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{{About|common table salt|salts in chemistry|Salt (chemistry)|table salt used in chemistry|Sodium chloride|the film Salt|Salt (2010 film)|other uses}}
#REDIRECT [[Sodium chloride]]
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[[File:DeadSeaIsrael5.jpg|thumb|Salt deposits beside the [[Dead Sea]]]]
[[File:2015-03-07 Pakistanisches, sogenanntes Himalaya-Salz 0399.jpg|thumb|Red rock salt from the [[Khewra Salt Mine]] in Pakistan]]

'''Table salt''' or '''common salt''' is a [[mineral]] composed primarily of [[sodium chloride]] (NaCl), a [[chemical compound]] belonging to the larger class of [[Salt (chemistry)|salts]]; salt in its natural form as a [[crystallinity|crystalline]] mineral is known as rock salt or [[halite]]. Salt is present in vast quantities in [[seawater]], where it is the main mineral constituent. The open ocean has about {{convert|35|g|oz}} of solids per litre, a [[salinity]] of 3.5%.

[[Sodium in biology|Salt is essential for life in general]], and saltiness is one of the [[Basic tastes|basic human tastes]]. The tissues of [[animal]]s contain larger quantities of salt than do [[plant]] tissues. Salt is one of the oldest and most ubiquitous food seasonings, and [[Salting (food)|salting]] is an important method of [[food preservation]].

Some of the earliest evidence of salt processing dates to around 8,000 years ago, when people living in an area in what is now known as the country of [[Romania]] were boiling [[spring (hydrology)|spring water]] to extract the salts; a [[Salt in Chinese History#Ancient China and the early empire|salt-works in China]] dates to approximately the same period. Salt was also prized by the ancient Hebrews, the [[Ancient Greece|Greeks]], the Romans, the [[Byzantine Empire|Byzantines]], the [[Hittites]], [[Ancient Egypt|Egyptians]], and the [[Ancient India|Indians]]. Salt became an important article of trade and was transported by boat across the Mediterranean Sea, along specially built salt roads, and across the Sahara in camel caravans. The scarcity and universal need for salt has led nations to go to war over it and use it to raise tax revenues. Salt is used in religious ceremonies and has other cultural significance.

Salt is processed from [[salt mining|salt mines]], or by the [[evaporation]] of seawater ([[sea salt]]) or mineral-rich spring water in shallow pools. Its major industrial products are [[caustic soda]] and [[chlorine]], and is used in many industrial processes including the manufacture of [[polyvinyl chloride]], [[plastic]]s, [[paper pulp]] and many other products. Of the annual global production of around two hundred million [[tonne]]s of salt, only about 6% is used for human consumption. Other uses include water conditioning processes, [[de-icing]] highways, and agricultural use. Edible salt is sold in forms such as sea salt and table salt which usually contains an [[anti-caking agent]] and may be [[iodised salt|iodised]] to prevent [[iodine deficiency]]. As well as its use in cooking and at the table, salt is present in many processed foods.

Sodium is an [[essential nutrient]] for human health via its role as an [[electrolyte]] and [[osmosis|osmotic solute]].<ref name=USDA2015/><ref name="IOM2013">{{cite web|url=http://books.nap.edu/openbook.php?record_id=18311|title=Sodium intake in populations: assessment of evidence|year=2013|publisher=Institute of Medicine of the National Academies|editor-first1=Brian L.|editor-last1=Strom|editor-first2=Ann L.|editor-last2=Yaktine|editor-first3=Maria|editor-last3=Oria|accessdate=17 October 2013}}</ref><ref name=CDC/> Excessive salt consumption can increase the risk of [[cardiovascular diseases]], such as [[hypertension]], in children and adults. Such [[health effects of salt]] have long been studied. Accordingly, numerous world health associations and experts in developed countries recommend reducing consumption of popular salty foods.<ref name=CDC/><ref name="efsa">{{cite web | url=http://www.efsa.europa.eu/en/press/news/nda050622 | title=EFSA provides advice on adverse effects of sodium | publisher=European Food Safety Authority | date=22 June 2005 | accessdate=9 June 2016}}</ref> The [[World Health Organization]] recommends that adults should consume less than 2,000&nbsp;mg of sodium, equivalent to 2&nbsp;grams of salt per day.<ref>{{Cite web |title=WHO issues new guidance on dietary salt and potassium |url=http://www.who.int/mediacentre/news/notes/2013/salt_potassium_20130131/en/ |date=31 January 2013 |publisher=[[World Health Organization|WHO]]}}</ref>

==History==
{{Main article|History of salt}}

[[File:Salzproduktion-Halle.jpg|thumb|Salt production in [[Halle, Saxony-Anhalt]] (1670)]]
Humans have always tended to build communities either around sources of salt, or where they can trade for it.

All through history the availability of salt has been pivotal to civilization. The word "[[salary]]" comes from the [[Latin]] word for salt because the [[Roman Legion]]s were sometimes paid in salt.<ref>{{cite web|url=http://www.etymonline.com/index.php?search=salary|title=Online Etymology Dictionary|publisher=|accessdate=5 March 2016}}</ref> The [[Natron Valley]] was a key region that supported the [[Egyptian Empire]] to its north, because it supplied it with a kind of salt that came to be called by its name, [[natron]].

Even before this, what is now thought to have been the first city in Europe is [[Solnitsata]], in [[Bulgaria]], which was a salt mine, providing the area now known as the [[Balkans]] with salt since 5400 BC.<ref>LA Times<br />[http://articles.latimes.com/2012/nov/01/science/la-sci-sn-oldest-european-town-20121101 Bulgarians find oldest European town, a salt production center]</ref> Even the name Solnisata means "salt works".

While people have used [[canning]] and artificial [[refrigeration]] to preserve food for the last hundred years or so, salt has been the best-known food preservative, especially for meat, for many thousands of years.{{sfn|Barber|1999|p=136}} A very ancient salt-works operation has been discovered at the Poiana Slatinei archaeological site next to a salt spring in [[Vânători-Neamţ|Lunca]], [[Neamț County]], Romania. Evidence indicates that [[Neolithic]] people of the [[Cucuteni-Trypillian culture|Precucuteni Culture]] were boiling the salt-laden spring water through the process of [[briquetage]] to extract the salt as far back as 6050 BC.{{sfn|Weller|Dumitroaia|2005}} The salt extracted from this operation may have had a direct correlation to the rapid growth of this society's population soon after its initial production began.{{sfn|Weller|Brigand|Nuninger|2008|pp=225-230}} The harvest of salt from the surface of [[Xiechi Lake]] near [[Yuncheng, Shanxi|Yuncheng]] in [[Shanxi]], China, dates back to at least 6000 BC, making it one of the oldest verifiable saltworks.{{sfn|Kurlansky|2002|pp=18–19}}

