American Journal of Applied Sciences 4 (8): 565-569, 2007 ISSN 1546-9239 © 2007 Science Publications 565 Study the Effects of Ramadan Fasting on the Serum Glucose and Lipid Profile among Healthy Jordanian Students Kamal Mohmoud Saleh Mansi Department of Biological Sciences, Al al-Bayt University Al-Mafraq – Jordan Abstract: Ramadan is the holiest month in the Islamic calendar and Muslims fast during this month. We designed this study to evaluate the effect of Ramadan fasting on plasma lipids profile and serum glucose among healthy Jordanian students. Ramadan fasting entails major changes in sleep pattern, physical activity and eating habits, which may cause changes in metabolism both in health and disease. This cohort study was performed during Ramadan in October 2006 (Islamic year 1427). The subjects were 70 healthy Jordanian students (male and female) from three Jordanian universities who fasted during Ramadan. Their mean age was 21 ±1.6 years. We evaluated some anthropometric parameters as body weight (Kg), pulse rate (per minute) and systolic and diastolic blood pressure (mmHg). All parameters at 4 week of Ramadan were significantly lower than pre-Ramadan values, 2 weeks after Ramadan fasting, body weight and other parameters had a trend to recoup to pre-Ramadan status; however, they were still lower than the pre-Ramadan values. We evaluated blood glucose, triglycerides (TG), cholesterol, low-density lipoprotein LDL), high-density lipoprotein (HDL), and Triglycerides at 1 day before, at week 1, 2, 4 of the Ramadan month and after tow weeks after the end of Ramadan. It was found that high-density lipoprotein (HDL) cholesterol increased significantly during Ramadan, which indicated positive association with pulse rate and fat intake and negative association with systolic blood pressure and weight. . The LDLc was significantly reduced at the end of fasting. A reduction in the average TC value was observed at the end of fasting but the difference was not statistically and there no significant rise in the TG and blood sugar values at the end of fasting. This study indicated that Ramadan fasting led to a decrease weight, LDLc significantly, and significant not statistically reduction in the average TC value, and significantly increasing in HDLc was noted during Ramadan. There was a non-significant rise in the TG, and blood sugar value at the end of fasting. It seems that the effect of Ramadan fasting on serum lipid levels may be closely related to the nutritional diet or biochemical response to starvation. Key words: Ramadan fasting, cholesterol, high-density lipoprotein (HDL), low density lipoprotein (LDL), triglycerides (TG) INTRODUCTION Ramadan fasting is one of the 5 pillars of Islam and one of the most significant ibadat (worships) of Islam [1] Throughout the world, millions of Muslims fast during Ramadan to fulfill this religious obligation. Because the lunar calendar determines the month of Ramadan and is about 11 days shorter than the solar year, Ramadan is not fixed to any season. The timing of daily fasting varies from country to country and with the season in which the month of Ramadan falls. Thus, depending upon the season and the geographical position of the country, the length of the fast varies from 12 to 19 hours per day [2] . During Ramadan, Muslims abstain from food and drink from dawn until sunset. Traditionally the practice is to eat 2 meals, 1 before dawn, suhore, and 1 just after sunset, iftar. Often Muslims eat a greater variety of foods in their meals during Ramadan than in other months. As a result, the Ramadan fast provides an excellent opportunity to study the effects of various diets on the human body and can serve as an excellent research model for metabolic and behavioral studies [3] . Ramadan fasting and starvation are not synonymous. Many physiological and psychological changes take place during Ramadan, most probably due to the changes in eating patterns, eating frequency and sleep patterns [4] . Some studies in the eastern Mediterranean area have indicated improved high-density lipoprotein (HDL) cholesterol during Ramadan fasting [5, 6] . Few studies have shown the