BACKGROUND: Orthodox Christian believers fast abstaining from meat, eggs, dairy products or even fish and oil in certain days of the fasting period, three times a year.AIM: The present study aimed to investigate the impact of a 48-day fast before Easter in blood count parameters, coagulation and antioxidant status.MATERIAL AND METHODS: A total of 35 healthy volunteers, 19-66 years old, were included in the study. White blood cells (WBC), lymphocytes (Lymph), granulocytes (Gran), haemoglobin (Hb), hematocrit (Ht), red blood cells (RBC), mean erythrocyte volume (MCV), platelets (Plt), were measured. Blood coagulation parameters, such as PT, aPTT, fibrinogen concentration, factor VII activity were also determined, and INR (PTsample/PTcontrol) and aPTT ratio (aPTTsample/aPTTcontrol) were calculated. Total antioxidant capacity (TAC) was assayed.RESULTS: Levels of all parameters remained within normal. By the end of the fasting period, lymphocytes and TAC levels were significantly increased (p = 0.011), whereas all the other parameters, except fibrinogen, were significantly decreased.CONCLUSION: Orthodox Christian fast impairs all haematological and coagulation parameters and seems to be beneficial in the body antioxidant protection.