Response to starvation before and after a jejuno-ileal bypass operation for morbid obesity

A greater metabolic response developed during a seven day starvation in two morbidly obese patients three months after a 90 per cent jejuno-ileal bypass operation when compared with a similar fast before operation. There was a greater degree of ketosis, a decreased urinary urea excretion and an earlier utilization of ketone bodies. These changes suggest a metabolic adaptation of the body to the semistarvation state caused by the operation with a more rapid utilization of adipose tissue as a fuel and a sparing of lean body mass.