The effects of Islamic fasting on blood hematological-biochemical parameters

Fasting during the month of Ramadan is obligatory for healthy Muslims after the age of puberty. This paper was aimed to compare the changes in hematological and biochemical parameters before and after Ramadan.
This prospective study was performed one week before and one week after the month of Ramadan in 2015. Eighty-nine subjects (51males and 38 females) with a mean age of 34.52±9.05 were enrolled in this study. Patients with systemic disorder, special drug using, and/or a history of previous surgery were excluded. Blood samples were taken from all participants before and after Ramadan to evaluate the effects of fasting on hematological-biochemical factors. Hematological and biochemical measurements were performed on the blood samples using a KX-21N cell counter (Kobe, Japan) and Hitachi 717 analyzer (Roche, Japan), respectively.
Hematocrit, red blood cell (RBC) and Mean Red Cell Volume (MCV) decreased after Ramadan fasting (P= 0.002, P= 0.030 and P= 0.005, respectively), however mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) increased (P=0.004, P=0.002, respectively). On the other hand, no changes were seen in hemoglobin, platelets and white blood cell (WBC) after Ramadan (P=0.900, P=0.923, P=0.282, P=0.300, respectively).
In this study, fasting led to decrease in uric acid, creatinine, selenium, sodium and potassium (P=0.00, P=0.015, P=0.021, 0.007 and 0.028, respectively), however, phosphor serum increased after fasting period (P=0.032). Moreover, no changes were seen in other biochemical parameters including fast blood sugar (FBS), urea, calcium, iron, zinc, and albumin (P= 0.54, P=0.300, P=0.054, P=0.372, P=0.170, and P=0.400, respectively).
This study on healthy subjects suggests that fasting could affect some hematological-biochemical parameters but not all of them. Also, these changes in hematological-biochemical parameters were within the normal range and Ramadan fasting seems to be safe for healthy subjects.