There is more salt in animal tissues such as meat, blood and milk, than there is in plant tissues.<ref name=HMSO/> [[Nomad]]s who subsist on their flocks and herds do not eat salt with their food, but agriculturalists, feeding mainly on cereals and vegetable matter, need to supplement their diet with salt.<ref name="EB">{{cite web |url=http://www.britannica.com/EBchecked/topic/519712/salt-NaCl |title=Salt (NaCl) |last=Wood |first=Frank Osborne |publisher=Encyclopædia Britannica online |accessdate=9 October 2013}}</ref> With the spread of civilization, salt became one of the world's main trading commodities. It was of high value to the ancient Hebrews, the Greeks, the Romans, the Byzantines, the Hittites and other peoples of antiquity. In the Middle East, salt was used to ceremonially seal an agreement, and the ancient Hebrews made a "[[covenant of salt]]" with God and sprinkled salt on their offerings to show their trust in him.<ref>{{cite web |url=http://www.torahclass.com/archived-articles/1036-featured-article-sp-940659465 |title=Covenant of salt |last=Suitt |first=Chris |work=Rediscovering the Old Testament |publisher=Seed of Abraham Ministries |accessdate=12 October 2013}}</ref> An ancient practice in time of war was [[salting the earth]]: scattering salt around in a defeated city in order to prevent plant growth. The [[Bible]] tells the story of King [[Abimelech]] who was ordered by God to do this at [[Shechem]],<ref>{{cite journal |last= Gevirtz |first=Stanley |year=1963 |title=Jericho and Shechem: A Religio-Literary Aspect of City Destruction |journal=Vetus Testamentum |volume=13 |issue=1 |pages=52–62 |jstor=1516752 |doi=10.2307/1516752}}</ref> and various texts claim that the [[Roman Republic|Roman]] general [[Scipio Aemilianus Africanus]] ploughed over and sowed the city of [[Carthage]] with salt after it was defeated in the [[Third Punic War]] (146 BC).<ref>{{cite book |last=Ripley| first=George |last2=Dana |first2=Charles Anderson |title= The New American Cyclopædia: a Popular Dictionary of General Knowledge |volume=4 |page=497 |year= 1863 |url= https://books.google.com/books?id=bK4rAAAAYAAJ&pg=PA497&dq=carthage+sowing+salt&q=carthage+sowing+salt#v=onepage }}</ref>

[[File:Salinas de Maras, Peru-20Sept2013.jpg|thumb|left|Ponds near [[Maras, Peru]], fed from a mineral spring and used for salt production since the time of the [[Inca Empire|Incas]].]]
Salt may have been used for [[barter]] in connection with the [[obsidian]] trade in [[Anatolia]] in the [[Neolithic|Neolithic Era]].<ref>{{cite journal |last1=Golbas |first1=Alper |last2=Basobuyuk |first2=Zeynel |year=2012 |title=The role of salt in the formation of the Anatolian culture |journal=Batman University: Journal of Life Sciences |volume=1 |issue=1 |pages=45–54 |url=http://www.academia.edu/2340259/Anadolu_Kultur_Olusumunda_Tuzun_Rolu-_The_Role_of_Salt_in_the_Formation_of_the_Anatolian_Culture }}</ref> [[Herodotus]] described salt trading routes across Libya back in the 5th century BC. In the early years of the Roman Empire, roads such as the [[Via Salaria]] were built for the transportation of salt from the salt pans of [[Ostia (Rome)|Ostia]] to the capital.<ref>{{cite news |title=A brief history of salt |url=http://content.time.com/time/magazine/article/0,9171,925341,00.html |newspaper=Time Magazine |date=15 March 1982 |accessdate=11 October 2013}}</ref> Salt was included among funeral offerings found in [[ancient Egypt]]ian tombs from the third millennium BC, as were salted birds, and salt fish.{{sfn|Kurlansky|2002|p=38}} From about 2800 BC, the Egyptians began exporting salt fish to the [[Phoenicia]]ns in return for [[Lebanon cedar]], glass and the dye [[Tyrian purple]]; the Phoenicians traded Egyptian salt fish and salt from [[North Africa]] throughout their Mediterranean trade empire.{{sfn|Kurlansky|2002|pp=44}}

In Africa, salt was used as currency south of the Sahara, and slabs of rock salt were used as coins in [[Ethiopia|Abyssinia]].<ref name="EB" /> Moorish merchants in the 6th century traded salt for gold, weight for weight. The [[Tuareg people|Tuareg]] have traditionally maintained routes across the [[Sahara]] especially for the transportation of salt by [[Azalai]] (salt caravans). The caravans still cross the desert from southern Niger to [[Bilma]], although much of the trade now takes place by truck. Each camel takes two bales of [[fodder]] and two of trade goods northwards and returns laden with salt pillars and dates.<ref>{{cite web |url=http://www.bradshawfoundation.com/africa/tuareg_salt_caravans/ |title=Tuareg Salt Caravans of Niger, Africa |last=Paolinelli |first=Franco |publisher=Bradshaw Foundation |accessdate=11 October 2013}}</ref> In Gabon, before the coming of the white man, the coast people carried on a remunerative trade with those of the interior by the medium of sea salt. This was gradually displaced by the salt the white men brought in sacks, so that the coast natives lost their previous profits; as of the author's writing in 1958, sea salt was still the currency best appreciated in the interior.<ref>Schweitzer, Albert. African Notebook. 1958. Indiana University Press.</ref>

[[Salzburg]], [[Hallstatt]], and [[Hallein]] lie within {{convert|17|km|abbr=on}} of each other on the river Salzach in central Austria in an area with extensive salt deposits. [[Salzach]] literally means "salt river" and Salzburg "salt castle", both taking their names from the [[German language|German]] word {{lang|de|''Salz''}} meaning salt and Hallstatt was the site of the world's first [[Salt mining|salt mine]].<ref>{{cite web|url=http://www.virtualvienna.net/columns/billie/hallstatt/hallstatt.html |title=Hallstatt's White Gold: Salt |first=Billie Ann |last=Lopez |work=Virtual Vienna Net |accessdate=3 March 2013 |deadurl=yes |archiveurl=https://web.archive.org/web/20070210142713/http://www.virtualvienna.net/columns/billie/hallstatt/hallstatt.html |archivedate=10 February 2007 }}</ref> The town gave its name to the [[Hallstatt culture]] that began mining for salt in the area in about 800 BC. Around 400 BC, the townsfolk, who had previously used [[pickaxe]]s and [[shovel]]s, began [[open pan salt making]]. During the first millennium BC, Celtic communities grew rich trading salt and [[Salt-cured meat|salted meat]] to [[Ancient Greece]] and [[Ancient Rome]] in exchange for wine and other luxuries.{{sfn|Barber|1999|p=136}}
The word ''[[salary]]'' comes from the [[Latin]] word for salt. The reason for this is unknown; a persistent modern claim that the [[Roman Legion]]s were sometimes paid in salt is baseless.<ref>{{cite web | title=Economics of NaCl: Salt made the world go round | work=Mr Block Archive | author=Bloch, David | url=http://www.salt.org.il/frame_econ.html | accessdate=2006-12-19}}</ref><ref>{{cite web | title=Salt and the evolution of money | author=Bloch, David | url=http://www.salt.org.il/frame_econ.html | work=Mr Block Archive | accessdate=2006-12-19}}</ref><ref>{{cite news | title=The history of salt production at Droitwich Spa | work=BBC | url=http://news.bbc.co.uk/local/herefordandworcester/hi/people_and_places/religion_and_ethics/newsid_8473000/8473037.stm | accessdate=2011-03-28 | date=2010-01-21}}</ref><ref>{{cite web|last1=Gainsford|first1=Peter|title=Salt and salary: were Roman soldiers paid in salt?|url=http://kiwihellenist.blogspot.co.uk/2017/01/salt-and-salary.html|website=Kiwi Hellenist: Modern Myths about the Ancient World|accessdate=11 January 2017}}</ref>
The word ''salad'' literally means "salted", and comes from the ancient Roman practice of salting [[leaf vegetable]]s.{{sfn|Kurlansky|2002|pp=64}}

