From an endocrinological aspect, metabolic changes of humoral factors were examined in a female patient deprived of food for 18 days. On admission, serum acetoacetate (AcAc) and 3-hydroxybutyrate (3-OHB) levels markedly increased. The serum free triiodothyronine (T3) level decreased, whereas serum thyroxine (T4) concentrations were within normal range. Diurnal variations of serum cortisol levels were not observed. At day six after admission, the effects of intravenously administered thyrotropin releasing hormone (TRH) on pituitary thyroid stimulating hormone (TSH) was suppressed, whereas growth hormone (GH) was hyper-responsive. Re-feeding gradually normalized the decreased free T3 level following the reduction of serum ketone bodies. The diurnal rhythmicity of cortisol secretion was restored. At day 17, the TSH response to TRH was restored, while the GH hyperreaction was attenuated. The present case provided evidence that starvation elicits lowered TSH response and GH hypersecretion to intravenously administered TRH, and distorts diurnal rhythmicity of adrenal cortisol secretion in a healthy subject without any psychogenic disorders.