In 1811, Courtois noted a violet vapor arising from burning seaweed ash and Gay-Lussac subsequently identified the vapor as
iodine, a new
element. The Swiss physician Coindet, in 1813, hypothesized the traditional treatment of
goiter with seaweed was effective because of its
iodine content and successfully treated goitrous patients with
iodine. Two decades later, the French chemist Boussingault, working in the Andes Mountains, was the first to advocate prophylaxis with
iodine-rich
salt to prevent
goiter. The French chemist Chatin was the first to publish, in 1851, the hypothesis that
iodine deficiency was the cause of
goiter. In 1883, Semon suggested
myxedema was due to thyroid insufficiency and the link between
goiter,
myxedema, and
iodine was established when, in 1896, Baumann and Roos discovered
iodine in the thyroid. In the first 2 decades of the 20th century, pioneering studies by Swiss and American physicians demonstrated the efficacy of
iodine prophylaxis in the prevention of
goiter and
cretinism. Switzerland's
iodized salt program has been operating uninterrupted since 1922. Today, control of the
iodine deficiency disorders is an integral part of most national nutrition strategies.