Wars have been fought over salt. [[Venice]] fought and won a war with [[Genoa]] over the product, and it played an important part in the [[American Revolution]]. Cities on overland trade routes grew rich by levying [[Duty (economics)|duties]],<ref name=Cowen/> and towns like [[Liverpool]] flourished on the export of salt extracted from the salt mines of Cheshire.<ref>{{cite web |url=http://www.igg.org.uk/gansg/12-linind/salt.htm |title=Salt |last=Smith |first=Mike |year=2003 |work=Goods & Not So Goods: Lineside Industries |accessdate=15 October 2013}}</ref> Various governments have at different times imposed salt taxes on their peoples. The voyages of [[Christopher Columbus]] are said to have been financed from salt production in southern Spain, and the oppressive [[Gabelle|salt tax]] in France was one of the causes of the [[French Revolution]]. After being repealed, this tax was reimposed by [[Napoleon]] when he became emperor to pay for his foreign wars, and was not finally abolished until 1945.<ref name=Cowen>{{cite web |url=http://mygeologypage.ucdavis.edu/cowen/~gel115/salt.html |title=The Importance of Salt |last=Cowen |first=Richard |date=1 May 1999 |accessdate=15 October 2013}}</ref> In 1930, [[Mahatma Gandhi]] led at least 100,000 people on the "Dandi March" or "[[Salt Satyagraha]]", in which protesters made their own salt from the sea thus defying [[British rule]] and avoiding paying the [[History of the British salt tax in India|salt tax]]. This [[civil disobedience]] inspired millions of common people, and elevated the [[Indian independence movement]] from an elitist movement to a national struggle.{{sfn|Dalton|1996|p=72}}

==Chemistry==
[[File:Single grain of table salt (electron micrograph).jpg|thumb|[[Scanning electron microscope|SEM]] image of a grain of table salt]]
{{main article|Sodium chloride}}
Salt is mostly [[sodium chloride]], the [[ionic compound]] with the [[chemical formula|formula]] NaCl, representing equal proportions of [[sodium]] and [[chlorine]]. [[Sea salt]] and freshly mined salt (much of which is sea salt from prehistoric seas) also contain small amounts of [[trace element]]s (which in these small amounts are generally good for plant and animal [[health]]). Mined salt is often refined in the production of table salt; it is dissolved in water, purified via [[precipitation (chemistry)|precipitation]] of other minerals out of solution, and re-evaporated. During this same refining process it is often also [[iodised salt|iodized]]. Salt crystals are translucent and cubic in shape; they normally appear white but impurities may give them a blue or purple tinge. The [[molar mass]] of salt is 58.443 g/mol, its melting point is 801&nbsp;°C (1,474&nbsp;°F) and its boiling point 1,465&nbsp;°C (2,669&nbsp;°F). Its density is 2.17 grams per cubic centimetre and it is readily soluble in water. When dissolved in water it separates into Na<sup>+</sup> and Cl<sup>−</sup> ions and the solubility is 359 grams per litre.<ref>{{cite web |url=http://www.britannica.com/EBchecked/topic/519712/salt-NaCl |title=Salt (NaCl) |last1=Wood |first1=Frank Osborne |last2=Ralston |first2=Robert H. |work=Encyclopædia Britannica |accessdate=16 October 2013}}</ref> From cold solutions, salt crystallises as the [[water of hydration|dihydrate]] NaCl·2H<sub>2</sub>O. Solutions of sodium chloride have very different properties from those of pure water; the [[freezing point]] is −21.12&nbsp;°C (−6.02&nbsp;°F) for 23.31&nbsp;wt% of salt, and the [[boiling point]] of saturated salt solution is around 108.7&nbsp;°C (227.7&nbsp;°F).<ref name=u1>Elvers, B. ''et al.'' (ed.) (1991) Ullmann's Encyclopedia of Industrial Chemistry, 5th ed. Vol. A24, Wiley, p. 319, ISBN 978-3-527-20124-2.</ref>

==Edible salt==
{{redirect|Table salt|specific edible salts|List of edible salts}}
[[File:Salt shaker on white background.jpg|thumb|Salt shaker]]
Salt is essential to the health of humans and other animals, and is one of the [[Basic tastes#Basic tastes|five basic taste sensations]].<ref>{{cite web |url=http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/T/Taste.html |title=The sense of taste |date=16 March 2013 |accessdate=16 October 2013}}</ref>

Salt is used in many cuisines around the world, and is often found in [[salt shaker]]s on diners' eating tables for their personal use on food. Salt is also an ingredient in many manufactured foodstuffs. Table salt is a refined salt containing about 97 to 99&nbsp;percent [[sodium chloride]].<ref>{{cite web|title=Tesco Table Salt 750g|url=http://www.tesco.com/superstore/xpi/8/xpi50042778.htm|publisher=Tesco|accessdate=5 December 2010|quote=Nutritional analysis provided with Tesco Table Salt states 38.9&nbsp;percent sodium by weight which equals 97.3&nbsp;percent sodium chloride}}</ref><ref>[http://www.wasalt.com.au/Table.html Table Salt]. Wasalt.com.au. Retrieved 7 July 2011.</ref><ref>[http://www.codexalimentarius.net/download/standards/3/CXS_150e.pdf The international Codex Alimentarius Standard for Food Grade Salt]. (PDF). Retrieved 7 July 2011.</ref> Usually, [[anticaking agents]] such as [[sodium aluminosilicate]] or [[magnesium carbonate]] are added to make it free-flowing. [[Iodized salt]], containing [[potassium iodide]], is widely available. Some people put a [[desiccant]], such as a few grains of uncooked [[rice]]<ref>{{cite web |url= http://www.newton.dep.anl.gov/askasci/gen01/gen01420.htm |title= Rice in Salt Shakers |publisher= Ask a Scientist |accessdate=29 July 2008}}</ref> or a [[saltine cracker]], in their salt shakers to absorb extra moisture and help break up salt clumps that may otherwise form.<ref>{{cite web |url=http://ww3.komotv.com/story/1454284/food-freshness?redirected=true |archiveurl=https://web.archive.org/web/20110820105950/http://ww3.komotv.com/story/1454284/food-freshness?redirected=true |archivedate=20 August 2011|title= Food Freshness |publisher= KOMO News |accessdate=8 July 2011}}</ref>

===Fortified table salt===
Some table salt sold for consumption contain additives which address a variety of health concerns, especially in the developing world. The identities and amounts of additives vary widely from country to country. [[Iodine]] is an important micronutrient for humans, and a [[iodine deficiency|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.{{sfn|Vaidya|Chakera|Pearce|2011}} Iodized salt has been used to correct these conditions since 1924{{sfn|Markel|1987}} and consists of table salt mixed with a minute amount of [[potassium iodide]], [[sodium iodide]] or [[sodium iodate]]. A small amount of [[dextrose]] may also be added to stabilize the iodine.<ref>{{cite web |url=http://extension.psu.edu/food-safety/food-preservation/faq/canning-and-pickling-salt |title=Canning and Pickling salt |publisher=Penn State University}}; {{cite web|url=http://www.mortonsalt.com/faqs/food-salt-faqs|publisher = Morton Salt |title=FAQs}}</ref> Iodine deficiency affects about two billion people around the world and is the leading preventable cause of [[mental retardation]].<ref name="mcneil">{{cite news|url=https://www.nytimes.com/2006/12/16/health/16iodine.html |title=In Raising the World's I.Q., the Secret's in the Salt|last=McNeil|first=Donald G. Jr|date=16 December 2006|work=[[The New York Times]]|accessdate=4 December 2008}}</ref> Iodized table salt has significantly reduced disorders of iodine deficiency in countries where it is used.<ref>{{cite web|title=Iodized salt|url=http://www.saltinstitute.org/Uses-benefits/Salt-in-Food/Essential-nutrient/Iodized-salt|publisher=Salt Institute|accessdate=5 December 2010|year=2009}}</ref>

