Sodium regulates body water content and electrolyte balance. During exercise, when sweating is involved, sodium regulates the requirements for water and salts. Sodium is also is involved in energy use and nerve function.

Sodium is a major component of salt. 1 g of salt contains 0.4 g sodium.

High sodium intake is associated with high blood pressure, which is an important risk factor for cardiovascular (heart) disease, particularly stroke. The effect of sodium on blood pressure varies according to age and each individual's blood pressure.

The Recommended Daily Intake for sodium intake in New Zealanders is 920 to 2300 mg per day. A study completed in 1998 indicated that New Zealanders' consumption of sodium was much higher, with an average intake of 3473 mg per day.

Sodium is often added during food processing, with approximately 85% of the average daily sodium intake coming from processed foods. Individuals can restrict their sodium intake by avoiding salty foods and by not adding salt during cooking or to a meal.

Bread or sodium

Salt is added to bread to enhance the flavour and aid in its processing. In recent years, New Zealand bread producers have lowered the amount of salt added to bread to reduce the sodium levels. Bread contains on average less than 550 mg sodium per 100 g. This is equivalent to approximately 1.4 g salt per 100 g of bread.

Breads containing soy and linseed targeted at women seem to contain lower levels of sodium, for example Molenberg Vital contains only 390 mg sodium per 100 g and Burgen Soy-Lin contains 366 mg per 100 g. The Vogel's range also has lower sodium added, in the range of 380 mg per 100 g.