A National Evil

As​ far as the archivist knew, the 48 box files locked in an attic above the Institute for the History of Medicine at the University of Bern had never been opened. They contained a mass of handwritten letters, glass-plate negatives, annotated offprints, minutes of meetings, and piles of press clippings almost too fragile to touch. Gothic newsprint hailed victory over a ‘national evil’. ‘It sounds like a fairy tale,’ the front page of a 1922 copy of Tages-Anzeiger said.

At the turn of the 20th century, the Swiss were plagued by strange, interlinked medical conditions, which existed elsewhere to a degree, but in Switzerland were endemic in more than 80 per cent of the country. It was a curse that had a mark: the goitre, a bulge of flesh protruding from the front of the neck, sometimes so large that it weighed on the windpipe, giving bearers a characteristic wheeze. It was often disguised by collars and high necklines, but its true extent is laid bare by conscription data. In 1921, nearly 30 per cent of 19-year-old Swiss conscripts had a goitre. In the cantons of Luzern and Obwalden, one in four men were exempt from military service as a result of goitres so large they struggled to breathe. For every man with a goitre, three women suffered from the condition. Children were the most vulnerable of all: in 1921, in the city of Bern, 94 per cent of schoolchildren had some swelling of the neck and almost 70 per cent had a goitre.

In some parts of the country, one in ten babies was born with what was then known as cretinism. The afflicted grew little more than a metre tall, and had compressed features, thick skin, thin hair and distended bellies. Those with the disease were unable to hear or speak and were profoundly brain-damaged. In 1922, there were at least five thousand people with the condition in Switzerland. Across the country, one person in six hundred was born deaf – a rate five times the international norm. In Zurich and Bern, the most affected cantons, the rate was one in two hundred. Another malaise also affected the Swiss: brain fog – a sense of exhaustion, of hopelessness, of always being cold.

The burden of these illnesses is hard to overstate. At a time when even young children were expected to help support the family, the birth of a cretin could be a catastrophe. Through it all, there was the fear of what a birth might bring; the fear that it was their fault. This was an ancient evil, noted by Vitruvius and Pliny the Elder. For tourists in the 19th century, the afflicted were one of the sights. ‘On comprend les crétins dont [pullule] la Suisse,’ Victor Hugo wrote from Bern in 1839. ‘Les Alpes font beaucoup d’idiots.’ Mark Twain, in 1880, reported the words of an English traveller: ‘I have seen the principal features of Swiss scenery – Mount Blanc and the goitre – now for home.’

Cretinism and goitre were among the great medical mysteries of 19th-century Europe. The overlap of the conditions was a source of fascination, as was their geographical specificity. Scientists, medics and armchair experts flocked to the Alps, seeming to discount nothing in their investigations: landscape, elevation, atmospheric electricity, snow melt, sunlight (too much and too little), ‘miasma’, bad beer, stagnant air, incest and ‘moral failure’. They collected information on the minutiae of life in affected areas, then cross-referenced their reports, following the contemporary medical wisdom which held that all diseases had multiple causes. Did groundwater interact with sunlight to produce goitre? Might a certain combination of air pressure and elevation create a cretin? In 1876, a list of the most promising theories was published; it featured forty different hypotheses.

In 1883, the scale of the problem became evident when Dr Heinrich Bircher, a lecturer in surgery at the University of Bern, published a survey of goitre in every town and village in Switzerland. Numbers were low in the Jura mountains and in the southern canton of Ticino, but spectacularly high almost everywhere else. In Deisswill, a suburb of the capital, Bern, 94 per cent of young men had large goitres. Villages in the cantons of Zurich and Fribourg reported that one third of inhabitants were deaf. In Kaiseraugst, a short distance up the Rhine from Basel, one person in three was a cretin. Yet the clarity of the data seemed to deepen the mystery: the village of Kaisten was severely affected by the plague, but Effingen, just ten kilometres away, was not.

