They started out eating a normal 3,200 calories per day for three months to set a baseline. Then, during the six-month test phase, they took in, on average, less than half that amount—1,570 calories per day. The men needed to lose a certain amount of weight every week, and the scientists found that it became harder and harder to get them to lose weight. (Remember this.) As a result, the researchers had to keep reducing the food rations. Some of the subjects ended up with portions of less than a thousand calories a day. For the better part of six months.