The amount of iodine and the specific iodine compound added to salt varies from country to country. In the [[United States]], the [[Food and Drug Administration]] (FDA) recommends [21 CFR 101.9 (c)(8)(iv)] 150 [[micrograms]] of iodine per day for both men and women. US iodized salt contains 46–77 ppm (parts per million), whereas in the UK the iodine content of iodized salt is recommended to be 10–22 ppm.<ref>{{cite web|title=Discussion Paper on the setting of maximum and minimum amounts for vitamins and minerals in foodstuffs|url=http://ec.europa.eu/food/food/labellingnutrition/supplements/documents/akj_en.pdf|publisher=Directorate-General Health & Consumers |accessdate=5 December 2010}}</ref>

[[Sodium ferrocyanide]], also known as yellow [[prussiate]] of soda, is sometimes added to salt as an anticaking agent. The additive is considered safe for human consumption.<ref name="hansard.millbanksystems.com"/>{{sfn|European Commission|2001|p=3}} Such anti-caking agents have been added since at least 1911 when magnesium carbonate was first added to salt to make it flow more freely.<ref>{{cite web |title=Morton Salt FAQ |url=http://www.mortonsalt.com/faqs/general-company-faqs#q3 |accessdate =12 May 2007}}</ref> The safety of sodium ferrocyanide as a food additive was found to be provisionally acceptable by the [[Committee on Toxicity]] in 1988.<ref name="hansard.millbanksystems.com">[http://hansard.millbanksystems.com/written_answers/1993/may/05/table-salt Discussions of the safety of sodium hexaferrocyanate in table salt]. Hansard.millbanksystems.com (5 May 1993). Retrieved 7 July 2011.</ref> Other anticaking agents sometimes used include [[tricalcium phosphate]], [[calcium carbonate|calcium]] or magnesium carbonates, [[fatty acid]] salts ([[acid salt]]s), [[magnesium oxide]], [[silicon dioxide]], [[calcium silicate]], sodium aluminosilicate and [[calcium aluminosilicate]]. Both the European Union and the United States Food and Drug Administration permitted the use of [[aluminium]] in the latter two compounds.<ref>{{cite web | first1=Wilella Daniels | last1=Burgess | first2=April C. | last2=Mason | url=http://www.ces.purdue.edu/extmedia/HE/HE-625.html | title=What Are All Those Chemicals in My Food? | publisher=School of Consumer and Family Sciences, Purdue University | accessdate=27 February 2011}}</ref>

In "doubly fortified salt", both iodide and iron salts are added. The latter alleviates [[iron deficiency anaemia]], which interferes with the mental development of an estimated 40% of infants in the developing world. A typical iron source is [[Iron(II) fumarate|ferrous fumarate]].{{sfn|Westphal|Kristen|Wegener|Ambatiello|2010}} Another additive, especially important for [[pregnancy|pregnant]] women, is [[folic acid]] (vitamin B<sub>9</sub>), which gives the table salt a yellow color. Folic acid helps prevent [[neural tube defect]]s and anaemia, which affect young mothers, especially in developing countries.{{sfn|Westphal|Kristen|Wegener|Ambatiello|2010}}

A lack of [[fluorine]] in the diet is the cause of a greatly increased incidence of [[dental caries]].{{sfn|Selwitz|Ismail|Pitts|2007}} [[Fluoride]] salts can be added to table salt with the goal of reducing tooth decay, especially in countries that have not benefited from fluoridated toothpastes and fluoridated water. The practice is more common in some European countries where [[water fluoridation]] is not carried out. In [[France]], 35% of the table salt sold contains added [[sodium fluoride]].{{sfn|Westphal|Kristen|Wegener|Ambatiello|2010}}

===Other kinds===
[[File:Sea Salt.jpg|thumb|left|Irregular crystals of [[sea salt]]]]
Unrefined [[sea salt]] contains small amounts of [[magnesium]] and [[calcium]] [[halides]] and [[sulfate]]s, traces of [[algae|algal products]], salt-resistant bacteria and sediment particles. The calcium and magnesium salts confer a faintly bitter overtone, and they make unrefined sea salt [[hygroscopic]] (i.e., it gradually absorbs moisture from air if stored uncovered). Algal products contribute a mildly "fishy" or "sea-air" odour, the latter from [[Organobromine compound#Organobromine compounds in nature|organobromine compounds]]. Sediments, the proportion of which varies with the source, give the salt a dull grey appearance. Since taste and aroma compounds are often detectable by humans in minute concentrations, sea salt may have a more complex flavor than pure sodium chloride when sprinkled on top of food. When salt is added during cooking however, these flavors would likely be overwhelmed by those of the food ingredients.{{sfn|McGee|2004|p=642}} The refined salt industry cites scientific studies saying that raw sea and rock salts do not contain enough [[iodine]] salts to prevent [[Iodine deficiency|iodine deficiency diseases]].<ref>{{cite web|title=References on food salt & health issues|url=http://www.saltinstitute.org/Articles-references/References-on-salt-issues/References-on-salt-issues/References-on-food-salt-health-issues|publisher=Salt Institute|accessdate=5 December 2010|year=2009}}</ref>

Different natural salts have different [[Minerality#I–P|mineralities]] depending on their source, giving each one a unique flavour. [[Fleur de sel]], a natural sea salt from the surface of evaporating brine in salt pans, has a unique flavour varying with the region from which it is produced. In traditional [[Korean cuisine]], so-called "[[Jukyeom|bamboo salt]]" is prepared by roasting salt{{sfn|Livingston|2005|p=45}} in a [[bamboo]] container plugged with mud at both ends. This product absorbs minerals from the bamboo and the mud, and has been claimed to increase the [[clastogen|anticlastogenic]] and [[mutagen|antimutagenic]] properties of [[doenjang]] (a fermented bean paste).{{sfn|Shahidi|Shi|Ho|2005|p=575}}

[[Kosher salt]], though refined, contains no iodine and has a much larger grain size than most refined salts. This can give it different properties when used in cooking, and can be useful for preparing [[kosher meat]]. Some kosher salt has been certified to meet [[kosher]] requirements by a [[hechsher]], but this is not true for all products labelled as kosher salt.<ref>{{cite web |url=http://www.saltworks.us/salt_info/kosher-salt.asp |title=Kosher Salt Guide |publisher=SaltWorks |year=2010}}</ref>

[[Pickling salt]] is ultrafine to speed dissolving to make [[brine]]. Gourmet salts may be used for specific tastes.

===Salt in food===
Salt is present in most [[food]]s, but in naturally occurring foodstuffs such as meats, vegetables and fruit, it is present in very small quantities. It is often added to processed foods (such as [[canning|canned foods]] and especially [[salting (food)|salted foods]], [[pickling|pickled foods]], and [[snack food]]s or other [[convenience food]]s), where it functions as both a [[preservative]] and a [[flavor]]ing. [[Dairy salt]] is used in the preparation of butter and cheese products.<ref>{{cite book |last=Pieters |first=A. J. |last2=Flint |first2=D. |last3=Garriott |first3=E. B. |last4=Wickson |first4=E. J. |last5=Lamson-Scribner |first5=F. |last6=Brackett |first6=G. B. |last7=Atwater |first7=H. W. |last8=Alvord |first8=H. E. |last9=Withcombe |first9=J. |last10=Howard |first10=L. O. |title=Experiment Station Work |publisher=[[United States Department of Agriculture|U.S. Department of Agriculture]] |series=Bread and the Principles of Bread Making |year=1899 |url=https://books.google.com/books?id=l85CAQAAMAAJ&pg=RA5-PA28 |accessdate=November 17, 2015 |pages=28–30}}</ref> Before the advent of electrically powered [[refrigeration]], salting was one of the main methods of [[food preservation]]. Thus, [[herring]] contains 67&nbsp;mg sodium per 100&nbsp;g, while [[kipper]], its preserved form, contains 990&nbsp;mg. Similarly, [[pork]] typically contains 63&nbsp;mg while [[bacon]] contains 1,480&nbsp;mg, and [[potato]]es contain 7&nbsp;mg but [[potato crisp]]s 800&nbsp;mg per 100 g.<ref name=HMSO /> The main sources of salt in the diet, apart from direct use of sodium chloride, are bread and cereal products, meat products and milk and dairy products.<ref name=HMSO>{{cite book |title=Manual of Nutrition |last=Buss |first=David |last2=Robertson |first2=Jean |year=1973 |publisher=Her Majesty's Stationery Office |isbn=0112411126 |pages=37–38}}</ref>

