Common salt used to flavour food and as a preservative. Table salt consists mainly of sodium chloride, but may also contain other chemicals such as anti-caking agents (e.g. magnesium carbonate and sodium hexacyanoferrate II).
Many table salts are also iodized (they have iodine added). Iodization was first carried out in the USA in the 1920s to combat goitre (an abnormal enlargement of the thyroid gland). However, except in the northernmost States where the levels of iodine in the soil are abnormally low, most people can obtain sufficient iodine from a normal balanced diet without using iodized salt.
For several years doctors have expressed concern about the overconsumption of salt because of its high sodium content (approximately 40 per cent). A high dietary intake of sodium salts is associated with high blood pressure and heart disease. Some patients suffering hypertension can reduce their blood pressure by taking a low-salt diet. The WHO recommends that total salt consumption should be around 5 g per person per day. Current intakes in the UK are around 8–10 g of salt each day. In the USA warnings about the hazards of salt consumption have resulted in a remarkable response: although still exceeding 5 g per day, the intake of salty products has decreased by more than 30 per cent and the food industry is processing many more foods with low salt levels.
Subjects: Medicine and Health.