Recommended Guidelines for Designing and Interpreting Ramadan Fasting Studies in Medical Research

Ramadan fasting requires significant alterations to routine life, which can affect body homeostasis and metabolism. In spite of several studies conducted on the effects of Ramadan fasting on health and various disorders, there is an absence of comprehensive and reliable results due to heterogeneous methodologies and procedures (which is sometimes inevitable). Based on preliminary studies on this issue, this paper suggests a checklist containing the important factors for designing, interpreting, and comparing the results of Ramadan fasting studies. Circadian rhythm, season/latitude sensitivity, serum osmolality, and lifestyle alterations (e.g., dietary intakes, physical activity, sleep quality and duration, smoking) may be of great importance in Ramadan fasting studies. In addition, the number and pattern of fasting days (consecutive or alternate days) must be considered with regard to gender. Appropriate timepoints for blood/urine sampling might vary depending on cases.