Salted_ A Manifesto on the World's Most Essential Mineral, With Recipes - Mark Bitterman [19]
Chlorine reacts with water, yielding hydrochloric acid, which burns the skin and mucus membranes. You can smell chlorine in very minute quantities of just 3.5 parts per million (ppm). It causes throat irritation at 15 ppm, coughing at 30 ppm, and will kill you in a few deep breaths at 1,000 ppm. The German military used chlorine gas as a chemical weapon early in World War I; hence, it has the inglorious distinction of being among the first fatal chemical gases used in modern warfare.
Chlorine and sodium are both so reactive that they’re never found in their elemental form in nature. Instead, most sodium and chlorine exist as sodium chloride, in crystalline form in salts and in ionic form in brines. Brine is a major feedstock for the chemical industry, which uses the chloralkali process of passing electricity through a brine to produce chlorine and sodium hydroxide, the two agents at the heart of the modern chemical industry. The chloralkali process accounts for about half of the salt consumption worldwide, supplying chemicals used in making everything from paper to medicine.
SALT IN FOOD
Thou hadst better eat salt with the Philosophers of Greece, than sugar with the Courtiers of Italy —Benjamin Franklin
Ideally, we would get all the salt we need from natural, whole foods. However, all animals, humans included, have always had to compete for food. Since animals first left the sea (where the balance in the ancient salt water they swam in was almost identical to the saltiness of their bodies) to walk the earth, they have had to seek outside sources for salt as a supplement.
There are just two ways to get enough salt in your diet to survive: eat animal flesh or eat some salt. A 120-gram serving of stewed rabbit contains about 20 milligrams of sodium, the equivalent of 50 milligrams of salt. The same size portion of beef sirloin contains 55 milligrams. There is barely any salt at all in plants. Edible forms of both meat and salt take considerable effort to procure. Perhaps, because the availability of salt in nature is so sporadic, and its importance to our survival is so constant and absolute, we have developed these intense physiological salt cravings and such sophisticated taste receptors for recognizing salt.
For these same reasons, our bodies are very good at regulating sodium levels. In fact, the systems regulating water and sodium levels in our bodies are perhaps biology’s most well-developed and effective systems. With a compromised immune system, we may get sick. With a compromised endocrine system, our body fails to manage metabolism and tissue function. With a compromised sodium/water regulatory system, all the functions of our body—including immune, endocrine, nervous, and digestive systems—simply stop working.
Physiologically speaking, too much salt is not as severe a problem as too little, and it’s highly unlikely to occur on a diet of unprocessed foods. Our bodies have several mechanisms to deal with a spike in salinity. One way is to increase water intake to dilute the level of sodium in our bodily fluids. (Conversely, decreasing the amount of water in our bodies raises sodium levels and triggers a sense of thirst, prompting us to take in water to bring our sodium levels back in balance.) Our kidneys are also incredibly efficient at eliminating sodium; some research has suggested that healthy kidneys supported with enough water can eliminate as much as three pounds of salt in a day. If your body has too much sodium, it will do a very good job of bringing things back into balance quickly.
SIFTING SALT FROM THE SEA
Mankind can live without gold … but not without salt —Cassiodorus
All salt originates in the sea, where it swirls around in a solution of many dozens of ionized minerals and compounds. Chloride and sodium are the major ions giving the sea its salinity, which is the generic term for the concentration of dissolved salts in seawater.