Researchers say people are getting less iodine due to changes in diet and food manufacturing
Iodine deficiency affected children in large swaths of the United States a century ago and the problem, which had disappeared through the food industry, is returning with changes in diet and food manufacturing.
The problem appeared to be overcome after some food manufacturers began adding it to table salt, bread and some other foods, in one of the great public health success stories of the 20th century, the Associated Press reported Monday ( AP).
But currently, people are getting less iodine due to changes in diet and food manufacturing.
Although most people are still getting enough, researchers have increasingly reported low iodine levels in pregnant women and others, raising concerns about the impact on their newborns.
And there are also a very small but growing number of reports of iodine deficiency in children.
“This needs to be on people’s radar,” warned Monica Serrano-Gonzalez, a doctor at Brown University in Providence, Rhode Island.
Iodine is a trace element found in seawater and some soils – particularly in coastal areas. A French chemist discovered this accidentally in 1811, when an experiment with seaweed ash created a purple cloud of vapor.
The name iodine comes from a Greek word meaning violet color.
Later in the century, scientists began to understand that people need certain amounts of iodine to regulate their metabolism and stay healthy, and that it is crucial for developing brain function in children.
One sign of iodine insufficiency is swelling of the neck, known as a goiter. The thyroid gland in the neck uses iodine to produce hormones that regulate heart rate and other body functions. When there is not enough iodine, the thyroid gland increases in size as it speeds up to compensate for the lack of iodine.
Public health experts realized they couldn’t solve the problem by feeding everyone seaweed and seafood, but they learned that iodine can essentially be sprinkled on table salt.
Iodized salt was first available in 1924. By the 1950s, more than 70% of U.S. households used iodized table salt. Bread and some other foods were also fortified with iodine, and iodine deficiency became rare.
But diets have changed. Processed foods now make up a large part of the American diet, and although they contain a lot of salt, they are not iodized. The main bread brands no longer add iodine. For people who salt their food, it is now customary to use kosher salt, Himalayan rock salt, or other non-iodized products.
“People have forgotten why there is iodine in salt,” said Elizabeth Pearce of Boston Medical Center, who leads the Iodine Global Network, a nongovernmental agency working to eliminate iodine deficiency disorders.
Pearce noted a reported 50% drop in U.S. iodine levels among Americans surveyed between the 1970s and 1990s.
