Salt, or sodium chloride, is necessary for the human body. It helps to control fluid balance and the functioning of the muscles and the nerves. The human body regulates how much salt it contains. If levels are too high, we get thirsty and drink, and this speeds up the elimination of salt through our kidneys.
Salt is sodium chloride, a combination of sodium plus chlorine. Forty percent of salt is sodium.
Most Americans consume too much salt and sodium, because their diet includes a lot of processed, restaurant, and convenience foods, and these can contain high amounts of salt and sodium.
Contents of this article:
What is salt used for?
Forty percent of salt is sodium.
The word salt comes from the Latin word "sal," meaning salt. It was once a valuable commodity, and it has been used as a currency for trading. The English word "salary" comes from the word salt.
Salt has long been used for flavoring and for preserving food. It has also been used in tanning, dyeing and bleaching, and the production of pottery, soap, and chlorine. Today, it is widely used in the chemical industry.
It commonly features at the table or in the kitchen as free-flowing table salt, rock salt, or kosher salt, and high levels of salt, or sodium, come hidden in everyday foods, from fast food to frozen chicken.
How does salt affect the body?
Salt is necessary for the human body. It regulates fluid levels, and it prevents low blood pressure. One study has found when rats were deprived of salt, they kept away from activities that they normally enjoyed. The researchers suggested, therefore, that salt could act as an antidepressant.
The Centers for Disease Control and Prevention (CDC) note that children consume nearly the amount of salt as adults, increasing the risk of childhood hypertension.
Too much salt has also been shown to overstimulate the immune system, leading to autoimmune diseases such as lupus, multiple sclerosis, allergies, and other conditions, according to research published in Nature.
Where do we find salt?
Salt occurs naturally in seawater and in solid rock.
Salt occurs naturally dissolved in seawater, or as a crystalline solid in rock salt.
The salt we eat today comes largely from the processed and convenience foods in our diet, but some natural and unprocessed foods also contain salt, or sodium.
It occurs naturally in meats, seafood, eggs, and dairy products.
One egg can contain up to 140 milligrams of sodium, 30 grams of milk contains around 180 milligrams, 200 grams of plain yogurt contains 40 milligrams, and 200 grams of natural, low-fat yogurt, 76 milligrams.
Some vegetables can be high in sodium. A 50-gram serving of raw celery can contain 140 milligrams of sodium, and a 60-gram serving of cooked spinach, around 120 milligrams. Other vegetables are low in salt, but canned vegetables have a far higher salt content.
Dietitians urge people not to add extra salt to their food, because enough is already added, if it is processed or packaged.
The American Heart Association (AHA) recommends limiting sodium consumption to 1.5 grams per day, equivalent to just over half a teaspoon of table salt. People with high blood pressure, diabetes or cardiovascular diseases should consume less. The average American currently eats more than 3.4 grams of salt every day.
Infants under 1 year should not be given salt because their kidneys are not matured.
Reading food labels
However, it is difficult to measure how much salt we are consuming, as it is hidden in many foods. More than 75 percent of salt eaten by Americans does not come from the salt shaker.
75% of salt eaten by Americans does not come from a slat shaker.
It is important to check the nutritional information on processed food to find out which ones are high and low in salt, or sodium, content, and what is the difference between salt and sodium.
Since salt is 40 percent sodium, if a label of nutritional information lists sodium instead of salt, it is necessary to multiply the amount by 2.5 to get the equivalent salt content.
If 100 grams of food contains 1g of sodium, the salt content of that food will be 2.5 g.
If a serving contains 1.4 g or less of sodium, the salt content is classed as low. A food with a high-sodium content is one that contains more than 20 percent of the recommended daily intake, or more than 480 mg per serving.
The U.S. Food and Drug Administration (FDA) recommend that people look carefully at low-salt claims on packaging. If a food is salt or sodium-free, for example, it can contain up to 5 grams of sodium per serving. Terms such as "light" or "reduced" sodium do not necessarily mean little salt, but that there is less salt than usual per serving.
Doctors recommend avoiding foods with a high salt content, and, if possible, selecting those with "no salt added."