Eijkman's Chickens: How Beriberi Led to Vitamins

In the late 1880s, a young Dutch physician in Java was looking for the germ that caused beriberi, a disease that weakened the legs, swelled the body, and killed people in prisons, barracks, and asylums. He found no germ. What he found, by accident, was that chickens in his laboratory developed a beriberi-like paralysis when they were fed polished white rice and got better when they were fed whole-grain rice. Christiaan Eijkman's chickens led, over about four decades, to the idea of the vitamin, to the isolation of thiamine (vitamin B1), and to a Nobel Prize in 1929.

Java in the 1880s: a disease that looked infectious

Beriberi was not new. Chinese medical texts from the third century onward describe a condition called "foot qi" that resembles it, and the disease became more common as polished white rice spread. In Japan, the habit of eating polished rice grew during the Edo period and then nationwide in the Meiji era, and beriberi followed it (Wikipedia summary of beriberi history). In the Dutch East Indies in the 1880s, it hit institutions with the most uniform diets, such as prisons, asylums, and military barracks.

Two features of the disease made it look infectious. It clustered in closed institutions, and it spread through a population over time. By then, the germ theory of disease had a series of triumphs behind it, and the logic seemed straightforward: a disease that clusters and spreads has a microbe behind it. The theory, as developed by Louis Pasteur and Robert Koch, is described in germ theory: Pasteur and Koch's microbial discovery, and Koch's role is covered in a profile of Robert Koch. Eijkman was working inside that framework.

Eijkman had earned his doctorate in 1883 and went to the Dutch East Indies the same year as a medical officer. He caught malaria in 1885 and went back to Europe on sick leave, where he worked in laboratories in Amsterdam and Berlin. He then joined a government commission led by the Dutch scientists Cornelis Pekelharing and Cornelis Winkler to investigate beriberi, as an assistant. The commission found no causative organism. Pekelharing and Winkler were recalled in 1887, and their temporary laboratory in Batavia (now Jakarta) was made permanent, together with a medical school for Javanese students, the Sekolah Dokter Djawa. Eijkman became the first director of the school and, from January 15, 1888 to March 4, 1896, directed the laboratory (Wikipedia biography of Eijkman).

Dates in the early part of the story differ from one account to another. The James Lind Library has Eijkman sent to the Indies in 1886, other accounts have him back in Java in 1887, and the key chicken observation is dated to 1889 in some histories and to about 1890 in others. This article gives the dates as the sources do and notes where they diverge.

The chicken accident

The animals came first, and the idea came later. Eijkman wanted an animal model of beriberi, one he could infect on purpose and study under controlled conditions. At first, he fed chickens material from patients and inmates, expecting that they would get sick if the disease was infectious. Nothing happened for a long time. Then, in 1889 by one account, his chickens began to stagger, developed a paralysis of the legs that resembled beriberi, and then recovered (James Lind Library).

The first reaction was to suspect the germ explanation. A biographical article in PubMed Central describes how Eijkman tried several variations. Chickens given bacteria did not develop the disease, so he suspected a longer incubation time. Chickens he had infected and those he left unexposed all became ill. Birds kept in separate cages still got sick, and so did a second group moved to a new location. In each case, the results made no sense for an infectious disease, because the controls got sick too (Eijkman biography, PubMed Central).

The detective work that solved this was mundane. Eijkman learned that for a few weeks the chickens' feed had been changed from unpolished rice to polished rice, and then changed back. Accounts differ on who made the switch. The James Lind Library says one of Eijkman's servants did, and other histories say a cook. In every version, the chickens recovered when the unpolished rice returned. Eijkman then reversed the experiment on purpose. He fed polished rice and the chickens got sick, and he fed unpolished rice and they recovered. The condition was named "polyneuritis gallinarum," a nerve disease of chickens, and it became the animal model he had been seeking. The Nobel award ceremony speech of 1929 also ties the hens' illness to their diet and describes Eijkman's later finding that rice bran protected against the disease (Nobel Prize, award ceremony speech).

What is polished rice?

The distinction matters for the rest of the story. A grain of rice, as harvested, has an outer husk, then a thin brown layer of bran and germ, and then the white starchy endosperm inside. Polishing, also called milling, removes the husk and bran, leaving the white endosperm. The result stores longer, cooks faster, and looks cleaner, which is why it was prized. It also loses most of the nutrients that live in the bran, a fact nobody knew in 1889 because nobody knew that such nutrients existed.

