METABOLIC ASPECTS OF ACUTE STARVATION BODY COMPOSITION CHANGES

Body composition changes were observed in six healthy, adult males 21 to 52 years of age, while fasting for 10 days. Fluid was available ad libitum. The mean loss in body weight 7.30 kg was densitometrically partitioned into a 3.6 kg loss of fat and a 3.7 kg loss in the fat free body mass, which included a loss of 0.86 kg of dry protein. The USAMRNL fat predicting nomogram described fat losses adequately however, urinary potassium and creatinine excretion, or potassium-40 counting, exceeded densitometric estimates of the dry protein compartment by 13 and 22, respectively. The triceps and scapula skinfolds demonstrated the greatest decrease 24.1 and 21.6 while extremity girths decreased from 9.8 to 3.2 with the circumferences of the waist and buttocks diminishing by 5.8. Blood, plasma, and red blood cell volumes were significantly lowered during the fast in accordance with the severe hypohydration that was exhibited. No sequelae were noted during and after 40 days of rehabilitation when body weight was virtually restored to control levels. Use of D2O as a tracer to demonstrate total body water appeared to be inapplicable during the starvation phase of the study.