effect of religious fasting on intraocular pressure in healthy individuals

purpose: to evaluate the effects of diurnal fasting during ramadan on intraocular pressure (iop) in healthy subjects. methods: the study was conducted on healthy male volunteer less than 40 years of age without ocular or systemic diseases who were on religious fasting during ramadan, 2004. intraocular pressure were measured at 9 am and 1, 5, and 7 pm in 2nd and 4th weeks of ramadan and also one month after ramadan, except for the 7 pm measurement. results: twenty-eight eyes of 14 men were evaluated. duration of fasting was between 12-13 hours. mean age was 31.9±4.4 years. mean weight in the 4th week decreased about 1 kg in comparison to the 2nd week of fasting (p=0.05) and increased about 1.5 kg one month after ramadan in comparison to the 4th week of fasting (p= 0.008). mean iop at 9 am and 1 pm significantly decreased in the 4th week compared to the 2nd week (1.1 and 1.5 mmhg, respectively). mean iop significantly increased one month after ramadan compared to the 4th week of ramadan (1.4 and 2.1 mmhg, respectively). mean iop at 5 pm one month after ramadan had a significant increase of 1.6 and 1.8 mmhg compared to the 2nd and 4th weeks of ramadan, respectively. mean iop at 7 pm (after breaking the fast) decreased 0.5 and 0.6 mmhg in comparison to 5 pm (before the time of breaking the fast) in the 2nd and 4th weeks of ramadan, respectively. conclusion: intraocular pressures changes due to fasting in healthy person are not considerable. evaluating intraocular pressure changes in cases with glaucoma with enough sample size is recommended.