Salt Sea or Iodized Table Salt: Why should we use iodized salt?

I've read many articles recently extolling the virtues of Sea Salt, and claiming for a variety of reasons, that Sea Salt is a healthier choice then plain old iodized salt. Sea salt does have a larger crystal, and sits on the surface of the food This can make your food seem saltier at first, because you taste the salt sooner, and may, in fact, encourage you to eat less salt.

This theory only applies to salt added after cooking, though. A teaspoon of salt is still a teaspoon of salt, regardless of it's origins, and whether it has been iodized or is natural or flavored sea salt. I agree wholeheartedly that cutting down our salt intake is a healthy choice, but claiming that one salt is healthier than another requires some research.

Iodine is an element in family of chemicals called halogens, which readily combine with other elements to form salts.

At room temperature, iodine is a shiny, black, nonmetallic crystal. When heated, Iodine becomes a violet-colored mist with an odor similar to chlorine. Pure Iodine is toxic, but dissolved in alcohol (tincture of iodine), it is commonly used as an antiseptic.

Iodine occurs in a compound form, most commonly potassium iodide, and is found in seawater, soil, and rocks. In Chile, the world's largest producer of commercial iodine, it is found as sodium iodate, a naturally-occurring impurity in sodium nitrate deposits.

Iodine also occurs naturally in some foods - kelp, and salt-water fish and shellfish. Milk, egg yolks, watercress, and some fruits also contain small amounts of iodine.

The short answer, is that iodine prevents goiter - an unsightly and painful swelling of the throat and neck caused by nodules in the thyroid gland - but how did iodine come to be added to table salt?

What causes Goiter?

Goiter can be caused by over-production of thyroid hormone, as in Grave's disease. Hashimoto's disease, which causes the thyroid gland to produce too little hormone, also causes goiter. Goiter is most commonly caused, though, by a lack of iodine in the diet.

Most plants and animals require a small amount of iodine for normal growth. Man and other mammals concentrate iodine in the thyroid gland, where it helps regulate the metabolism. Without enough iodine, a person's growth may be stunted, and they are at risk of developing goiters.

Treatment of Goiter

Goiter has been with us for as long as diseases have been recorded in history. The ancient Chinese were the first to find an effective treatment, using kelp (seaweed) and burnt sea-sponge. Though no-one understood how kelp and sea sponges cured these swellings, the practice was well established by the Middle Ages.

This treatment was so effective, it gradually made its way to every country where people were affected by goiter.

In the 1800s, goiter was a common ailment, sometimes referred to as a "poor man's disease," as it occurred frequently in poorer areas, and was thought to be linked to poor diet or bad water. Goiter was most common in women and children, especially pregnant women. In extreme cases, very large swellings could make swallowing and even breathing very difficult for the sufferer.

The development of better antiseptics and anesthetics in the 1800s led to surgical treatment of goiter. At first, surgeons removed the whole thyroid gland with, as they soon discovered, disastrous results. The patients survived, but removing the whole gland led to extreme drying of the skin, hair loss, premature aging, depression, and rapid weight gain.

These side effects led surgeons to attempt removing only the nodules that invaded the thyroid gland. They were sometimes unable to save the whole gland, but even a partial gland enabled the patient to make a full recovery.

• In 1814 J. J. Colin discovered that iodine reacts with starch, producing a brilliant blue color, allowing iodine to be detected in minute quantities.
• In 1819, Jean-Baptiste Dumas proved that the sea-sponges used to treat goiter contained iodine.
• By 1820, iodine had been discovered in kelp.
• In the mid-1800s, French chemist, Jean Boussingault, suggested that iodine compounds might be used to cure goiter after a young doctor asked him to analyze samples of salts used by South American Indians to treat goiter, and Boussingault found iodine in the salts.
• Despite these advances, goiters were still epidemic in areas where the soil was lacking in key minerals. Without iodine in the soil, it never enters the food chain and therefore never enters the human body.
• Though the search for a cure continued, researchers and doctors began to look for cost-effective ways to prevent goiter. The solution seems obvious now - to prevent goiter, a way needed to be found to introduce iodine into everyone's diet. The mechanism for delivery took a while longer to be discovered, though.
• David Marine, a pathologist from Johns Hopkins who was interested in goiters, revived French chemist Jean Baptiste Boussingault's ideas. Boussingault had noticed in the 1830s that goiters simply did not occur in areas where people used crude sea salt that was naturally rich in iodine.
• As almost everyone had at least a modicum of table salt in their diets. Since the amount of iodine needed to prevent goiters was so tiny, Marine reasoned that adding iodine to table salt would be a perfect solution - cost effective and efficient.
• In 1924, Dr. David Cowie, Professor of Pediatrics at the University of Michigan, enlisted the American salt manufacturers to introduce iodized salt, effectively eliminating goiter in North America, and preventing all other symptoms of iodine deficiency.

Today, the conditions that cause goiter - the lack of iodine in the soil, or lack of access to a marine-based iodine-rich diet - have been negated by the simple introduction of iodized table salt.

We still need to avoid processed foods. They are high in sodium to which, interestingly, no iodine has been added. Iodine is only required to be added to table salt.

Any virtue Sea Salt may have, beyond its obvious cachet as a "natural" product, hinges on its iodine content. Some forms of raw sea salt are iodine rich, and these should be chosen above all others. Fancy, flavored salts and exotic "designer" salts may add piquancy to our food, but unless they add necessary iodine to our diets, they are a far less health-conscious choice than plain table salt, regardless of how much they cost, or how much or little we use.

© 2011 Elle Fredine, All rights reserved