At that time Dam was studying the synthesis of cholesterol in chickens. Dam found a hemorrhagic disease in chicks that were fed a diet from which all lipids had been removed.
Dam hypothesized that an unidentified lipid factor had been removed from the chicks’ feed. It was the only substance capable of halting a hemorrhagic disease in which blood does not coagulate.
Hemorrhages were prevented when unextracted fish meal was included in the diet.
In 1930 Horvath first mentioned that an unknown factor was necessary for blood clotting in chicken.
Following further research Dam called it ‘koagulations vitamin’ or ‘vitamin K’ and the letter that he assigned it is still used today.
Dam later succeeded in isolating the agent from alfafa and identifying it, for which he received the Nobel Prize for physiology and medicine.
The structure was determined to be 2-methyl-3-phytyl-1,4-naphthoquinone (vitamin K1).
After the initial discovery of vitamin K, Edward Doisy determined that the main source of vitamin K was through the diet, particular from green vegetable and fish meal.
Discovery of vitamin K
