NEW YORK — A 13-year-old boy presented to a medical clinic with a rapidly swollen neck, leaving doctors baffled. Initial tests ruled out their preliminary concerns, but further investigations uncovered the overlooked issue: iodine deficiency.
A century ago, iodine deficiency was a widespread problem, particularly affecting children in various regions of the United States. This issue was largely mitigated after food manufacturers began fortifying table salt, bread, and other products with iodine, marking a significant achievement in public health during the 20th century. However, contemporary dietary changes and food production methods have led to a lower iodine intake among segments of the population.
While the general population continues to receive adequate iodine levels, researchers have noted a troubling trend of diminishing iodine in pregnant women and certain individuals, raising alarms about potential effects on newborns. There has also been a slight but concerning increase in reported iodine deficiency among children, highlighting a need for awareness. “This issue should be on people’s radar,” stated Dr. Monica Serrano-Gonzalez, a physician from Brown University who treated the boy in question in 2021 in Providence, Rhode Island.
Iodine is a trace element naturally found in seawater and specific soil types, predominantly in coastal regions. It was inadvertently discovered by a French chemist in 1811 during an experiment with seaweed ash, producing a violet vapor from which the term “iodine” derives. Over time, scientists recognized the essential role iodine plays in regulating metabolism and its vital importance in cognitive development for children.
One of the indicators of iodine deficiency is the development of a goiter, which is a swelling of the neck caused by the thyroid gland’s enlargement. The thyroid requires iodine to produce hormones that influence heart rate and a host of other bodily functions. In the absence of sufficient iodine, the thyroid compensates by enlarging itself, leading to this visible swelling.
During the early 20th century, goiters were relatively common among children in certain regions of the U.S., particularly within a “goiter belt” that extended from the Appalachians to the Great Lakes and into the Northwest. Some affected children exhibited symptoms associated with a syndrome previously termed “cretinism,” which included stunted growth, deafness, and cognitive impairments.
Realizing that simply increasing the consumption of seafood and seaweed wouldn’t solve the deficiency problem, public health officials devised a solution: fortifying table salt with iodine. Iodized salt made its debut in 1924, leading to significant adoption—by the 1950s, more than 70% of American households used iodized salt. Bread and other foods also began to be fortified, drastically reducing the prevalence of iodine deficiency.
However, as diets evolved, a significant portion of the modern American diet now comprises processed foods, which often contain non-iodized salt. Major bread brands have stopped adding iodine, and the boy’s case highlighted these dietary shifts, as he was diagnosed with mild autism and had a selective diet that consisted largely of specific bread brands and peanut butter.
Furthermore, many consumers today prefer using alternative salts such as kosher salt or Himalayan salt, which are typically non-iodized. “People seem to have forgotten the reason iodine is present in salt,” remarked Dr. Elizabeth Pearce from Boston Medical Center, who is involved with the Iodine Global Network, an organization dedicated to addressing iodine deficiency disorders. She pointed out a significant drop—by about 50%—in iodine levels among Americans from the 1970s to the 1990s.
Although overall iodine intake appears to be declining, experts indicate that most Americans are still consuming adequate amounts of it. However, they express particular concern for women and children, who are at heightened risk for iodine deficiency. The American Academy of Pediatrics recommends that pregnant and breastfeeding women consume 150 micrograms of iodine daily, which can be achieved with only a half to three-quarters of a teaspoon of iodized salt.
Recent studies in the past 15 years have revealed rising instances of mild iodine deficiency among pregnant women. A study conducted at Michigan State University involving approximately 460 pregnant women in Lansing found that around 25% of them were not meeting their iodine needs. Many prenatal vitamins lack iodine, leading researchers like Jean Kerver, the study leader, to advise that pregnant and breastfeeding women verify that their multivitamins include this essential nutrient.
Moreover, even mild iodine deficiency has been linked to lower IQs and language delays in children, although there is ongoing debate about the thresholds at which these issues arise. Experts maintain that further research is warranted to evaluate the implications of iodine deficiency on recent U.S. populations.
Dr. Serrano-Gonzalez noted that her team has encountered four additional cases of iodine deficiency among children in their clinic in Providence. “We are worried that this might be on the rise, particularly in patients who have limited diets,” she stated.