A helpful way to think about it is a recipe with a missing ingredient. A cook who follows every step but leaves out the baking powder gets a cake that does not rise, and nothing in the visible steps explains why. The failure is in what was subtracted, which is harder to notice than what was added. The chickens ate plenty of rice and plenty of calories. They were starving for something that had been milled away.

The prison rice study

Chickens are not people, and Eijkman needed to see whether the same pattern held in human beings. The test came from a different observer. Adolphe Vorderman, a Dutch physician working for the colonial government, surveyed prisons across Java and Madoera and compared the rate of beriberi with the type of rice each prison served. The study was published in 1897 (Vorderman, 1897, James Lind Library).

The design of Vorderman's survey was careful for its time. A rice expert classified the rice samples without knowing where they had come from, labeling them only by letters or numbers and trying to identify whether each came from Saigon, Rangoon, or Siam. The categories of prison, by rice type, were fixed before the beriberi statistics were handed to the doctors, so the people counting disease did not know which prisons had been placed in which category. The special aim of the visit was kept secret from the suppliers, to prevent them from changing the rice they provided. Those steps are the early forms of blinding, a safeguard that modern trials rely on (James Lind Library). The general power of that idea is explored in why randomized trials are powerful.

Accounts of the results differ in their details. The Nobel ceremony speech of 1929 gives a ratio, saying beriberi was about 300 times as common in prisons that used polished rice as in prisons that used unpolished rice. Other popular accounts quote different raw counts that could not be traced to Vorderman's original report, so this article does not repeat them. The safest statement is the qualitative one: in Vorderman's survey, the disease was far more common where polished rice was the staple.

Takaki and the Japanese navy

Vorderman's study was not the first dietary evidence. In the mid-1880s, the Japanese naval surgeon Takaki Kanehiro compared ships' diets. From 1878 to 1881, sailors in the Japanese Navy averaged four illnesses a year, and 35% of the illnesses were beriberi. On an 1882 training voyage, 169 cases and 25 deaths occurred among 376 men, while a control ship with a more varied diet had 14 cases and no deaths. By 1887, beriberi had been eliminated on Navy ships (Wikipedia summary of beriberi history).

Takaki's work was a natural experiment on a large scale, and it had a policy consequence. It also had an unfortunate counterpart. The Japanese Army, influenced by a group led by the physician and writer Mori Ōgai, disputed the deficiency theory until 1926. During that period, over 300,000 Japanese soldiers contracted beriberi and over 27,000 died, according to the same summary. The episode shows how a sound result can fail to persuade an institution that has committed to an alternative explanation.

The step Eijkman missed

Eijkman reasoned like a bacteriologist. His chickens got sick on polished rice and recovered on unpolished rice, so something in the rice was involved. The simplest explanation within his framework was a poison. According to several histories, he proposed that polished white rice contained a toxin that was not present in unpolished brown rice (Hektoen International).

His own writings, as described in one biography, also mention an "anti-beriberi factor" missing from polished rice, so the accounts of what Eijkman himself concluded are not entirely consistent. What is not in dispute is that the deficiency interpretation was stated most clearly by his successor, Gerrit Grijns.

Grijns, born in 1865, was Eijkman's assistant from 1892 to 1894 and took over the research in Batavia in 1896. Over about three years of feeding experiments with chickens, he tested whether the disease depended on carbohydrates, proteins, fats, or salts in the diet, and found that it did not. He judged a bacterial infection unlikely. In 1901 he published his conclusion: whole-grain rice contains an unidentified protective substance that the nervous system needs, and the disease results from its absence when the husk is removed. He called the idea "partial hunger," and he is credited with identifying the diseases of deficiency (Resource, Wageningen University).

The difference between the two readings is the difference between a poison and a missing part. Under the poison model, the cure is to remove or neutralize the poison. Under the deficiency model, the cure is to restore what was removed. They predict different things. A poison should be present in some foods and absent from others, and a deficiency should be curable with tiny amounts of a specific substance. Experiments could tell them apart, and they did.

Fletcher in Kuala Lumpur

A further test came in 1907, when the British physician William Fletcher reported an experiment at a lunatic asylum in Kuala Lumpur, Malaya. Inmates were assigned to one of two types of rice, and the results were published in The Lancet (volume 1, pages 1776 to 1779). The James Lind Library describes it as a rigorous experiment that mimicked several features of a modern randomized trial. Fletcher concluded that the polished rice was, in his words, "either directly or indirectly, a cause of beri-beri," and he offered three possible explanations: a toxin in rice, a deficiency in rice, or rice that was insufficiently nutritious, making people more prone to infection (James Lind Library).

