Backgrounds & Purpose : Ramadan fasting is a unique cycle in which man should avoid eating and drinking. In many conditions such as plasma LDL and IGF-1 concentration, effects of prolonged & Ramadan fasting are different. This study was conducted to determine the effect of Ramadan fasting on LDL & IGF-1 and their correlations.

Material & Methods: 132 healthy adult volunteers (60 women, 72 men) took part in this quasi-experimental study. All participants fasted for at least 25 days in the lunar month of Ramadan.The amount of serum IGF-1 was measured by radioimmunoassay 1 week before and on the 14^th and 28^th days of Ramadan. Statistical analysis with ANOVA, the Student's paired t-test, and Pearson's regression analysis were all carried out in this respect.

Results : No significant change in the serum concentration of IGF-1 was found in men, women or the group during this study ,but serum level of LDL was decreased significantly.

Conclusions: Ramadan fasting has no effect on plasma IGF-1, but it decreases plasma LDL significantly