"To gain insight into the physiology of starvation, in 1944 [Ancel] Keys carried out a starvation study with 36 conscientious objectors as test subjects in the Minnesota Starvation Experiment. At the time, conscientious objectors were being placed in virtual concentration camps, with a few functioning like the Civilian Public Service, so that recruiting them would prove easier than seeking out volunteers in the general population.^[14][17] The original pool of 400 responders was reduced to 36 selectees, of whom 32 would go on to complete the study.^[23] The main focus of the study was threefold: set a metabolic baseline for three months, study the physical and mental effects of starvation on the volunteers for six months, and then study the physical and mental effects of different refeeding protocols on them for three months.^[14] The participants would first be placed on the three month baseline diet of 3200 calories after which their calories were reduced to 1800 calories/day while expending 3000 calories in activities such as walking. The final three months were a refeeding period where the volunteers were divided into four groups, each receiving a different caloric intake.^[14]

The war came to an end before the final results of the study could be published, but Keys sent his findings to various international relief agencies throughout Europe^[3]and, by 1950, he completed publication of his two-volume 1385-page Biology of Human Starvation." (Wikipedia article on Ancel Keys, accessed 01-2017).