1 00:00:00,280 --> 00:00:05,080 Speaker 1: This Day in History Class is a production of iHeartRadio. 2 00:00:08,680 --> 00:00:12,040 Speaker 1: Hello and welcome to This Day in History Class, a 3 00:00:12,160 --> 00:00:15,600 Speaker 1: show that believes every day tastes better with a pinch 4 00:00:15,640 --> 00:00:20,119 Speaker 1: of history. I'm Gay Bluesier, and today we're talking about 5 00:00:20,160 --> 00:00:23,960 Speaker 1: the time when a few sprinkles of salt became many Americans' 6 00:00:23,960 --> 00:00:37,040 Speaker 1: best bet for staving off a serious and unsightly illness. 7 00:00:38,920 --> 00:00:44,120 Speaker 1: The day was May one, nineteen twenty four. The first 8 00:00:44,320 --> 00:00:48,400 Speaker 1: iodized salt in the US went on sale at Michigan 9 00:00:48,440 --> 00:00:53,120 Speaker 1: grocery stores. It was exactly the same as regular table salt, 10 00:00:53,400 --> 00:00:56,760 Speaker 1: save for the addition of point zero one percent of 11 00:00:56,880 --> 00:01:02,000 Speaker 1: sodium iodide five. Michigan balt companies had added the compound 12 00:01:02,040 --> 00:01:04,840 Speaker 1: to their product at the urging of the Michigan State 13 00:01:05,000 --> 00:01:08,759 Speaker 1: Medical Society. Many in the Great Lakes region had long 14 00:01:08,840 --> 00:01:12,479 Speaker 1: suffered from iodine deficiency, and it was hoped that adding 15 00:01:12,480 --> 00:01:15,880 Speaker 1: a trace amount of the micronutrient to salt would correct 16 00:01:15,920 --> 00:01:20,520 Speaker 1: the problem. Larger companies, such as Morton Salt weren't convinced 17 00:01:20,520 --> 00:01:22,840 Speaker 1: that the benefits of the supplement would be worth the 18 00:01:22,920 --> 00:01:26,200 Speaker 1: trouble of having to explain its presence to customers, but 19 00:01:26,280 --> 00:01:28,840 Speaker 1: by the end of the year Morton had come around 20 00:01:29,120 --> 00:01:34,880 Speaker 1: and iodized salt became available nationwide. Adding iodine to salt 21 00:01:35,240 --> 00:01:38,080 Speaker 1: is similar to the practice of adding fluoride to water, 22 00:01:38,600 --> 00:01:41,800 Speaker 1: both their somewhat sneaky ways to make sure the public 23 00:01:41,840 --> 00:01:46,080 Speaker 1: gets an adequate amount of a helpful mineral. Unlike fluoride, however, 24 00:01:46,360 --> 00:01:50,880 Speaker 1: iodine is not naturally produced by the human body. Still 25 00:01:51,080 --> 00:01:54,080 Speaker 1: its essential in small quantities in order to keep the 26 00:01:54,080 --> 00:01:58,840 Speaker 1: thyroid gland functioning properly. Without it, the thyroid is unable 27 00:01:58,880 --> 00:02:03,000 Speaker 1: to produce thyroxide, a hormone that helps maintain crucial bodily 28 00:02:03,040 --> 00:02:07,000 Speaker 1: functions such as mental acuity. So if someone doesn't get 29 00:02:07,080 --> 00:02:10,359 Speaker 1: enough iodine in their diet, they may start to experience 30 00:02:10,440 --> 00:02:15,440 Speaker 1: mental impairment or even develop endemic goiter, a disease characterized 31 00:02:15,480 --> 00:02:19,200 Speaker 1: by a swelling of the thyroid gland, which usually presents 32 00:02:19,240 --> 00:02:21,800 Speaker 1: as a bulbous protrusion on the side of the neck, 33 00:02:22,080 --> 00:02:25,520 Speaker 1: called a goiter. The problem is iodine isn't all that 34 00:02:25,600 --> 00:02:28,400 Speaker 1: abundant in nature, though it can be found in trace 35 00:02:28,440 --> 00:02:32,600 Speaker 1: amounts just