...constituents of food, ie re-purified fat, protein, carbohydrate, mineral salts, and water. He concluded that 'a natural food such as milk must therefore contain...of other and unknown substances essential to life'. Similar conclusions were reached by various other workers, of whom the most notable were Socin (1891)...

...and minerals — could not survive, while mice fed whole milk behaved normally. They concluded that "a natural food such as milk must therefore contain...these known principal ingredients small quantities of unknown substances essential to life." However, these conclusions were not pursued to determine the...

...mixture died, while the mice given whole milk lived normal lives. As a result, Lunin concluded that "a natural food such as milk must therefore contain,...these known principal ingredients, small quantities of unknown substances essential to life." In 1905, William Fletcher discovered that consuming unpolished...