The experiment sits alongside another famous step in the history of controlled comparison, the one described in the Lind scurvy trial, in which a naval surgeon in 1747 gave different treatments to different pairs of sailors and watched the outcome. A modern reader should also notice what these studies would not pass today. Assigning patients to a diet expected to cause disease would not be approved by an ethics board, and the same is true of many of the experiments in the complete guide to landmark science experiments. The history of the vitamins is also a history of research that was done under standards that no longer apply.

From "accessory factors" to the vitamin concept

By the first decade of the twentieth century, several lines of evidence pointed in the same direction. The following table collects the key steps. Where sources disagree on a year, the table shows the range.

Year	Person	Contribution
mid-1880s	Takaki Kanehiro	Dietary change eliminates beriberi from Japanese naval ships by 1887
about 1889	Christiaan Eijkman	Chickens fed polished rice develop polyneuritis; recover on unpolished rice
1897	Adolphe Vorderman	Prison survey with blinded rice classification links polished rice to beriberi
1901	Gerrit Grijns	Concludes that whole rice contains an unidentified protective substance; deficiency, not poison
1906	Frederick Gowland Hopkins	Proposes that tiny "accessory food factors" are essential to health
1907	William Fletcher	Reports Kuala Lumpur asylum experiment on rice types
1910	Umetaro Suzuki	Extracts a water-soluble complex from rice bran that cures beriberi, called "aberic acid"
1912	Casimir Funk	Coins "vitamine" in a review of deficiency diseases
1926	Barend Jansen and Willem Donath	Isolate and crystallize the anti-beriberi substance in Batavia
1936	Robert R. Williams and J. K. Cline	Report the synthesis of vitamin B1 (thiamine)

Hopkins's contribution, per one account, dates to 1906. He proposed that minute "accessory food factors" were essential for health. Funk's 1912 paper, "The Etiology of the Deficiency Diseases," appeared in the Journal of State Medicine (volume 20, pages 341 to 368) and discussed beriberi, polyneuritis in birds, scurvy, pellagra, and others. Funk argued that these diseases could be prevented by adding certain substances to the diet, and he called them "vitamines," from "vital" plus "amine." The final "e" was dropped later, when it became clear that vitamins need not be amines (Funk, 1912, scanned paper).

The word has a slightly comic history, because the name encoded a guess. Funk believed that the substances were amines. Most turned out not to be. The word stuck anyway, which is one more demonstration that a name can outlive the idea that produced it. The concept, though, that a handful of tiny substances are essential to life and that their absence causes specific diseases, was right.

The same logic applies to the disease that Lind studied. Scurvy, described in the article on the Lind scurvy trial, is a deficiency of vitamin C. Beriberi is a deficiency of thiamine. Both stories show a common pattern in medicine: a disease that looks infectious, or that is blamed on a poison, turns out to come from something missing. The chemist Linus Pauling later became one of the most famous advocates of vitamin C, a reminder that the vitamin era never stopped producing strong claims that needed testing.

Isolating the factor

Naming a missing substance is not the same as finding it. The anti-beriberi factor was present in rice bran in tiny amounts, mixed with many other compounds. Isolating it took a generation.

In 1926, Barend Jansen and Willem Donath, working in Batavia in the same laboratory tradition that Eijkman had started, isolated and crystallized a substance from rice bran extracts that cured polyneuritis in pigeons. They named it aneurin, for "antineuritic vitamin." Their 1926 report, "On the isolation of the anti-beri-beri vitamin," is cited in Semba's history of the discovery (Semba, "The discovery of thiamin," Annals of Nutrition and Metabolism).

Robert R. Williams, an American chemist who worked at Bell Telephone Laboratories, then determined the structure of the vitamin and made it from scratch. He named it thiamin because of its sulfur-containing thiazole ring and because it is an essential amine. The synthesis was reported with J. K. Cline in the Journal of the American Chemical Society in 1936 (volume 58, pages 1504 to 1505). Accounts place the work between 1933 and 1936, and the synthesis was reported in 1936.

Synthesis mattered for practical reasons. Once the substance could be made in a factory, it could be added to food, and a population's intake no longer depended on what its rice looked like. Adding a missing nutrient to a staple food became a widely used public health approach. This article describes the history of the discovery and does not offer medical or dietary advice.

The Nobel Prize and the people left out

In 1929, the Nobel Prize in Physiology or Medicine went to Eijkman and Hopkins, shared, for the discovery of the antineuritic vitamin and of the growth-stimulating vitamins, respectively. Eijkman was by then too ill to travel to Stockholm to receive it in person. He died on November 5, 1930, in Utrecht.