about everywhere by far, though it's most prevalent 36 00:02:32,760 --> 00:02:36,440 Speaker 1: in seawater, the world's supply of which holds roughly thirty 37 00:02:36,440 --> 00:02:40,280 Speaker 1: five million tons of iodine as a result, People who 38 00:02:40,360 --> 00:02:44,640 Speaker 1: live in coastal areas rarely develop iodine deficiency, as they 39 00:02:44,680 --> 00:02:47,240 Speaker 1: absorb plenty of it just through the water and air 40 00:02:47,440 --> 00:02:50,000 Speaker 1: around them. And of course, whether you live in a 41 00:02:50,040 --> 00:02:53,480 Speaker 1: coastal area or not, it's easy to work iodine into 42 00:02:53,480 --> 00:02:56,639 Speaker 1: your diet by consuming food from the ocean, such as 43 00:02:56,760 --> 00:03:00,440 Speaker 1: fish or seaweed. Of course, the flip side is that 44 00:03:00,480 --> 00:03:03,120 Speaker 1: if you don't live near the ocean and don't have 45 00:03:03,240 --> 00:03:06,240 Speaker 1: access to marine foods, you are unlikely to get the 46 00:03:06,280 --> 00:03:09,160 Speaker 1: iodine you need without going out of your way for it. 47 00:03:09,680 --> 00:03:12,680 Speaker 1: That was exactly the case for many Americans in the 48 00:03:12,680 --> 00:03:16,800 Speaker 1: early twentieth century. Communities that were far removed from the ocean, 49 00:03:17,000 --> 00:03:19,640 Speaker 1: such as those in the interior, Northwest and the Great 50 00:03:19,680 --> 00:03:23,520 Speaker 1: Lakes region, didn't have easy access to iodine rich foods, 51 00:03:23,800 --> 00:03:27,920 Speaker 1: and thousands of residents there developed thyroid problems as a result. 52 00:03:28,400 --> 00:03:31,880 Speaker 1: In fact, the condition was so common in those inland 53 00:03:31,960 --> 00:03:35,000 Speaker 1: areas that a whole stretch of land from the Rockies 54 00:03:35,200 --> 00:03:38,520 Speaker 1: to the Great Lakes to western New York became widely 55 00:03:38,560 --> 00:03:42,680 Speaker 1: known as the Goiter Belt. Medical professionals had begun to 56 00:03:42,760 --> 00:03:46,480 Speaker 1: raise the alarm about iodine deficiency during the draft for 57 00:03:46,600 --> 00:03:49,800 Speaker 1: World War One, when a shocking number of men had 58 00:03:49,800 --> 00:03:53,840 Speaker 1: to be disqualified from military service due to thyroid problems. 59 00:03:54,360 --> 00:03:58,360 Speaker 1: Around the same time, a physician named David Marine conducted 60 00:03:58,400 --> 00:04:01,840 Speaker 1: a series of studies on other iodine deficient school children 61 00:04:01,920 --> 00:04:05,680 Speaker 1: in Akron, Ohio. He and his colleagues found that adding 62 00:04:05,720 --> 00:04:08,680 Speaker 1: a small dose of iodine to the children's water each 63 00:04:08,800 --> 00:04:12,960 Speaker 1: day greatly reduced their chances of developing a goiter. By 64 00:04:13,000 --> 00:04:16,320 Speaker 1: the early nineteen twenties, then, the link between goiters and 65 00:04:16,400 --> 00:04:20,520 Speaker 1: iodine deficiencies had been clearly established, and so too had 66 00:04:20,560 --> 00:04:24,159 Speaker 1: a general solution to add trace amounts of iodine to 67 00:04:24,240 --> 00:04:27,880 Speaker 1: the diets of people in high risk regions. However, there 68 00:04:28,000 --> 00:04:30,800 Speaker 1: was still the question of how exactly to do that. 69 00:04:31,360 --> 00:04:33,760 Speaker 1: Most people wouldn't be willing to buy a jar of 70 00:04:33,839 --> 00:04:37,360 Speaker 1: iodine solution and