As the new science of microbiology began to explain one disease after another, researchers competed to discover a micro-organism for goitre. There were two main theories: a water-borne pathogen and a contagious organism in or around the goitre itself. Meanwhile, theories of ‘racial hygiene’ were gaining ground, with their simple but brutal prescriptions. In Cretinous Degeneracy (1923), the Swiss doctor Ernst Finkbeiner asserted a genetic origin for the disease and offered his solution: ‘To exclude from reproduction anyone even touched by the endemic.’ Parents, siblings, distant cousins.

From Rudolf Virchow to Alexander von Humboldt, Europe’s greatest scientists had tried to solve the goitre problem. Yet the solution, when it came, did not emerge from a university or research institution, or even a hospital, but from a young doctor called Heinrich Hunziker, a GP in Adliswil, a small town on the western edge of the Zurichsee. Hunziker was also a poet, who wrote short, formally precise verses of yearning and revelation that he published in slim volumes. He was 34 when, in May 1914, he stood up to speak at the Zurichsee Doctors’ Society. Everyone was looking in the wrong place, he said. The cause of the conditions was not a germ or genetic defect, but something missing. Not an agent, but an absence.

Touch​ your neck, just above the base. Beneath the skin, too thin to be felt, is your thyroid, a gland shaped like a butterfly, with wings spread either side of your throat. It produces two hormones that act on almost every cell in your body, influencing nearly all physiological processes: from metabolism to brain function, body temperature to growth. These hormones contain the element iodine. Your body cannot create iodine, so to produce the hormones, you must draw iodine from the world around you: mainly from food, but also from drink and the air you breathe. You only need a tiny amount – an adult requires 150 micrograms a day (fifteen hundredths of a milligram) – but without it, the consequences are dramatic. Your thyroid, desperate for iodine, begins to expand, to filter iodine more effectively from your blood. Over time, this growth becomes a goitre, but even this adaptation may not be enough. Deprived of thyroid hormones, your heart rate slows. You begin to feel cold and exhausted. Your muscles ache and become weak. Soon, your joints begin to swell, your skin dries out, your hair thins. Your voice becomes a rasp. You gain weight, and an all-consuming brain fog settles over you, making it hard to think, to remember things, to feel joy. When children are deprived of these hormones, their growth is damaged. In utero, the effects can be catastrophic. A foetus draws on its mother’s thyroid hormones to grow, and without them, its development is distorted, leading to miscarriage and birth defects, including deafness. In the first trimester of pregnancy, severe iodine deficiency in the mother will cause an embryo to miss crucial stages of development: the child will be born a cretin.

Iodine can be found almost everywhere in the world. It is abundant in ocean water, and when prehistoric seas receded, the element remained on the land, where it is drawn up by plants, consumed by animals and returned to the soil. This inheritance is kept stable by an ‘iodine cycle’: what is washed out by the rain is replaced by iodine vapour blown far inland. But not in Switzerland. In the last ice age, a permanent ice sheet formed over the Alps. Up to one kilometre thick, its tremendous weight ground against the terrain. It thawed and refroze in stages, and with every thaw, meltwater washed out the rubble. Over the course of 100,000 years, this ice sheet tore the top 250 metres of rock and soil from the surface of the Swiss Central Plateau. At its peak, about 24,000 years ago, it extended across all the northern cantons. It did not reach the Jura or Ticino. In 1964, Dr Franz Merke, a Basel surgeon, showed that the extent of the ice sheet ‘corresponded precisely’ with the prevalence of goitre: Switzerland had been stripped of its iodine. This was a decade after it had finally been proved that iodine deficiency caused the linked medical conditions in the region. Forty years earlier still, in 1914, hormones had only just been defined (in 1905, by Ernest Starling at UCL), nutritional science had barely begun (with Casimir Funk’s 1912 hypothesis on vitamins), and the chemical composition of Swiss soil was unknown. Despite this, almost everything Hunziker argued turned out to be true.

