The First B Vitamin Discovered Was Thiamine (B1): A History
The first B vitamin discovered was thiamine, now known as vitamin B1. Researchers identified it in the early 20th century while searching for the cause of beriberi, a debilitating disease that had plagued populations in Asia for centuries.
The Search for the Cause of Beriberi
In the late 1800s, beriberi was a major health problem, particularly in regions where polished white rice was a dietary staple. Patients suffered from nerve damage, muscle wasting, heart failure, and paralysis. The prevailing medical theory blamed an infectious agent or a toxin.
A Dutch physician named Christiaan Eijkman, working in the Dutch East Indies (modern-day Indonesia), noticed something unusual. Chickens fed leftover hospital rice (polished white rice) developed symptoms similar to beriberi. Chickens fed unpolished brown rice stayed healthy. Eijkman initially thought a toxin in the white rice caused the disease. It was his colleague, Gerrit Grijns, who correctly proposed that the rice lacked a necessary nutrient.
Eijkman’s Chicken Experiment
Eijkman’s experiment was simple but powerful. He divided the chickens into two groups:
| Group | Diet | Outcome |
|---|---|---|
| Group A | Polished white rice | Developed beriberi-like symptoms |
| Group B | Unpolished brown rice | Remained healthy |
When he switched the diets, the sick chickens recovered after eating brown rice. This provided the first strong evidence that a missing dietary factor, not a poison or germ, caused beriberi. Eijkman later shared the Nobel Prize in Physiology or Medicine in 1929 for this work NIH.
Isolating the Active Substance
The next step was to isolate and identify the specific substance in the rice bran that prevented beriberi. This task took several decades. In the 1910s, Polish biochemist Casimir Funk coined the term “vitamine” for these essential compounds, believing they were all amines. He was wrong about the amine part, but the name stuck.
The actual isolation of thiamine was achieved in 1926 by Dutch chemists Barend Coenraad Petrus Jansen and Willem Frederik Donath. They extracted a small amount of a crystalline substance from rice bran. This substance was extremely potent: tiny doses cured beriberi in animals. They called it “aneurin” (for antineuritic vitamin). Its chemical name, thiamine, reflects its sulfur (thio-) and amine (-amine) content Encyclopædia Britannica.
Why Thiamine Matters
Thiamine acts as a coenzyme in the body. It is essential for converting carbohydrates into energy and for the normal function of nerves and muscles. Without it, cells cannot produce enough energy, and nerve tissues are particularly vulnerable.
Beriberi: Wet and Dry
Beriberi presents in two main forms, both caused by thiamine deficiency:
- Wet beriberi affects the cardiovascular system, causing rapid heart rate, swelling in the legs, and shortness of breath. Fluid buildup can lead to heart failure.
- Dry beriberi damages the peripheral nerves, leading to muscle weakness, tingling or numbness in the hands and feet, and difficulty walking.
Severe, prolonged deficiency can also cause Wernicke-Korsakoff syndrome, a brain disorder common in people with chronic alcohol use disorder.
Food Sources and Requirements
Thiamine is found in many foods, but the richest sources include whole grains, pork, fish, legumes, and fortified cereals. Because thiamine is water-soluble, the body does not store it in large amounts. People need a regular intake. A simple example: a serving of fortified breakfast cereal provides roughly 1.0 to 1.5 mg of thiamine, covering an adult’s daily need in one meal.
The Legacy of the First Discovery
The identification of thiamine as the first B vitamin opened the door to finding the rest of the B-complex family. Within a few decades, researchers discovered riboflavin (B2), niacin (B3), pyridoxine (B6), cobalamin (B12), and others. Each discovery followed a similar pattern: a deficiency disease was identified, and the missing nutrient was found in whole foods.
This work also changed how people thought about food. It moved nutrition from a vague concept of “eating well” to a precise science of specific chemical compounds. The polishing of rice, once seen as a refinement, was recognized as a process that stripped away essential nutrients. This led to food fortification programs, such as adding thiamine to white flour and rice, which largely eliminated beriberi in developed countries.
Today, thiamine deficiency is rare in populations with access to a varied diet. It remains a risk for people with alcohol dependence, those on restrictive diets, or patients with certain medical conditions that impair absorption.
Key Takeaways
- The first B vitamin discovered was thiamine (vitamin B1), identified through research on beriberi in the early 1900s.
- Christiaan Eijkman’s chicken experiments showed that polished white rice lacked a substance found in brown rice that prevented the disease.
- Thiamine is essential for carbohydrate metabolism and nerve function; deficiency causes beriberi and Wernicke-Korsakoff syndrome.
- Good dietary sources include whole grains, pork, fish, legumes, and fortified cereals.