mix it into their drinking water each day, 71 00:04:37,640 --> 00:04:41,400 Speaker 1: so a different distribution method would be needed. In nineteen 72 00:04:41,440 --> 00:04:46,159 Speaker 1: twenty two, doctor David Murray Cowie met that demand by 73 00:04:46,160 --> 00:04:50,400 Speaker 1: proposing that iodine in the crystalline form of sodium iodide 74 00:04:50,560 --> 00:04:53,760 Speaker 1: be added to the nation's salt supply. As a professor 75 00:04:53,800 --> 00:04:57,320 Speaker 1: of pediatrics at the University of Michigan. Cowie had been 76 00:04:57,360 --> 00:05:00,800 Speaker 1: deeply troubled by the prevalence of endemic goeidter in his state, 77 00:05:01,120 --> 00:05:05,120 Speaker 1: particularly among children. His search for a solution led him 78 00:05:05,120 --> 00:05:08,840 Speaker 1: to the process of salt iodization, which had already proven 79 00:05:08,839 --> 00:05:13,080 Speaker 1: effective at decreasing the incidents of goiter in Switzerland. Cowie 80 00:05:13,160 --> 00:05:16,440 Speaker 1: knew that adopting the Swiss method was the US's best 81 00:05:16,480 --> 00:05:19,680 Speaker 1: shot at combating one of the major public health problems 82 00:05:19,720 --> 00:05:23,279 Speaker 1: of the day. The tough part would be getting US officials, 83 00:05:23,560 --> 00:05:27,279 Speaker 1: salt producers, and the general public to agree with him. 84 00:05:27,520 --> 00:05:31,200 Speaker 1: It took several months of meetings with other physicians and educators, 85 00:05:31,400 --> 00:05:35,040 Speaker 1: but eventually Cowie got approval from the Michigan State Medical 86 00:05:35,120 --> 00:05:39,000 Speaker 1: Society to endorse and implement the production of iodized salt 87 00:05:39,320 --> 00:05:42,440 Speaker 1: for the good of public health. That backing made it 88 00:05:42,520 --> 00:05:45,640 Speaker 1: much easier to get the Michigan salt companies on board 89 00:05:45,720 --> 00:05:49,520 Speaker 1: with the idea. They agreed to start producing iodized table 90 00:05:49,560 --> 00:05:53,000 Speaker 1: salt and the same cylindrical containers as their old product, 91 00:05:53,279 --> 00:05:56,200 Speaker 1: except now with a label that called out the addition 92 00:05:56,320 --> 00:06:01,440 Speaker 1: of sodium iodide and its health benefits. Howie also approached 93 00:06:01,560 --> 00:06:06,240 Speaker 1: Morton Salt, the nation's leading brand, about incorporating sodium iodide 94 00:06:06,240 --> 00:06:10,600 Speaker 1: into their production process as well. However, the company declined, 95 00:06:10,800 --> 00:06:14,360 Speaker 1: believing that a formula change might hurt their sales. As 96 00:06:14,440 --> 00:06:17,520 Speaker 1: a result, Michigan grocery stores were the first in the 97 00:06:17,560 --> 00:06:21,880 Speaker 1: country to stock iodized salt. The locally sourced product first 98 00:06:21,880 --> 00:06:25,520 Speaker 1: appeared on shelves on May first, nineteen twenty four, and 99 00:06:25,640 --> 00:06:28,760 Speaker 1: sales were about as brisk as you'd expect in estates 100 00:06:28,880 --> 00:06:32,880 Speaker 1: so widely plagued by goiters. In the months that followed, 101 00:06:33,080 --> 00:06:37,640 Speaker 1: many Michigan residents reported positive effects from the new miracle salt. 102 00:06:38,080 --> 00:06:41,120 Speaker 1: The buzz was so good, in fact, that Morton quickly 103 00:06:41,160 --> 00:06:44,840 Speaker 1: reversed course and joined the cause. That fall, the company 104 00:06:44,920 --> 00:06:49,440 Speaker 1: became the first to distribute iodized salt nationwide, and within 105 00:06:49,480 --> 00:06:52,599 Speaker 1: a decade, the product accounted for more than ninety percent 106 00:06:52,800 --> 00:06:56,520 Speaker 1: of the US table salt market. During that same period, 107 00:06:56,720 --> 00:07:00,400 Speaker 1: the number of Michiganders afflicted with goiters find well, from 108 00:07:00,440 --> 00:07:04,560 Speaker 1: a staggering thirty percent of the population to just two percent. 