The Truth Behind Tasmanian’s Having Two Heads
It’s a school yard joke “Oh you’re from Tasmania? Where’s the scar from your second head?”
The joke has been around for so long that we’ve forgotten where it originated. But nuclear medicine professor Paul Ac Richards might have a plausible explanation.
“Tasmania is mildly iodine deficient, and during the 19th and 20th centuries in particular, there was a tremendous amount of goitre in Tasmania.”
Professor Richards said. “It was just taken for granted that you had a goitre.”
Goitre is the swelling of the neck due to the enlargement of the thyroid gland. Worldwide 90% of goitre is caused by an iodine deficiency. Tasmania became iodine deficient due to an ice age leaching the iodine from the top soil.
These goitres would grow as large as footballs – easily sizable enough to be thought of as a second head like growth.
And when these goitres were removed they would inevitably lead to a scar on the neck, fuelling two head jokes.
The most famous victim of goitre was the first woman to be elected to the Australian House of Representatives; Dame Enid Lyons. Before the 1949 federal election she had had goitre removal surgery.
“That’s why she wore scarves and necklaces in all her photos after that.” Professor Richards said.
Nowadays thyroid conditions are low in Tasmania but that did come through trial and error.
In 1949 the State Government provided daily potassium iodine tablets to schoolchildren, but the program was eventually dropped as it failed during the school holidays.
The 1960’s again saw widespread supplementation of iodine but it was too effective and caused a boom of thyrotoxicosis; that is hyperthyroidism caused by excessive hormone production.
Professor Richards notes that today Tasmania has a tenuous balance with iodine. “Iodised salt in bread is now mandatory, and iodine is a key ingredient in the products used to clean milk vats and cows’ teats before milking. But all the dairy companies have to do is switch to a chlorine-based cleaning product and we’ve got the same problem all over again.”
So that’s the word Tassies! Eat your bread, and drink your milk and you’ll avoid growing a second head.