Elmer McCollum was born on a farm near Fort Scott, Kansas, where he spent his first seventeen years. Money was scarce and the rural community's single school was rarely in operation. But the young Kansan was bright, energetic, and determined to get an education. By moonlighting at numerous jobs, he worked his way, first through high school, then through the University of Kansas, graduating in 1903, and finally through Yale University, where he earned his doctorate in 1906.

Throughout his academic career, McCollum's first love was always organic chemistry. Shortly after graduation, however, he was offered a position at the University of Wisconsin as an instructor in biochemistry (then known as agricultural chemistry). With no better job offers in sight, he decided to accept--a decision that was to alter his life. In 1907, when McCollum arrived at the University's Agricultural Experiment Station, a research study was already in progress. The study...