109 00:07:05,200 --> 00:07:08,760 Speaker 1: Those results, and others like it, became a popular selling 110 00:07:08,800 --> 00:07:11,800 Speaker 1: point for table salt, with the presence of iodine being 111 00:07:11,880 --> 00:07:17,040 Speaker 1: proudly and prominently displayed on every company's label. Morton's Salt 112 00:07:17,120 --> 00:07:20,480 Speaker 1: didn't stop at goiter's though, but touted other various health 113 00:07:20,520 --> 00:07:24,360 Speaker 1: benefits as well. For example, a nineteen thirty four Morton 114 00:07:24,400 --> 00:07:30,280 Speaker 1: ad proclaimed quote, taller, heavier children protected against simple goiter 115 00:07:30,520 --> 00:07:34,800 Speaker 1: are found to be superior in development iodine. By protecting 116 00:07:34,880 --> 00:07:39,560 Speaker 1: children from simple goiter exerts a remarkable beneficial effect on growth. 117 00:07:40,000 --> 00:07:43,440 Speaker 1: If you want your children to escape being handicapped by 118 00:07:43,440 --> 00:07:47,920 Speaker 1: this disorder, begin to use Morton's iodized salt. At once, 119 00:07:48,720 --> 00:07:52,400 Speaker 1: most Americans took that advice, but over the years, the 120 00:07:52,440 --> 00:07:56,680 Speaker 1: iodine from salt became less and less necessary. That's because 121 00:07:56,760 --> 00:08:00,480 Speaker 1: food distribution has vastly improved in the last on hundred years, 122 00:08:00,800 --> 00:08:04,000 Speaker 1: resulting in a much more varied diet that generally provides 123 00:08:04,040 --> 00:08:08,920 Speaker 1: all the iodine a person needs. Nonetheless, the mineral continues 124 00:08:08,960 --> 00:08:11,600 Speaker 1: to be added to nearly seventy percent of the table 125 00:08:11,640 --> 00:08:15,600 Speaker 1: salt sold in the US. Today. Iodized salt may no 126 00:08:15,680 --> 00:08:18,520 Speaker 1: longer be the necessity it once was, but as a 127 00:08:18,560 --> 00:08:22,280 Speaker 1: low cost way to prevent another goiter epidemic, it's worth 128 00:08:22,360 --> 00:08:27,680 Speaker 1: keeping on hand just the same. I'm Gabe Lucier, and 129 00:08:27,800 --> 00:08:31,040 Speaker 1: hopefully you now know a little more about history today. 130 00:08:31,240 --> 00:08:34,480 Speaker 1: Than you did yesterday. You can learn even more about 131 00:08:34,520 --> 00:08:38,199 Speaker 1: history by following us on Twitter, Facebook, and Instagram at 132 00:08:38,240 --> 00:08:42,839 Speaker 1: TDI HC Show, and if you have any comments or suggestions, 133 00:08:42,960 --> 00:08:45,160 Speaker 1: feel free to send them my way by writing to 134 00:08:45,200 --> 00:08:49,560 Speaker 1: This Day at iHeartMedia dot com. Thanks to Chandler Mays 135 00:08:49,640 --> 00:08:52,120 Speaker 1: and Ben Hackett for producing the show, and thank you 136 00:08:52,160 --> 00:08:55,440 Speaker 1: for listening. I'll see you back here again tomorrow for 137 00:08:55,520 --> 00:09:02,400 Speaker 1: another Day in History class Pect the Future.