Once upon a time, a terrible disease called kakke ravaged the aristocracy in Japan. A patient could recover, or could die of the disease. No one could figure out what caused it, or why it was mostly restricted to the upper class. They tried herbal medicines and other traditional cures, and doctors even recommended that suffers get out of Edo (Tokyo) because the city was killing them. And that actually helped in a lot of cases. But what was killing people was their expensive diet of mainly white polished rice. It turned out that kakke was not a communicable disease, but a nutritional deficiency.
Gleaming white rice was a status symbol—it was expensive and laborious to husk, hull, polish, and wash. In Japan, the poor ate brown rice, or other carbohydrates such as sweet potatoes or barley. The rich ate polished white rice, often to the exclusion of other foods.
This was a problem. Removing the outer layers of a grain of rice also removes one vital nutrient: thiamine, or vitamin B-1. Without thiamine, animals and humans develop kakke, now known in English as beriberi. But for too long, the cause of the condition remained unknown.
Things got worse. In the late 19th century, machines were developed to hull and polish rice, and the Japanese navy began serving it to sailors, since it had less weight and could be stored longer than brown rice. Dr. Takaki Kanehiro stepped in to find out what was causing the illness, and what could be done about it. Read the story of his efforts at Atlas Obscura.
(Image credit: Wellcome Collection)