Iodine was discovered in 1811, and by the time Hunziker gave his speech to the Zurichsee Doctors’ Society, it was used in a bewildering variety of treatments, from cough medicines to skin creams and aphrodisiacs. ‘There was hardly any disease for which it was not recommended,’ Merke wrote in his 1971 book, History and Iconography of Endemic Goitre and Cretinism (first published in English in 1984). But in the 19th century and beyond the element had a grim reputation: it was notorious for inducing the Jod-Basedow effect, a frightening, sometimes fatal condition characterised by bulging eyes, rapid heartbeat, tremor and agitation. Iodine was both famed as a medicine and feared as a poison.

Hunziker, by contrast, talked about it as a food, an essential part of everyday diet. This was a bewildering leap, and his claims about the amount required were no less startling. Treatments in Swiss pharmacies might contain a daily dose of one gram of iodine, but Hunziker argued that a ten-thousandth of this was all that was required, and that the Jod-Basedow effect (now known as iodine-induced hyperthyroidism, or IIH) was a sign of overdose. Indeed, he claimed to have tested tiny doses for years, with no ill effects: during treatment, goitre shrank; when treatment ceased, it returned. Goitre was not an alien growth or an infection, merely an enlarged thyroid. Hunziker addressed cretinism (now known as congenital iodine deficiency syndrome) with logic: in the rare instances when babies are born without a thyroid, they suffer only after birth, meaning that in utero they must use their mother’s thyroid hormones. Goitre-related birth defects – from deafness to cretinism – must therefore be due to the mother’s lack of iodine, probably in the first trimester. To end the ancestral curse, all the Swiss people needed was a tiny, daily dose of iodine delivered in an everyday commodity: table salt.

Sodium chloride is the perfect vehicle for iodine. We need a small amount of sodium every day in order to function, and, like iodine, we cannot create it in our bodies. Unlike iodine, sodium is something we crave. Yet our appetite is swiftly sated: people struggle to take the correct dose of pills or tonics, but they consume a remarkably consistent amount of salt. Just as important, iodine in such minute quantities does not change salt’s taste. (Whatever chefs might claim, this fact is well established: in 1995, Unicef, concerned about the sensitivity of children to odd flavours, commissioned a study in which rice was prepared with salt iodised at ten times the maximum recommended concentration. In double-blind taste tests, the iodine was undetectable.)

In 1915, Hunziker’s speech was published as a 24-page booklet. It was brief and beguilingly simple, but in Switzerland criticism was fierce. Shortly after its publication, a leading doctor at the University of Zurich, Adolf Oswald, wrote a scathing rebuttal in the country’s most authoritative medical journal demanding that the proposal ‘must be vigorously opposed’. To his detractors, Hunziker was historically illiterate and his theory a recipe for mass poisoning. That iodine had some effect on goitre was well known, but it had been thoroughly discredited as cure or prophylaxis – not just once, but numerous times. Similar ideas to Hunziker’s had been in circulation for a century. In 1820, an attempt to treat goitre with iodine by the Geneva doctor Jean-François Coindet left the physician hiding from his furious, overdosed patients. In the 1860s and 1870s, iodised salt experiments conducted in three French départements ended in disaster, with mass outbreaks of Jod-Basedow.

In 1851, a remarkably similar iodine deficiency theory had been rejected by the French Académie des Sciences. Adolphe Chatin, the young director of the Paris School of Pharmacy presented exhaustive measurements of iodine concentrations in water, soil and vegetables to support his claim that the absence of minute quantities of the element gave rise to goitre. Yet his theory was dismissed: such tiny quantities of a single substance could not, he was told, have such a dramatic impact. The use of iodine as a goitre prophylaxis was proposed again in 1898, 1909 and 1912. In 1911, the US researcher David Marine announced that he had used iodine to prevent goitre in freshwater trout, though he stopped short of endorsing an iodine deficiency theory. He thought the element probably counteracted another, goitre-creating agent, much as quinine acts on the symptoms of malaria. In key respects, notably the quantities of iodine required, Hunziker’s theory really was new, but these subtleties did little to stem the opprobrium.

