ARI SHAPIRO, HOST:
Nativity scenes are a Christmas tradition, of course, with baby Jesus surrounded by Mary, Joseph, the wise men and shepherds. Sometimes, if you look closely at the shepherds, you can see something unusual. NPR's Nell Greenfieldboyce explains why some of those unfortunate shepherds have large, misshapen throats.
NELL GREENFIELDBOYCE, BYLINE: These shepherds with swollen necks were painted, carved or sculpted hundreds of years ago in northern Italy. That's where Renzo Dionigi lives. He's with the University of Insubria in Varese. He's a retired surgeon with a passion for art.
RENZO DIONIGI: You know, when you retire, somebody just make crosswords, somebody watch TV. I like to study and go for museums.
GREENFIELDBOYCE: He says the mountains of northern Italy have soil and water that lack a vital nutrient, iodine. Without iodine, the thyroid gland in the neck can become abnormally large, creating a growth known as a goiter. This did not escape the attention of artists in the 16th and 17th centuries, who decorated the churches and chapels of the Sacri Monti, or sacred mountains.
DIONIGI: In all the Sacri Monti that I and my son visited, we have been able to observe representation of goiters very, very often.
GREENFIELDBOYCE: His son is also a surgeon. Together, they search art for diagnosable medical conditions. In a recent issue of the Journal of Endocrinological Investigation, they describe two carved wooden shepherds from the 16th century. They belonged to a Nativity scene. Both had huge growths on their necks. And Dionigi says they're not alone. There's a small church in Italy with a Nativity scene carved in 1694. It has a shepherd with a big goiter who's playing a horn.
DIONIGI: Then we found another person with goiter, but in a fresco, not in a sculpture. And that was a fresco in the lunette over the main door of the Aosta Cathedral.
GREENFIELDBOYCE: This was a shepherd playing a bagpipe in the Nativity. So why did artists inflict goiter on shepherds? Dionigi says one thing that contributes to iodine deficiency is a limited diet.
DIONIGI: That means that goiter is more often seen in poor people than in wealthy people, and that's why, probably, the poor shepherds are depicted with the goiters.
GREENFIELDBOYCE: He says sometimes artists put one on a tormentor or a persecutor to symbolize evil, but often, it just marks someone as humble and needy, like one sculpture of a man with a huge goiter kneeling in front of St. Francis.
DIONIGI: The size of that goiter in that sculpture is something like half a meter large. Can you believe it?
GREENFIELDBOYCE: I mean, would that happen clinically?
DIONIGI: Oh, yes. I saw some of them. I even operated some of them years ago.
GREENFIELDBOYCE: Iodine deficiency persists today. Angela Leung is an endocrinologist with UCLA and the VA Greater Los Angeles Healthcare System.
ANGELA LEUNG: Probably about a third of the world's population is iodine deficient.
GREENFIELDBOYCE: She says these deficiencies range from mild to moderate. Lack of iodine can make people feel tired, sluggish. And in pregnancy, it can stunt the fetus' developing brain.
LEUNG: One of the most popular measures to correct iodine deficiency is universal salt iodization.
GREENFIELDBOYCE: Iodide salt has been available in the U.S. since the 1920s. Before that, there was a so-called goiter belt around the Great Lakes and the northwest. Not all countries choose to iodide salt, and recent studies have found insufficient iodine intake in a number of countries, like Haiti, Russia, Iraq, Morocco and Italy.
Nell Greenfieldboyce, NPR News.
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