In many East Asian cultures, salt is not traditionally used as a condiment.<ref>{{cite web |url=http://community.seattletimes.nwsource.com/archive/?date=20010729&slug=pfish29 |work=The Seattle Times |title=The Salt of Southeast Asia |accessdate=7 July 2011 |year=2001}}</ref> In its place, condiments such as [[soy sauce]], [[fish sauce]] and [[oyster sauce]] tend to have a high sodium content and fill a similar role to table salt in western cultures. They are most often used for cooking rather than as table condiments.<ref>{{cite web |url=http://www.diet.com/g/asian-diet |title=Asian diet |publisher=Diet.com |accessdate=7 July 2013}}</ref>

===Sodium consumption and health===
{{Main article|Health effects of salt}}

Table salt is made up of just under 40% sodium by weight, so a 6{{nbsp}}g serving (1{{nbsp}}teaspoon) contains about 2,300{{nbsp}}mg of sodium.<ref name="USDA">{{cite web | url=http://ndb.nal.usda.gov/ndb/foods/show/277 | title=National Nutrient Database for Standard Reference, Basic Report: 02047, Salt, table | publisher=[[United States Department of Agriculture]] | work=Agricultural Research Service, National Nutrient Database for Standard Reference, Release 27 | accessdate=8 January 2015}}</ref> Sodium serves a vital purpose in the human body: via its role as an electrolyte, it helps nerves and muscles to function correctly, and it is one factor involved in the [[autoregulation|osmotic regulation]] of water content in body organs ([[fluid balance]]).<ref>{{cite web |url=https://www.nlm.nih.gov/medlineplus/dietarysodium.html |title=Dietary sodium |publisher=MedLinePlus |accessdate=17 October 2013}}</ref> Most of the sodium in the [[Western diet]] comes from salt.<ref name=CDC>{{cite web |url=http://www.cdc.gov/salt/ |title=Most Americans should consume less sodium |work=Salt |publisher=Centers for Disease Control and Prevention |accessdate=17 October 2013}}</ref> The habitual salt intake in many Western countries is about 10 g per day, and it is higher than that in many countries in Eastern Europe and Asia.<ref name=Strazzullo/> The high level of sodium in many processed foods has a major impact on the total amount consumed.<ref>{{cite web |url=https://www.nice.org.uk/guidance/ph25/resources/guidance-prevention-of-cardiovascular-disease-pdf |title=Prevention of cardiovascular disease |date=1 June 2010 |publisher=National Institute for Health and Clinical Excellence |accessdate=5 May 2015}}</ref> 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.<ref>{{cite web |url=http://www.cdc.gov/salt/food.htm |title=Sodium and food sources |work=Salt |publisher=Centers for Disease Control and Prevention |accessdate=17 October 2013}}</ref>

Because consuming too much sodium increases risk of [[cardiovascular disease]]s,<ref name=CDC/> health organizations generally recommend that people reduce their dietary intake of salt.<ref name=CDC/><ref name=WHO2013/><ref name=He2013/><ref name="aha">{{cite web | url=http://www.heart.org/HEARTORG/HealthyLiving/HealthyEating/Nutrition/Sodium-and-Salt_UCM_303290_Article.jsp#.V1jHedQrJkg | title=Sodium and salt | publisher=American Heart Association | date=2016 | accessdate=8 June 2016}}</ref> High sodium intake is associated with a greater risk of [[stroke]], total cardiovascular disease and [[kidney disease]].<ref name=IOM2013/><ref name=Strazzullo>{{cite journal |last1= Strazzullo |first1=Pasquale |last2=D'Elia |first2=Lanfranco |last3=Kandala |first3=Ngianga-Bakwin |last4=Cappuccio |first4=Francesco P. |year=2009 |title=Salt intake, stroke, and cardiovascular disease: meta-analysis of prospective studies |journal=British Medical Journal |volume=339 |issue=b4567 |pages=b4567 |doi=10.1136/bmj.b4567 |pmc=2782060 |pmid=19934192}}</ref> A reduction in sodium intake by 1,000&nbsp;mg per day may reduce cardiovascular disease by about 30 percent.<ref name=USDA2015>{{cite book|title=Scientific Report of the 2015 Dietary Guidelines Advisory Committee|date=2015|publisher=US Department of Agriculture|page=7|url=http://www.health.gov/dietaryguidelines/2015-scientific-report/PDFs/Scientific-Report-of-the-2015-Dietary-Guidelines-Advisory-Committee.pdf}}</ref><ref name=CDC/> In adults and children with no acute illness, a decrease in the intake of sodium from the typical high levels reduces blood pressure.<ref name=He2013>{{cite journal|last1=He|first1=F. J.|last2=Li |first2=J. |last3=Macgregor |first3=G. A. |title=Effect of longer term modest salt reduction on blood pressure: Cochrane systematic review and meta-analysis of randomised trials.|journal=BMJ (Clinical research ed.)|date=3 April 2013|volume=346|pages=f1325|pmid=23558162|doi=10.1136/bmj.f1325}}</ref><ref name=Abur2013>{{cite journal |last1=Aburto |first1=Nancy J. |last2=Ziolkovska |first2=Anna |last3=Hooper |first3=Lee |last4=Elliott |first4=Paul |last5=Cappuccio |first5=Francesco P. |last6=Meerpohl |first6=Joerg J. |display-authors=3 |year=2013 |title=Effect of lower sodium intake on health: systematic review and meta-analyses |journal=British Medical Journal |volume=346 |issue=f1326 |pages=f1326 |doi=10.1136/bmj.f1326 |pmid=23558163 |pmc=4816261}}</ref> A low sodium diet results in a greater improvement in blood pressure in people with [[hypertension]].<ref name=Gra2011>{{cite journal|last1=Graudal|first1=N. A.|last2=Hubeck-Graudal |first2=T. |last3=Jurgens |first3=G. |title=Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride.|journal=The Cochrane database of systematic reviews|date=9 November 2011|issue=11|pages=CD004022|pmid=22071811|doi=10.1002/14651858.CD004022.pub3}}</ref><ref>{{cite journal|last1=Adler|first1=A. J.|last2=Taylor|first2=F.|last3=Martin|first3=N.|last4=Gottlieb|first4=S.|last5=Taylor|first5=R. S.|last6=Ebrahim|first6=S.|title=Reduced dietary salt for the prevention of cardiovascular disease|journal=The Cochrane database of systematic reviews|date=18 December 2014|volume=12|issue=12|pages=CD009217|pmid=25519688|doi=10.1002/14651858.CD009217.pub3}}</ref>

The [[World Health Organization]] recommends that adults should consume less than 2,000&nbsp;mg of sodium (which is contained in 5{{nbsp}}g of salt) per day.<ref name=WHO2013>{{cite web |url=http://www.who.int/mediacentre/news/notes/2013/salt_potassium_20130131/en/ |title=WHO issues new guidance on dietary salt and potassium |date=31 January 2013 |publisher=World Health Organization |accessdate=17 October 2013}}</ref> Guidelines by the United States recommend that people with hypertension, African Americans, and middle-aged and older adults should limit consumption to no more than 1,500&nbsp;mg of sodium per day and meet the potassium recommendation of 4,700&nbsp;mg/day with a healthy diet of fruits and vegetables.<ref name=CDC/><ref name=Health.gov2010>{{cite book|title=Dietary Guidelines for Americans, 2010|date=2010|publisher=U.S. Department of Agriculture and the U.S. Department of Health and Human Services|page=24|url=http://www.health.gov/dietaryguidelines/dga2010/DietaryGuidelines2010.pdf|accessdate=April 29, 2015|quote=African Americans, individuals with hypertension, diabetes, or chronic kidney disease and individuals ages 51 and older, comprise about half of the U.S. population ages 2 and older. While nearly everyone benefits from reducing their sodium intake, the blood pressure of these individuals tends to be even more responsive to the blood pressure-raising effects of sodium than others; therefore, they should reduce their intake to 1,500 mg per day.}}</ref>

