Background
: What changes are developed by insufficinet nutritional intake or total fasting was considered as good clues for health maintenance of starving and treatment of overnutrition. But research into starvation can be problematic from ethical point of view. So, in most studies, animals or only a few volunteers were included as study subjects. This created difficulties in overcoming the limitations of animal experiments and too small sample size to generalize the study results.

Methods : Fasting was continued for a period of 5 days in 201 health people voluntarily from sociopolitical reason. During this time no food was eaten. But water and NaCl was allowed ad libitum. We, under thier agreement, observed changes in body mass, blood pressure, pulse rate, blood cell count, and blood chemistry. Using a self-administered questionnaire, we checked any symptoms which were aggravated by or newly developed during fasting.

Results : The most commonly checked symptom was 'weakness in hands and feet', followed by 'difficulty in going upstaris and downstairs', 'dizziness', and 'foul odor from the mouth'. Total body weight loss was 2.7kg on the average. Systolic and diastolic blood pressure decreased significantly only in men. WBC count, phosphorus, BUN, glucose, and amylase decreased significantly. Platelet count, creatinine kinase, S-GOT, S-GPT, uric aicd, cholesterol, and triglyceride increased significantly. Direct bilitubin increased in all people, but statistical significance was found only in men. Total calcium level increased in all people but statistical significance was found only in women.

Conclusion : 5-day fasitng resulted in more weight loss than expected from the compensation mechanism for calory deficiency. And fasting produced not only aggravation and new development of symptoms, but also changes in blood pressure, blood cell count, and blood chemistry.