The Effect of Ramadan Fasting on Endocrine System

Document Type : Review Article


1 Department of Clinical Biochemistry, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

2 Surgical Oncology Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran


In the religion of Islam, fasting is obligatory for healthy adults during Ramadan. Millions of Muslims around the world practice fasting in this holy month which may cause different metabolic and hormonal changes due to the restrictions in regular caloric intake. This article was aimed to review some possible effects of Ramadan fasting on the endocrine system which has a great impact on physiological and cellular processes through a wide variety of hormones. Despite various studies regarding the impact of Islamic fasting on a number of hormonal values, yet there is not any obvious consensus on its impact on human health. In conclusion, this article recommended normal people to continue fasting during this holy month because despite the modifications that occur in the secretion pattern of some hormones, it causes no major alteration in the health of normal subjects; it is also effective for maintenance of remission in some diseases.


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