While reduction of sodium intake to less than 2,300&nbsp;mg per day is recommended by developed countries,<ref name=CDC/> one review recommended that sodium intake be reduced to at least 1,200&nbsp;mg (contained in 3{{nbsp}}g of salt) per day, as a further reduction in salt intake the greater the fall in systolic blood pressure for all age groups and ethinicities.<ref name=He2013/> Another review indicated that there is inconsistent/insufficient evidence to conclude that reducing sodium intake to lower than 2,300&nbsp;mg per day is either beneficial or harmful.<ref>{{Cite book|url=https://www.nap.edu/read/18311/chapter/7#122|title=5 Findings and Conclusions {{!}} Sodium Intake in Populations: Assessment of Evidence {{!}} The National Academies Press|language=en|doi=10.17226/18311}}</ref>

One of the two most prominent dietary risks for disability in the world is eating too much sodium.<ref>{{Cite journal|last=Lim|first=Stephen S.|last2=Vos|first2=Theo|last3=Flaxman|first3=Abraham D.|last4=Danaei|first4=Goodarz|last5=Shibuya|first5=Kenji|last6=Adair-Rohani|first6=Heather|last7=Amann|first7=Markus|last8=Anderson|first8=H. Ross|last9=Andrews|first9=Kathryn G.|date=2012-12-15|title=A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010|journal=Lancet (London, England)|volume=380|issue=9859|pages=2224–2260|doi=10.1016/S0140-6736(12)61766-8|pmc=4156511|pmid=23245609}}</ref>

==Non-dietary uses==
{{Main article|Sodium chloride}}

Only about 6% of the salt manufactured in the world is used in food. Of the remainder, 12% is used in water conditioning processes, 8% goes for de-icing highways and 6% is used in agriculture. The rest (68%) is used for manufacturing and other industrial processes,<ref>{{cite web |url=http://www.maldonsalt.co.uk/About-Salt-The-many-uses-of-Salt.html |title=The many uses of salt |publisher=Maldon Salt Company |accessdate=10 October 2013}}</ref> and sodium chloride is one of the largest inorganic raw materials used by volume. Its major chemical products are [[caustic soda]] and [[chlorine]], which are separated by the [[electrolysis]] of a pure brine solution. These are used in the manufacture of [[PVC]], [[plastic]]s, [[paper pulp]] and many other inorganic and organic compounds. Salt is also used as a [[Flux (metallurgy)|flux]] in the production of [[aluminium]]. For this purpose, a layer of melted salt floats on top of the molten metal and removes iron and other metal contaminants. It is also used in the manufacture of [[soap]]s and [[glycerine]], where it is added to the vat to precipitate out the [[Saponification|saponified]] products. As an emulsifier, salt is used in the manufacture of [[synthetic rubber]], and another use is in the firing of [[pottery]], when salt added to the furnace vaporises before condensing onto the surface of the ceramic material, forming a strong [[Ceramic glaze|glaze]].<ref name=WASG>{{cite web |url=http://www.wasalt.com.au/SaltUses.html |title=Salt uses |publisher=WA Salt Group |accessdate=10 October 2013 |archiveurl= https://web.archive.org/web/20131011054052/http://www.wasalt.com.au/SaltUses.html |archivedate= 2013-10-11 }}</ref>

When drilling through loose materials such as sand or gravel, salt may be added to the [[drilling fluid]] to provide a stable "wall" to prevent the hole collapsing. There are many other processes in which salt is involved. These include its use as a [[mordant]] in [[textile]] dying, to regenerate [[resin]]s in water softening, for the [[Tanning (leather)|tanning]] of hides, the preservation of meat and fish and the [[canning]] of meat and vegetables.<ref name=WASG/><ref name=IHS>{{cite web |url=http://www.ihs.com/products/chemical/planning/ceh/sodium-chloride.aspx |title=Sodium chloride |date=1 December 2008 |publisher=IHS Chemical |accessdate=12 March 2013}}</ref>{{sfn|Kostick|2011}}

==Production==
{{contradict|date=April 2017}}
{{See also|List of countries by salt production}}

Food grade salt accounts for only a small part of salt production in [[Developed country|industrialized countries]] (7% in Europe),<ref>{{cite web | url=http://eusalt.com/salt-uses | title=Salt Uses | publisher=European Salt Producers' Association | accessdate=5 May 2015}}</ref> although worldwide, food uses account for 17.5% of total production.<ref>{{cite web | url=http://www.roskill.com/reports/salt | title=Roskill Information Services | publisher=Roskill.com | date=30 March 2011 | accessdate=7 July 2011}}</ref>

In 2013, total world production of salt was 264 million [[tonne]]s, the top five producers being China (71 million), the United States (40 million), India (18 million), Germany (12 million) and Canada (11 million).<ref>{{cite web | url=http://minerals.usgs.gov/minerals/pubs/commodity/salt/mcs-2014-salt.pdf | title=Salt | publisher=US Geological Survey, Mineral Commodity Summaries | date=February 2014 | accessdate=8 June 2016}}</ref>

{{multiple image|total_width=300|direction=vertical
| image1 = Bo Kluea 01.jpg
| width1 = 2500
| height1 = 1737
| caption1 = [[Brine]] from [[salt wells]] is boiled to produce salt at [[Bo Kluea District|Bo Kluea]], [[Nan Province]], Thailand

| image2 = Piles of Salt Salar de Uyuni Bolivia Luca Galuzzi 2006 a.jpg
| width2 = 2000
| height2 = 1320
| caption2 = Salt mounds in [[Salar de Uyuni]], Bolivia
}}
The manufacture of salt is one of the oldest chemical industries.<ref>{{cite web | url=http://www.salt.org.il/arch.html | title=Salt made the world go round | work=Salt.org.il | date=1 September 1997 | accessdate=7 July 2011}}</ref> A major source of salt is seawater, which has a [[salinity]] of approximately 3.5%. This means that there are about {{convert|35|g|oz}} of [[sea salt|dissolved salts]], predominantly [[sodium]] ({{chem|Na||+}}) and [[chloride]] ({{chem|Cl||-}}) [[ions]], per kilogram (2.2&nbsp;lbs) of water.{{sfn|Millero|Feistel|Wright|McDougall|2008}} The world's oceans are a virtually inexhaustible source of salt, and this abundance of supply means that reserves have not been calculated.<ref name=IHS/> The evaporation of seawater is the production method of choice in marine countries with high evaporation and low precipitation rates. [[Salt evaporation pond]]s are filled from the ocean and salt crystals can be harvested as the water dries up. Sometimes these ponds have vivid colours, as some species of algae and other micro-organisms thrive in conditions of high salinity.<ref>{{cite web | url = http://visibleearth.nasa.gov/view.php?id=2631 | title = Salt Ponds, South San Francisco Bay |work= NASA Visible Earth |publisher=NASA |accessdate=5 May 2015}}</ref>

