“…The goitre centres of the USA are found throughout the whole length of the Appalachian range, in all states bordering on the Great Lakes, westward through North Dakota, and into the far western states of Montana, Idaho, Utah, Oregon and Washington where the incidence is particularly heavy. Except for isolated pockets of high incidence in Kansas-especially where it borders on Missouri-and in the New Orleans district of Louisiana, the great central plains are comparatively goitre-free, as also are the states on the Atlantic seaboard and the southern states of Mississippi, Alabama, Georgia and Florida.”
Reference: Kelly, F.C. and W.W. Snedden, “Prevalence and Geographical Distribution of Endemic Goitre,” in “Endemic Goitre” number 44. In ‘WHO Monograph Series.’, Geneva, Switzerland: World Health Organization, 1960, p. 27.