reduced sodium intake can decrease the risk of developing hypertension.
A 2007 World Cancer Research Fund study found both salt and foods preserved with salt are probably associated with an increased risk of stomach cancer.
Tips to lower your sodium intake
- Eat fresh foods where you can.
- Use fresh herbs and spices to flavour food instead of salt, stocks or soy sauce.
- If you add salt to your food, do so after cooking and once you’ve tried the food first so you don’t add too much.
- Limit packaged and processed foods as they will use added salt to flavour and preserve the food.
- Find low-salt snacks you enjoy such as fruit, unsalted nuts, plain & unsalted popcorn, yoghurt, biscuits and crackers low in sodium.
- Limit intake of salami, sausages, ham and other processed or cured meats.
- Choose vegetables and fish in canned spring water instead of brine.
- When shopping read labels for sodium content of foods:
- less than 120mg sodium per 100g are low salt choices and good to have everyday
- 120-600mg per 100g are medium salt choices and should be eaten only occasionally
- 600mg per 100g are high salt choices and should be avoided.
- Limit takeaways which are often high in salt and make these at home using fresh ingredients or ask for no added salt.
Sodium NZ Nutrition Foundation
Slash the salt NZ Stroke Foundation
Practical ways to reduce salt intake NZ Heart Foundation, 2015
Salt: Fact or Myth? NZ Heart Foundation
All of your questions about salt answered by a Nutritionist NZ Heart Foundation