Elsewhere, salt is extracted from the vast sedimentary deposits which have been laid down over the millennia from the evaporation of seas and lakes. These are either [[salt mine|mined]] directly, producing rock salt, or are extracted in solution by pumping water into the deposit. In either case, the salt may be purified by mechanical evaporation of brine. Traditionally, this was done in [[Open pan salt making|shallow open pans]] which were heated to increase the rate of evaporation. More recently, the process is performed in pans under [[vacuum]].{{sfn|Kostick|2011}} The raw salt is refined to purify it and improve its storage and handling characteristics. This usually involves recrystallization during which a brine solution is treated with chemicals that precipitate most impurities (largely magnesium and calcium salts). Multiple stages of evaporation are then used to collect pure sodium chloride crystals, which are [[kiln]]-dried.<ref>[http://web.archive.org/web/20090409144219/http://www.saltsense.co.uk/aboutsalt-prod02.htm About salt: Production]. The Salt Manufacturers Association</ref> Some salt is produced using the [[Alberger process]], which involves vacuum pan evaporation combined with the seeding of the solution with cubic crystals, and produces a grainy-type flake.<ref>{{cite web |url=http://www.britannica.com/EBchecked/topic/12642/Alberger-process |title=Alberger process |work=Manufacture of salt: Uses of artificial heat |publisher=Encyclopædia Britannica online |accessdate=9 October 2013}}</ref> The [[Ayoreo people|Ayoreo]], an indigenous group from the Paraguayan [[Gran Chaco people|Chaco]], obtain their salt from the ash produced by burning the timber of the Indian salt tree (''Maytenus vitis-idaea'') and other trees.{{sfn|Schmeda-Hirschmann|1994}}

One of the largest [[salt mining]] operations in the world is at the [[Khewra Salt Mine]] in Pakistan. The mine has nineteen storeys, eleven of which are underground, and {{convert|400|km|abbr=on}} 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. Extraction of [[Himalayan salt]] is expected to last 350 years at the present rate of extraction of around 385,000 tons per annum.<ref name="The Seattle Times">{{cite news |last=Pennington |first=Matthew |title=Pakistan salt mined old-fashioned way mine|url=http://seattletimes.nwsource.com/html/nationworld/2002159747_saltmine25.html |accessdate=11 October 2013 |newspaper=The Seattle Times |date=25 January 2005}}</ref>

==In religion==
[[File:Russian bread and salt.jpg|thumb|[[Bread and salt]] at a Russian wedding ceremony]]
Salt has long held an important place in religion and culture. At the time of [[Historical Vedic religion|Brahmanic]] sacrifices, in [[Hittites|Hittite]] rituals and during festivals held by [[Semitic people|Semites]] and Greeks at the time of the [[new moon]], salt was thrown into a fire where it produced crackling noises.<ref>{{cite web |url=http://www.bookrags.com/research/salt-eorl-12/ |title=Research article: Salt |work=Encyclopedia of Religion |accessdate=13 October 2013}}</ref> The ancient Egyptians, Greeks and Romans invoked their gods with offerings of salt and water and some people think this to be the origin of [[Holy Water]] in the Christian faith.<ref name="ReferenceA"/> In [[Aztec]] mythology, [[Huixtocihuatl]] was a fertility goddess who presided over salt and salt water.<ref>{{cite web |url=http://www.amoxtli.org/cuezali/festivals.html |title=The Aztec Festivals: Toxcatl (Dryness) |last=Quipoloa |first=J. |year=2007 |work=The Aztec Gateway |accessdate=18 March 2013}}</ref>

Salt is considered to be a very auspicious substance in [[Hinduism]] and is used in particular religious ceremonies like house-warmings and weddings.<ref name=Gray>{{cite news |title=What Lies Beneath |last=Gray |first=Steven |url=http://www.time.com/time/magazine/article/0,9171,2001007,00.html |newspaper=Time Magazine |date=7 December 2010 |accessdate=13 March 2013}}</ref> In [[Jainism]], devotees lay an offering of raw rice with a pinch of salt before a deity to signify their devotion and salt is sprinkled on a person's cremated remains before the ashes are buried.<ref>{{cite web |url=http://www.finaljourneyseminars.com/?page_id=472 |title=The Final Journey: What to do when your loved one passes away |accessdate=12 March 2013}}</ref> Salt is believed to ward off evil spirits in [[Mahayana Buddhism|Mahayana Buddhist]] tradition, and 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.<ref>{{cite web |url=http://www.cargill.com/salt/about/historyofsalt/religion/ |title=Religion: Chasing away evil spirits |work=History of salt |publisher=Cagill |accessdate=13 October 2013}}</ref> In [[Shinto]], salt is used for [[ritual purification]] of locations and people ([[harae]], specifically shubatsu), and small piles of salt are placed in dishes by the entrance of establishments for the two-fold purposes of warding off evil and attracting patrons.<ref>[http://japanesereligions.blogspot.com/2009/03/can-you-pass-salt-please.html Can you pass the salt, please?], Robert Camara, 30 March 2009</ref>

In the [[Hebrew Bible]], there are thirty-five verses which [[Salt in the Bible|mention salt]].<ref name=BLB>{{cite web |url=http://www.blueletterbible.org/search/translationResults.cfm?Criteria=salt&t=KJV |title=Dictionary and Word Search for '"salt"' in the KJV |date=1996–2013 |work=Blue Letter Bible |publisher= Sowing Circle |accessdate=13 March 2013}}</ref> One of these mentions [[Lot's wife]], who was turned into a pillar of salt when she looked back at the cities of [[Sodom and Gomorrah]] ([[Book of Genesis|Genesis]] 19:26) as they were destroyed. When the judge [[Abimelech (Judges)|Abimelech]] destroyed the city of [[Shechem]], he is said to have "[[salting the earth|sown salt]] on it," probably as a curse on anyone who would re-inhabit it (Judges 9:45). The [[Book of Job]] contains the first mention of salt as a condiment. "Can that which is unsavoury be eaten without salt? or is there any taste in the white of an egg?" (Job 6:6).<ref name=BLB/> In the [[New Testament]], six verses mention salt. In the [[Sermon on the Mount]], [[Jesus]] referred to his followers as the "[[Salt and Light|salt of the earth]]". [[Paul the Apostle|The apostle Paul]] also encouraged Christians to "let your conversation be always full of grace, seasoned with salt" (Colossians 4:6).<ref name=BLB/> Salt is mandatory in the rite of the [[Tridentine Mass]].<ref name=CE>[[Wikisource:Catholic Encyclopedia (1913)/Salt]]</ref> Salt is used in the third item (which includes an [[Exorcism]]) of the Celtic Consecration (''cf.'' [[Gallican Rite]]) that is employed in the consecration of a church. Salt may be added to the water "where it is customary" in the Roman Catholic rite of Holy water.<ref name=CE/>

In [[Judaism]], it is recommended to have either a salty bread or to add salt to the bread if this bread is unsalted when doing [[Kiddush]] for [[Shabbat]]. It is customary to spread some salt over the bread or to dip the bread in a little salt when passing the bread around the table after the Kiddush.<ref>Naftali Silberberg [http://www.chabad.org/library/article_cdo/aid/484194/jewish/Why-dip-in-salt.htm Why is the Challah dipped in salt before it is eaten?], Chabad.org</ref> To preserve the covenant between their people and God, Jews dip the [[Sabbath]] bread in salt.<ref name="ReferenceA">{{cite journal|title=10+1 Things you may not know about Salt |journal=Epikouria |year=2006 |volume=Fall/Winter |issue=3 |url=http://www.epikouria.com/issue3/article6-things.php |deadurl=yes |archiveurl=https://web.archive.org/web/20080704055740/http://www.epikouria.com/issue3/article6-things.php |archivedate=4 July 2008 }}</ref>