The prize has been criticized for the person it omitted. Grijns had been nominated alongside Eijkman in 1926 and 1927, but he was not nominated in 1929. The Wageningen article attributes the oversight partly to limited awareness of his work and notes that he published in Dutch rather than in international journals; it also says Eijkman did not give him due credit in his acceptance speech. Eijkman was nominated nine times in total (Resource, Wageningen University). The comparison is uncomfortable. The man who observed the effect shared the prize, and the man who interpreted it correctly did not.

The point is not to diminish Eijkman. His chickens gave the field its model, and without an animal that reproduced the disease in a few weeks, the search for the vitamin would have depended on slow observations of human populations. But the usual shorthand that Eijkman "discovered vitamins" compresses a collective achievement, with contributions from Takaki, Vorderman, Grijns, Fletcher, Hopkins, Funk, Jansen, Donath, and Williams, into a single name. Most scientific discoveries, on close inspection, look like that.

What the experiments got wrong

An honest account of the chicken experiments should list what they did not show, and what Eijkman himself got wrong.

• The germ search was a dead end. The program that brought Eijkman to Java was an attempt to find a pathogen. It failed, and the failure was informative.
• The first interpretation was a toxin. Per several histories, Eijkman reasoned that polished rice contained a poison that unpolished rice lacked. The deficiency interpretation was supplied by Grijns and later work.
• The chicken result was an accident, not a design. The diet switch happened because of a cook's decision. Eijkman recognized the clue and followed it up, which is a skill, but it was not a planned test. Accidents of this kind are common in the history of discovery, as in the Fleming penicillin discovery.
• An animal is a stand-in. The polyneuritis of chickens resembles human beriberi but is not the same illness, and the prison surveys were needed to show that humans behave similarly.
• Observational data have limits. Vorderman's survey and Takaki's naval comparison are comparisons between groups that differ in many ways. The blinding steps improved them, but they were not randomized, and that is why Fletcher's allocation of asylum inmates to rice types was significant, however ethically fraught.
• Parts of the story are uncertain. The year of the key observation, the number of chickens, and the exact figures from the prison survey all vary between accounts. A reader should keep two facts in mind together. The conclusion, that a missing nutrient causes beriberi and that thiamine cures it, is firmly established. The path to it was messier and more contested than the tidy version told in textbooks.

What thiamine does, and where beriberi still appears

Thiamine is a vitamin that the body cannot make and must obtain from food. In its active form it serves as a helper (a cofactor) for enzymes that break down carbohydrates to release energy. Nerves and the heart use a lot of energy and depend on a steady supply, which is why a shortage shows up in those tissues first. (The energy pathway is covered in the Krebs cycle explained, and the nerve signaling that depends on it is covered in how the nervous system works.)

Beriberi has several forms. The wet form affects the heart and circulation, causing a fast heart rate, breathlessness, and leg swelling. The dry form affects the nerves and causes numbness, confusion, weakness in the legs, and pain. An infantile form usually appears at two to six months of age in babies whose mothers have a low thiamine intake. The body has limited reserves, and thiamine has a half-life of about 17 days, so it can be depleted when demand exceeds intake (Wikipedia summary of beriberi).

The disease has not disappeared. It is rare in most of the developed world but remains relatively common in sub-Saharan Africa. In wealthier countries, a common cause is alcohol use disorder, which reduces thiamine intake and absorption and impairs its use in the body. Wernicke encephalopathy is a thiamine-related brain condition seen mainly in this setting. Outbreaks continue to be reported in places where diets are monotonous and institutions control food, including a 1999 outbreak in a detention center in Taiwan, a 2007 outbreak in a Haitian jail linked to the washing of enriched rice, and an outbreak in the Ivory Coast in which 64% of one group of prisoners were affected. Among Chinese squid-ship workers, there were 15 deaths on 14 ships from 2013 to 2021 (Wikipedia summary of beriberi). The settings are a modern echo of the prisons and barracks of 1890s Java. Anyone concerned about a deficiency should speak with a clinician, since this article describes mechanisms and history only.

Why a chicken experiment mattered

Three lessons from the story hold beyond nutrition.

Models can come from accidents. Eijkman did not plan to feed polished rice to chickens. He noticed an unexpected result and followed it up. That depended on a controlled setting in which something odd could be seen, the kind of discipline that connects this story to older ones such as John Snow and the Broad Street pump and Semmelweis and handwashing, each of which used patterns in data to find a cause before the mechanism was known.