High​ in the Alps, Otto Bayard – another country doctor, two years younger than Hunziker – was following the debate. He had studied in Dublin, been to China and Indonesia as a ship’s doctor, and after a Red Cross mission to the Balkans was now, in 1918, back in his native Valais, in a Zermatt emptied of its prewar crowds of tourists, living at the end of a railway line whose two daily steam trains only ran in the summer months. For half the year, it was all but cut off from the world, and visiting a patient could mean a twenty-hour trip on the back of a mule.

Bayard was sceptical about Hunziker’s theory, but he wanted to know what worked, and knew that, for all the talk, tiny daily doses of iodine had never been put to the test. So he began to devise a new kind of experiment: in an early version of a dose-response trial, he prepared table salt iodised at five different concentrations to give to five families in a goitre area for five months. He worked alone, mixing close to 100 kg of salt with his snow shovel, turning it over until he was sure the potassium iodide was evenly spread. Then, loading up his mule, he set out for Grächen, a remote village even by the standards of upper Valais. It had no train station and no road, and sat on a thin shelf of land, one and half hours by mule from the bottom of the valley. It was badly affected by goitre; 75 per cent of the village schoolchildren had enlarged thyroid glands. Bayard took measurements and photographs, and gave the families iodised salt. He left salt for the cows, to iodise their milk, and for the bakery, so that it would be in the bread. The experiment ran through the winter, the half of the year when children went to school. When Bayard returned in spring, not only had the five families not been poisoned, they all had slimmer necks. He had given the lowest dose – just 4 milligrams of potassium iodide per kilogram of salt – to the family of Theophil Brigger, a farmer who was raising seven children, aged six to fifteen, alone. His children were transformed.

Bayard broke the news of his solo endeavour just as word reached Switzerland of a successful experiment by David Marine in Akron, Ohio, in which iodine tablets were dispensed to schoolgirls (Marine’s results were published in 1917 in the US, but communication to Europe was disrupted by the war). Bayard set to work on another winter project to prove that the salt would work at scale; not for five families, but for two villages. He chose Grächen again and a village of the same size on the other side of the valley called Törbel. With funding from the Swiss Health Authority, he formalised his operation, preparing highly concentrated batches of iodised salt to be given to one trusted person from each community, along with a small set of scales and precise instructions. At their village salt depots, these representatives painstakingly portioned out three tonnes of salt, a kilogram at a time, and when Bayard returned six months later, the goitres had gone. He continued his experiments in Grächen, adjusting the dose, until, at the end of 1921, he received an invitation to present his results at the new Swiss Goitre Commission in Bern.

There were​ sixteen men at the first commission meeting on 21 January 1922, almost all of them senior figures in Switzerland’s top institutions: the universities, the Federal Health Authorities, the army. Although Hunziker and Bayard were only country doctors, their work was at the top of the agenda. Other possible experiments were discussed, such as intestinal disinfection against imagined goitre microbes, but Bayard’s sensational trials were the focus of attention. The attendees fiercely disagreed about the reason the salt worked, but the evidence that it did seemed irrefutable. How could it be put into practice? Bayard believed that iodised salt should be compulsory; others thought that citizens should choose for themselves whether to use it. Some advocated a clandestine programme, in which iodine would be secretly added to the salt supply, to be revealed only when its positive effects had become evident. There was another complication: in a tradition that went back to the Middle Ages, each of the 25 Swiss cantons held monopoly rights on the sale of salt within its borders. Even if iodisation were to be imposed, it could not be done at federal level: the Swiss people would have to be convinced the salt was safe, canton by canton – a ‘Sisyphean task’, as Bayard later wrote.

