Salt
[3] It is used to produce caustic soda and chlorine, and in the manufacture of products such as polyvinyl chloride, plastics, and paper pulp.
Accordingly, numerous world health associations and experts in developed countries recommend reducing consumption of popular salty foods.
[6][7] The World Health Organization recommends that adults consume less than 2,000 mg of sodium, equivalent to 5 grams of salt, per day.
[11] A very ancient salt-works operation has been discovered at the Poiana Slatinei archaeological site next to a salt spring in Lunca, Neamț County, Romania.
Evidence indicates that Neolithic people of the Precucuteni Culture were boiling the salt-laden spring water through the process of briquetage to extract salt as far back as 6050 BC.
[13] The harvest of salt from the surface of Xiechi Lake near Yuncheng in Shanxi, China, dates back to at least 6000 BC, making it one of the oldest verifiable saltworks.
Each camel takes two bales of fodder and two of trade goods northwards and returns laden with salt pillars and dates.
[24] In Gabon, before the arrival of Europeans, the coast people carried on a remunerative trade with those of the interior by the medium of sea salt.
[25] Salzburg, Hallstatt, and Hallein lie within 17 km (11 mi) of each other on the river Salzach in central Austria in an area with extensive salt deposits.
Salt crystals are translucent and cubic in shape; they normally appear white but impurities may give them a blue or purple tinge.
[39] Some table salt sold for consumption contains additives that address a variety of health concerns, especially in the developing world.
Iodine is an important micronutrient for humans, and a deficiency of the element can cause lowered production of thyroxine (hypothyroidism) and enlargement of the thyroid gland (endemic goitre) in adults or cretinism in children.
In the United States, the Food and Drug Administration (FDA) recommends 150 micrograms of iodine per day for both men and women.
[3] Another additive, especially important for pregnant women, is folic acid (vitamin B9), which gives the table salt a yellow colour.
Folic acid helps prevent neural tube defects and anaemia, which affect young mothers, especially in developing countries.
[3] Unrefined sea salt contains small amounts of magnesium and calcium halides and sulfates, traces of algal products, salt-resistant bacteria and sediment particles.
Since taste and aroma compounds are often detectable by humans in minute concentrations, sea salt may have a more complex flavour than pure sodium chloride when sprinkled on top of food.
This product absorbs minerals from the bamboo and the mud, and has been claimed to increase the anticlastogenic and antimutagenic properties of doenjang (a fermented bean paste).
The main sources of salt in the Western diet, apart from direct use, are bread and cereals, meat, and dairy products.
[65] In the United States, 75% of the sodium eaten comes from processed and restaurant foods, 11% from cooking and table use and the rest from what is found naturally in foodstuffs.
[66] Because consuming too much sodium increases risk of cardiovascular diseases,[6] health organizations generally recommend that people reduce their dietary intake of salt.
[4][6] In adults and children with no acute illness, a decrease in the intake of sodium from the typical high levels reduces blood pressure.
[71][72] The World Health Organization recommends that adults should consume less than 2,000 mg of sodium (which is contained in 5 g of salt) per day.
[68] Another review indicated that there is inconsistent/insufficient evidence to conclude that reducing sodium intake to lower than 2,300 mg per day is either beneficial or harmful.
"[75] The findings showed that increased mortality from excessive salt intake was primarily associated with individuals with hypertension.
[87] The world's oceans are a virtually inexhaustible source of salt, and this abundance of supply means that reserves have not been calculated.
[92] The Khewra Salt Mine in Pakistan has nineteen storeys, eleven of which are underground, and 400 km (250 mi) of passages.
The salt is dug out by the room and pillar method, where about half the material is left in place to support the upper levels.
Uses include the tale of how Lot's wife is turned into a pillar of salt when looking back at the cities of Sodom and Gomorrah as they are destroyed.
When returning home from a funeral, a pinch of salt is thrown over the left shoulder as this prevents evil spirits from entering the house.