Absence can be a cause. Germ theory trained medicine to look for something that invades. Beriberi showed that disease can result from something that is missing, which is a harder thing to see, since there is no organism, no toxin, and no visible agent. The idea opened the door to the identification of the other vitamins and to the concept of deficiency diseases.

Theories shape what people can see. A toxin explanation and a deficiency explanation fit the same chicken data. The toxin version was more natural for a bacteriologist in the 1890s, and the deficiency version required a new way of thinking about food. It took experiments by a different researcher to make the leap. The Japanese Army's resistance to the deficiency theory until 1926 shows how long an established frame can persist.

Frequently asked questions

Q: What did Eijkman discover with his chickens? A: He found that chickens fed polished white rice developed a paralysis of the nerves resembling beriberi, and that the chickens recovered when they were fed unpolished rice. The observation showed that the disease was linked to diet, not to a germ, and it led to the concept of the vitamin.

Q: Why did Eijkman win the Nobel Prize? A: He shared the 1929 Nobel Prize in Physiology or Medicine with Frederick Gowland Hopkins. Eijkman's share recognized his discovery of the antineuritic vitamin, the dietary factor whose absence causes beriberi. He was too ill to travel to Stockholm and died in 1930.

Q: What causes beriberi? A: Beriberi is caused by a deficiency of thiamine, or vitamin B1. Historically, it appeared in populations whose diets were dominated by polished white rice. Today it also appears in people with alcohol use disorder and in some other conditions that reduce thiamine intake or absorption.

Q: Who first said beriberi was a deficiency disease? A: Gerrit Grijns, Eijkman's successor in Batavia, concluded in 1901 that whole-grain rice contains an unidentified protective substance and that the disease results from its absence. Eijkman himself is generally described as having proposed a toxin in polished rice, though accounts of his views differ.

Q: Who coined the word vitamin? A: Casimir Funk used "vitamine," from "vital" and "amine," in a 1912 review of deficiency diseases. The final "e" was dropped later, when it became clear that vitamins are not all amines.

Q: When was thiamine isolated and synthesized? A: Barend Jansen and Willem Donath isolated and crystallized the anti-beriberi substance from rice bran in Batavia in 1926. Robert R. Williams and J. K. Cline reported its chemical synthesis in 1936.

Q: Why was Grijns not awarded a Nobel Prize? A: He was nominated alongside Eijkman in 1926 and 1927 but not in 1929. A Wageningen University article attributes the oversight partly to limited awareness of his work and notes that he published in Dutch rather than in international journals. Nominations are sealed for 50 years, so more may be learned.

The takeaway

The chicken experiment is remembered as a single event, but it reads better as the first step in a relay. A physician looking for a germ found a diet effect by accident. A prison inspector showed the same pattern in thousands of people and took care to avoid bias. A successor named the missing factor. A British biochemist and a Polish-born chemist built the concept of the vitamin, and two chemists in Batavia and a third in New Jersey turned a rumor in rice bran into a molecule. The sequence took about 47 years from the chickens to the synthesis.

What it shows about method is less comfortable than the legend. The decisive clue was an accident that a well-prepared mind noticed, the first explanation was wrong, and the person who got the interpretation right was left out of the prize. But the end result held up. A disease that killed soldiers and prisoners for centuries turned out to come from something missing, and the missing thing turned out to be a molecule that could be made on demand. The story of the discovery is a reminder that the right question is sometimes not "what is in the food that harms people" but "what has been taken out."

Sources

• Wikipedia. Christiaan Eijkman (career dates and Nobel Prize)
• Wikipedia. Beriberi (history, Takaki's naval comparison, forms of the disease, modern outbreaks)
• James Lind Library. Eijkman, Vorderman and the deficiency theory of beriberi and Vorderman AG (1897)
• PubMed Central. Christiaan Eijkman (1856-1930)
• Resource, Wageningen University. Wageningen's greatest: Gerrit Grijns
• Hektoen International. Christiaan Eijkman, unpolished rice, and the discovery of vitamins
• Funk, C. (1912). The etiology of the deficiency diseases. Journal of State Medicine 20:341-368. Scanned copy
• Nobel Prize. Award ceremony speech, Physiology or Medicine 1929
• Williams, R. R., and Cline, J. K. (1936). Synthesis of vitamin B1. Journal of the American Chemical Society 58:1504-1505. See also Semba, R. D. (2012), The discovery of thiamin.