The most immediate metric to is serum glucose.
To establish a clear, evidence-based framework for determining the onset, progression, and severity of starvation in human subjects, differentiating it from simple caloric restriction or eating disorders without metabolic crisis. -termine starvy-
To properly , clinicians look for the cessation of exogenous fuel (food) and the body’s switch to endogenous fuel (body fat and muscle). The most immediate metric to is serum glucose