In [[Wicca]], salt is symbolic of the element Earth. It is also believed to cleanse an area of harmful or negative energies. A dish of salt and a dish of water are almost always present on an [[altar]], and salt is used in a wide variety of rituals and ceremonies.<ref>{{cite book |title=Wicca: A Guide for the Solitary Practitioner |last=Cunningham |first=Scott |year=1989 |publisher=Llewellyn Worldwide |isbn=9780875421186 |pages=60, 63, 104, 113|url=https://books.google.com/?id=U3un43fTEOcC&pg=PR9&dq=Wicca+salt#v=onepage&q=Wicca%20salt&f=false }}</ref>

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* {{Cite journal | last1 = Caldwell | first1 = J. H. | last2 = Schaller | first2 = K. L. | last3 = Lasher | first3 = R. S. | last4 = Peles | first4 = E. | last5 = Levinson | first5 = S. R. | title = Sodium channel Nav1.6 is localized at nodes of Ranvier, dendrites, and synapses | doi = 10.1073/pnas.090034797 | journal = Proceedings of the National Academy of Sciences | volume = 97 | issue = 10 | pages = 5616–20 | year = 2000 | pmid = 10779552| pmc = 25877| ref=harv}} <!-- {{sfn|Caldwell|Schaller|Lasher|Peles|2000}} -->
* {{Cite journal | last1 = Dumler | first1 = F. | title = Dietary Sodium Intake and Arterial Blood Pressure | doi = 10.1053/j.jrn.2008.10.006 | journal = Journal of Renal Nutrition | volume = 19 | issue = 1 | pages = 57–60 | year = 2009 | pmid = 19121772| pmc = | ref=harv}} <!-- {{sfn|Dumler|2009}} -->
* {{Cite book | last1 = Feldman | first1 = S. R. | chapter = Sodium Chloride | doi = 10.1002/0471238961.1915040902051820.a01.pub2 | title = Kirk-Othmer Encyclopedia of Chemical Technology | year = 2005 | isbn = 0471238961 | pmid = | pmc = | ref=harv}} <!-- {{sfn|Feldman|2005}} -->
* {{Cite web |last=Kostick |first=Dennis S. |url=http://minerals.usgs.gov/minerals/pubs/commodity/salt/myb1-2010-salt.pdf |title=Salt |date=1 November 2011 |work=2010 Minerals Yearbook |publisher=U.S. Geological Survey |accessdate=12 March 2013 |ref=harv}}
* {{Cite journal | last1 = Markel | first1 = H. | title = "When it rains it pours": Endemic goiter, iodized salt, and David Murray Cowie, MD | doi = 10.2105/AJPH.77.2.219 | journal = American Journal of Public Health | volume = 77 | issue = 2 | pages = 219–229 | year = 1987 | pmid = 3541654| pmc =1646845 | ref=harv}} <!-- {{sfn|Markel|1987}} -->
* {{Cite journal | last1 = McCarron | first1 = D. A. | last2 = Geerling | first2 = J. C. | last3 = Kazaks | first3 = A. G. | last4 = Stern | first4 = J. S. | title = Can Dietary Sodium Intake Be Modified by Public Policy? | doi = 10.2215/CJN.04660709 | journal = Clinical Journal of the American Society of Nephrology | volume = 4 | issue = 11 | pages = 1878–1882 | year = 2009 | pmid = 19833911| pmc = | ref=harv}} <!-- {{sfn|McCarron|Geerling|Kazaks|Stern|2009}} -->
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* {{Cite techreport |title=Potassium- and sodium ferrocyanides |date=3 December 2001 |institution=European Commission: Scientific Committee on Animal Nutrition |url=http://ec.europa.eu/food/fs/sc/scan/out70_en.pdf |ref= {{harvid|European Commission|2001}} }} <!-- {{sfn|European Commission|2001}} -->
* {{Cite journal | last1 = Schmeda-Hirschmann | first1 = G. | title = Tree ash as an Ayoreo salt source in the Paraguayan Chaco | doi = 10.1007/BF02908207 | journal = Economic Botany | volume = 48 | issue = 2 | pages = 159–162 | year = 1994 | pmid = | pmc = | ref=harv}} <!-- {{sfn|Schmeda-Hirschmann|1994}} -->
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* {{Cite journal | last1 = Strazzullo | first1 = P. | last2 = d'Elia | first2 = L. | last3 = Kandala | first3 = N. -B. | last4 = Cappuccio | first4 = F. P. | title = Salt intake, stroke, and cardiovascular disease: Meta-analysis of prospective studies | doi = 10.1136/bmj.b4567 | journal = BMJ | volume = 339 | pages = b4567 | year = 2009 | pmid = 19934192| pmc =2782060 | ref=harv}} <!-- {{sfn|Strazzullo|d'Elia|Kandala|Cappuccio|2009}} -->
* {{Cite journal | last1 = Vaidya | first1 = B. | last2 = Chakera | last3 = Pearce | doi = 10.2147/DDDT.S12894 | title = Treatment for primary hypothyroidism: Current approaches and future possibilities | journal = Drug Design, Development and Therapy | pages = 1–11 | year = 2011 | pmid = 22291465| pmc = 3267517| ref = harv | volume=6}} <!-- {{sfn|Vaidya|Chakera|Pearce|2011}} -->
* {{Cite journal |last1=Weller |first1=Olivier |last2=Dumitroaia |first2=Gheorghe |url=http://antiquity.ac.uk/projgall/weller/ | title=The earliest salt production in the world: an early Neolithic exploitation in Poiana Slatinei-Lunca, Romania | journal=Antiquity | volume=79 | issue=306 |date=December 2005 |ref=harv}}
* {{Cite conference |last1=Weller |first1=Olivier |last2=Brigand |first2=Robin |last3=Nuninger |first3=Laure | title=Spatial Analysis of Salt Springs Exploration in Moldavian Pre-Carpatic Prehistory (Romania) |conference=Spatial dynamics of settlement and natural ressources: toward an integrated analysis over the long term from Prehistory to Middle Ages. University of Burgundy, Dijon, 23–25 June |publisher=ArchæDyn |year=2008 |url=http://hal.archives-ouvertes.fr/docs/00/41/60/26/PDF/archaedyn2008_weller_brigand_etal.pdf |ref=harv}}
* {{Cite book | last1 = Westphal | first1 = G. | last2 = Kristen | first2 = G. | last3 = Wegener | first3 = W. | last4 = Ambatiello | first4 = P. | last5 = Geyer | first5 = H. | last6 = Epron | first6 = B. | last7 = Bonal | first7 = C. | last8 = Steinhauser | first8 = G. | last9 = Götzfried | first9 = F. | doi = 10.1002/14356007.a24_317.pub4 | chapter = Sodium Chloride | title = Ullmann's Encyclopedia of Industrial Chemistry | year = 2010 | isbn = 3527306730 | pmid = | pmc = | ref=harv}} <!-- {{sfn|Westphal|Kristen|Wegener|Ambatiello|2010}} -->
{{Refend}}

==External links==
{{portal|Food}}
{{Sister project links|wikt=salt|commons=Salt|b=Cookbook:Salt|s=Littell's Living Age/Volume 4/Issue 34/Salt in Abyssinia|v=Extra info on food consumption#Salt/potassium intake|n=no|q=no}}
*[http://www.hagley.org/librarynews/introducing-carol-litchfield-collection-history-salt The Carol Litchfield Collection on the History of Salt], [[Hagley Museum and Library|Hagley Library]]

{{Salt topics}}
{{Means of Exchange}}
{{Herbs & spices}}
{{Consumer Food Safety}}
{{Use dmy dates|date=July 2014}}

{{Authority control}}

[[Category:Edible salt| ]]
[[Category:Food additives]]
[[Category:Sodium minerals]]

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  1. REDIRECT Sodium chloride
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