One man at the meeting was sure it could be done. Hans Eggenberger was the chief doctor at the hospital in Herisau, the tiny capital of the sparsely populated canton of Appenzell Ausserrhoden. Unlike Bayard, Eggenberger had no doubts about Hunziker’s theory. The previous May, he had proposed salt iodisation to the canton’s health authority, only to be told, in the recollection of his then assistant, that ‘the people will never, ever permit themselves to accept something like that.’ Then and now, Appenzellers are famed throughout Switzerland for resisting change, but Eggenberger took a different view of his fellow citizens. Returning to Herisau three days after the commission met, he announced an addition to the programme of light entertainment at the town cinema – a lecture on iodised salt. Perhaps it was curiosity, or the colour slides, or the reputation of the charismatic 40-year-old doctor, but the cinema was packed.

Goitre was embarrassing, ugly and a subject for humour, so Eggenberger began his presentation with the image of the Madonna from Albrecht Dürer’s Dresden Altarpiece: unimpeachable, unmockable and exhibiting, he claimed, an obvious goitre. Speaking in the local Swiss-German dialect, he filled his talk with jokes and tugs on the emotions. He called iodised salt ‘whole salt’, in an echo of ‘whole milk’ and ‘wholemeal’, to make it sound natural and healthy. And he began a petition – a request that the cantonal government ‘take responsibility for the production of whole salt, support it financially and make it accessible to the public wherever salt is sold’. In Switzerland’s system of direct democracy, petitions have weight; in Appenzell Ausserrhoden, as in other cantons, authorities are constitutionally bound to review them and respond without delay. In pursuit of signatures, Eggenberger embarked on a breakneck tour of evening lectures, commandeering an ambulance to visit all fifteen communities in the canton in just three weeks. In five days alone, he gathered more than three thousand signatures. On 20 February, the cantonal government granted permission for production. Two days later, just one month after the Goitre Commission met, ‘whole salt’ went on sale in Appenzell Ausserrhoden. An entire canton had iodised salt: not by diktat, but by popular demand.

In June, the Goitre Commission met again. Before it lay a report on the history of using iodine to treat goitre by Professor Fritz de Quervain, the country’s leading authority on thyroid disorders. De Quervain was unconvinced by Hunziker’s unproven theory and wary of Eggenberger’s propaganda. His mentor and predecessor at the Bern Inselspital, the Nobel prizewinner Theodor Kocher, had, before his death five years earlier, publicly insisted that goitre prophylaxis should be undertaken only once its mechanism of action was proven. Yet De Quervain’s report set out the case for iodised salt: he was ready to give iodine to an entire country, without understanding how it worked. It was not a calm meeting. There were accusations of poor scientific practice, and allegations of corruption. The men knew they were on the verge of a historic decision, one that might liberate the country, or kill innocent people and destroy trust in the medical profession.

On 24 June, they formally recommended iodised salt to the cantons. Nothing like this had ever been done before, anywhere in the world: it was the first food fortification programme; the first attempt by a government to improve the lives of an entire population by adding a chemical to its food supply. In November 1922, the first batches were delivered. Within a year, iodised salt was on sale in seventeen cantons. By the end of the decade, it was available nationwide. And so – as in a fairy tale – the ‘national evil’ was banished from the land. By 1930, wherever the salt was used, goitre had all but disappeared. The rate of deaf-mute births fell fivefold in just eight years, from one in six hundred, to one in three thousand. Across the country, schools for deaf-mute children shut down. Since 1930, not a single baby has been born in Switzerland with congenital iodine deficiency syndrome.

It was a sensation. ‘Switzerland – free of goitre!’ the front page of the Basler Nachrichten announced in February 1922, days after the first Goitre Commission. ‘Unless all the signs prove deceptive, Switzerland today stands at the gates of a goitre-free future.’ The syndicated piece praised Hunziker and Eggenberger ‘as benefactors of humanity and heralds of a new era of healthcare’.

