From Napoleonic Wars to Modern Medicine: How Iodine Saves Millions of Lives Every Year

Napoleon

From Napoleonic Wars to Modern Medicine: How Iodine Saves Millions of Lives Every Year

Wars have often accelerated innovation. World War I, for example, brought not only tanks, chemical weapons, and helmets but also advances in battlefield medicine—blood transfusions, wound sterilization, and surgical techniques. Similarly, during the Napoleonic Wars in the early 19th century, another breakthrough emerged—one that would ultimately save millions of lives annually: the discovery of iodine.

The Napoleonic Shortage

At the height of Napoleon’s campaigns, France faced a shortage of gunpowder due to a lack of potassium nitrate, a key ingredient. To compensate, French chemists experimented with alternative methods, including extracting nitrate from seaweed. Among them was Bernard Courtois, a Dijon-born chemist already known for his role in developing morphine.

In 1811, while processing seaweed with sulfuric acid, Courtois accidentally spilled excess acid onto the remains. To his surprise, a thick violet vapor emerged and condensed into shiny black crystals. Intrigued, Courtois suspected he had uncovered a new element.

From Curiosity to Breakthrough

Lacking resources to continue his research, Courtois shared his findings with fellow chemists. Soon, the work was taken up by Joseph Louis Gay-Lussac and Humphry Davy, who confirmed the discovery of a new element. They named it iodine, derived from the Greek word “ioeides,” meaning violet.

While Courtois never profited from his discovery—he died in poverty in 1838—the element he stumbled upon would become indispensable.

Iodine’s Lasting Impact

Today, iodine is a vital component in medicine, agriculture, and industry. Its most life-saving role lies in treating thyroid disorders, such as goiter and hypothyroidism, which once plagued millions worldwide. The introduction of iodine supplements and iodized salt has prevented countless deaths and improved public health on a global scale.

What began as a wartime necessity turned into a medical revolution. Thanks to a chain of accidents and curiosity during Napoleon’s wars, iodine continues to protect and save lives more than two centuries later.