Thank You World War One for the Sun lamp

Berlin Children Suffering from Rickets, Around 1918

In the winter of 1918, it's estimated that half of all children in Berlin were suffering from rickets—a condition whereby bones become soft and deformed. At the time, the exact cause was not known, although it was associated with poverty.

A pediatrician in the city, a former medic in German Army – Kurt Huldschinsky – noticed that his patients were very pale. He decided to conduct an experiment on four of them, including one known today only as Arthur, who was three years old. He put the four of them under mercury-quartz lamps which emitted ultraviolet light.

Huldschinsky may have been inspired by he earlier work of Danish-Faroese-Icelandic physician, Niels Ryberg Finsen (1860–1904), who received the 1903 Nobel Prize for Medicine and Physiology, for his pioneering work on the therapeutic and physiological effects of light treatment from artificial light sources.

Dr. Huldschinsky

As the treatment continued, Huldschinsky noticed that the bones of his young patients were getting stronger. In May 1919, when the sun of summer arrived, he had them sit on the terrace in the sun. The results of his experiment, when published, were greeted with great enthusiasm. Children around Germany were brought before the lights. In Dresden, the child welfare services had the city's street lights dismantled to be used for treating children.

Researchers later found that Vitamin D is necessary to build up the bones with calcium and that this process is triggered by ultraviolet light. The undernourishment brought on by war produced the knowledge to cure the ailment.  

Dr. Huldschinsky was nominated for a Nobel Prize for his groundbreaking work. By the 1920s and '30s, light therapy was all the rage and manufacturers in Europe and America were making shiny new sun lamps that cast ultraviolet rays—and that also came to be used for cosmetic tanning.

Of course, the use of ultraviolet light is now treated with much greater caution: overexposure to ultraviolet light over a long period of time can lead to melanoma and other skin cancers.

By the way, Dr. Huldschinsky was Jewish and eventually needed to flee Germany. He emigrated to Egypt, where he was allowed to practice, passing away in 1940.

Source: BBC; NIH: Circulating Now, 20 December 2016