Her father was a physician who came from a pioneer family in Indiana and her mother was born at a mission house to Mohegan Native Americans in New England.

After several years of teaching, Parsons left the school to attend summer session at a teachers’ college in Pittsburg, Kansas.

[3] After another brief teaching job in Oklahoma, Parsons met Abby Marlatt, head of the Home Economics department at the University of Wisconsin-Madison, at a dinner party in 1913.

Marlatt offered her an assistant job at the University of Wisconsin-Madison where Parsons was intended to be the “bridge between science and home economics”.

[4] In 1917, McCollum moved to head the biochemistry department at the newly established Johns Hopkins School of Hygiene and Public Health, where Parsons chose to follow.

By putting rats on an anti-scorbutic diet and then feeding their livers to guinea pigs suffering from scurvy, Parsons found that the diet cured guinea pigs of their scurvy, suggesting that there was an anti-scorbutic substance, which we now know as vitamin C, that was synthesized in the rats’ livers.

[5] After three years at Johns Hopkins, Parsons was offered a faculty position as an assistant professor at the University of Wisconsin-Madison and she returned to the department of Home Economics in 1920.

Around 1927, Parsons went to obtain her Ph.D. under the direction of Lafayette Mendel, a biochemical nutritionist working out of the Yale Physiological Chemistry Laboratory.

[6] She would take these results back with her to the University of Wisconsin-Madison and continue her research on what she termed “egg white injury” in her own lab.

[3] There, she was able to expand work done during her doctoral period and perform experiments critical to the discovery of biotin and avidin, as well thiamine depletion by yeast.

Parsons had noticed during her time at Yale that rats fed only raw egg-white as their protein diet developed unfavorable physiological effects such as severe dermatitis and neurological dysfunction.

A series of further experiments in 1933 proved that the anti-vitamin responsible for egg white injury was a protein that could be destroyed during peptic digestion or through exposure to hydrochloric acid.

[9] Although ultimately unable to chemically identify the protective factor, Parsons' early work on the subject was crucial to the later identification of biotin by Paul Gyorgy in 1940.

Some of her colleagues were not as fortunate - in her oral history Parsons recalls some of their research being suppressed by the larger yeast companies and their papers cancelled for publication.