Page 41 - Summer2009

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will develop breast cancer during her lifetime. three times more likely to develop thyroid cancer than women with no
Thirty years ago, when iodine consumption such history, and there is a geographic correlation between the incidence
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one in twenty women developed breast cancer. of iodine is associated with a low incidence of breast cancer, and a low
Thirty years ago, consumption of iodized salt intake with a high incidence of breast cancer. 3
was higher than it is today; in addition a form Animal studies show that iodine prevents breast cancer, arguing for
of iodine was used as a dough conditioner in D FDXVDO DVVRFLDWLRQ LQ WKHVH HSLGHPLRORJLFDO ¿QGLQJV 7KH FDUFLQRJHQV
making bread, and each slice of bread con- nitrosomethylurea and DMBA cause breast cancer in more than 70 percent
WDLQHG PJ RI LRGLQH ,Q EUHDG PDNHUV of female rats. Those given iodine, especially in its molecular form as I ,
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started using bromide as a conditioner instead, KDYH D VWDWLVWLFDOO\ VLJQL¿FDQW GHFUHDVH LQ WKH LQFLGHQFH RI FDQFHU Other

which competes with iodine for absorption into evidence adding biologic plausibility to the hypothesis that iodine prevents
the thyroid gland and other tissues in the body. EUHDVW FDQFHU LQFOXGHV WKH ¿QGLQJ WKDW WKH GXFWDO FHOOV LQ WKH EUHDVW WKH
Iodine was also more widely used in the dairy ones most likely to become cancerous, are equipped with an iodine pump
industry as a teat cleaner thirty years ago than it (the sodium iodine symporter, the same one that the thyroid gland has) to
LV QRZ $FFRUGLQJ WR WKLV DUJXPHQW SHUFHQW soak up this element.

of the U.S. adult female population suffers from 6LPLODU ¿QGLQJV DSSO\ WR ¿EURF\VWLF GLVHDVH RI WKH EUHDVW ,Q DQLPDO
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7KH FRUUHODWLRQ RI LRGLQH GH¿FLHQF\ ZLWK their breasts, and iodine in its elemental form (I ) cures it.
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breast cancer is strengthened by reports in the As far back as 1966, Russian researchers showed that iodine effectively
MYSTERIES OF THE GOITER BELTS

The use of iodine supplementation in the goiter belts of the world—and these areas of endemic goiter and associated
problems exist in a great many countries—represents one of the first public health initiatives involving treatment of the
general population through the addition of a nutrient (in this case iodine) to water or food. “Mass prophylaxis” with iodine
was pioneered by two countries, the U.S. and Switzerland. The first controlled experiment took place in the early 1920s in
Akron, Ohio, where 5000 school girls took 0.2 g of sodium iodide daily in their drinking water for a period of ten days in
the spring and autumn while an equal number of controls drank untreated water. Of those taking the iodide who began the
experiment with a normal thyroid, none developed goiter, whereas 50 percent of the controls developed goiter. Following
this study, several cities in the Great Lakes region started to add iodide to central water supplies and iodized salt entered
the food supply. In Switzerland, many cantons introduced iodized salt, and those districts where it was used experienced
a decline almost to zero in the incidence of goiter (http://whqlibdoc.who.int/monograph/WHO_MONO_44_(p443).pdf).
In spite of these successes, mass iodine supplementation programs met with much resistance, especially as side effects
emerged. While the programs almost completely eliminated goiter, the prevalence of autoimmune thyroiditis increased in
areas with iodated water or in those using iodized salt. For example, a threefold increase in autoimmune thyroiditis was
noted once iodine deficiency was eliminated in an area of endemic goiter in northwestern Greece, an association confirmed
in clinical settings. In one study, dietary restriction of iodine reversed hypothyroidism in twelve of twenty-two patients;
seven of the patients with reversed hypothyroidism were re-fed iodine and became hypothyroid again (Anthony P Weet-
man, Autoimmune Diseases in Endocrinology, pp 50-51).
In addition, further epidemiological studies have cast doubt on the simple association of goiter with iodine deficiency.
Recently British researchers compared the distribution of endemic goiter in England and Wales with the distribution of
environmental iodine. Despite a very clear goiter belt through the west of England and Wales, they found no patterning in
the environmental iodine distribution and concluded that the presence of endemic goiter is no indicator of how iodine is
distributed in the environment or vice versa (Stewart AG and others. The Illusion of Environmental Iodine Deficiency. Envi-
ronmental Geochemistry and Health 25:165-170, 2003). Early observations of goiter belts in Switzerland recorded strange
distribution patterns, with villages completely free of goiter next to villages where goiter and cretinism affected many people,
and even the promoters of mass iodine supplementation have noted that iodine supplementation works best in conjunction
with an improvement of general nutrition.
Like all things in nature, the relationship of iodine status to thyroid health is resistant to simplified explanations. Many
other nutrients contribute to thyroid health besides iodine, and numerous environmental and industrial toxins can depress
thyroid function. And the body’s ability to use iodine almost certainly has a genetic component. The moral: be wary of
one-size-fits-all solutions and if you choose to supplement with iodine, be carefully observant of any side effects.

SUMMER 2009 Wise Traditions 39