So why isn’t this story more familiar? Why has the achievement of these pioneers been forgotten, the evidence languishing in a dusty archive? On 20 July 1922, less than a month after the recommendation by the Goitre Commission, an unusually long leading article appeared in the Swiss Medical Weekly. It began: ‘If one looks through medical journals, political dailies, newspapers ... one might come to believe that, next to Einstein’s Theory of Relativity, the iodine treatment of goitre is the most important discovery of the last decades, and that ... a “goitreless” golden age has arrived.’ What followed was an astonishing attack on the Goitre Commission. Its author, Dr Eugen Bircher, son of Heinrich Bircher and his successor as chief surgeon at the cantonal hospital in Aarau, was a member of the commission, and had voted in favour of iodised salt. Yet now he raged against the ‘downright careless – not to say criminal – praise of iodine’. Insisting without any basis on the risk of the Jod-Basedow effect, Bircher failed to address the success of Bayard’s trial. One explanation for his vitriol is that in 1918, when Bayard began his experiments, Bircher launched Strumaval, an expensive, eight-day goitre treatment, which was still available when his article appeared but whose future seemed unsure.

Bircher was an influential man in 1920s Switzerland. Tall and domineering, he was a senior figure in the army, and the founder, in 1919, of the Swiss Fatherland Association, a far-right militia with links to the government and fascist groups abroad. He was the subject of scandal in 1924, when he was alleged to have given funding to Hitler in the months of hyperinflation before the Munich Putsch (German intelligence services have a record of a meeting; Swiss intelligence services do not). Hunziker, Bayard and Eggenberger had no attachment to a university or institution, but Bircher became the editor of the Swiss Medical Weekly in 1926. During the 1930s and 1940s, he occupied an ever increasing number of senior positions in the Swiss industrial, political, medical and military establishment. His opposition to iodised salt was fixed and unchanging, long after its effects were essentially beyond dispute. Until his death in 1956, annual sales of iodised salt in Aargau, the fourth-largest canton, Bircher’s home and the centre of his power, amounted to less than 10 per cent of all salt sold there. In 1931, by which time goitre had virtually disappeared among Swiss young people, 95 per cent of the schoolchildren in Aarau still had swollen thyroids.

By the time of Bircher’s death, three decades had elapsed since the headlines of 1922. A generation had died, taking with it the memory of the way life had been. In 1927, Bruno Galli-Valerio, a member of the Goitre Commission, in a speech in Valais, railed against the ‘absurd idea, sadly so widespread, that goitre and cretinism bring shame to a country, and that they must therefore be ignored’. Yet the shame and the silence were widespread. A year later, Eggenberger noted how ‘hastily people forget past plagues’.

Eggenberger died in a climbing accident in 1946, Bayard of cancer in 1957. Hunziker outlived Switzerland’s last cretin, dying in 1982, at the age of 102. None of them could have achieved the breakthrough alone. Hunziker was a visionary, with a theory so compelling it could not be ignored; Bayard, the scientist, showed the salt would work for entire towns; Eggenberger was an activist, able to convince the cautious Swiss to embrace innovation. Yet they remain unknown, while other Swiss members of their generation are household names: Hermann Rorschach, of the inkblot test, was a colleague of Eggenberger’s in Herisau; Albert Einstein went to the same school as Eugen Bircher; Max Bircher-Benner (no relation) lives on through his muesli. Carl Jung documented the strange depression that struck his mother when the family moved to Laufen – a village that, as Heinrich Bircher’s survey shows, was badly afflicted by goitre.

In 1990, Hans Bürgi, another enterprising Swiss medic, published a paper in English on the forgotten iodine pioneers. That year, iodised salt was used in less than 20 per cent of households worldwide, and a global campaign by the WHO and Unicef was set in motion. Today, iodised salt is used by more than 88 per cent of the world’s population. Internationally, it is regarded as one of the most successful public health measures ever devised. Yet in today’s prosperous and healthy Switzerland the tale seems more fantastical than ever: an evil vanquished so completely it has been all but forgotten.