Is Ramadan fasting related to health outcomes? A review on the related evidence

BACKGROUND Fasting during Ramadan is an Islamic rule. Although previous review studies have assessed the impact of Ramadan on cardiovascular risk factors, athlete performance, diabetes and transplantation, in this study we have appraised some on these reviews by focusing on limitations and also, we have reviewed more recently published study and several recent studies, which are not reviewed till now. MATERIALS AND METHODS In this article, we reviewed recently conducted studies in regarding the impact of Ramadan fasting on weight, lipid profile, diabetes, immune system and gestation. MEDLINE (http://www.pubmed.com) was searched by using "Ramadan" as keyword and the most recent articles in mentioned topics since 2009 until February 2014 were selected. RESULTS Although weight has been decreased during Ramadan in the most studies, weight regain is prevalent during the following months. Meta-analysis of pre-Ramadan lipid profile in comparison to post-Ramadan values had been showed that total cholesterol and triglyceride were decreased in men and high-density lipoprotein was increased among women. In regarding diabetes and fasting, diabetic patients should be aware that medical, nutritional and physical activity consulting is necessary for individuals with diabetes who want to fast during Ramadan. Although published studies show that Ramadan fasting had no serious adverse effect on offspring, it is strongly recommended that pregnant women avoid fasting because of the limitations of studies. The effect of fasting during Ramadan on the immune system is favorable. Ramadan fasting has no impact on kidney function and urine component. CONCLUSION Studies showed that Ramadan fasting has health protective effects. More precise studies should be conducted for more reliable conclusion.