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Introduction

One of the fundamental rituals of Islam is fasting during the month of Ramadan. This month varies across the years and is decided by the lunar calendar. Devotees are supposed to fast from dawn to sunset every day of the month. Fasting means abstaining from eating, drinking, and taking medications as well as intravenous fluids and nutrients. During the month of Ramadan, meals are limited to two: one before sunrise and one shortly after sunset. Hence, meals are exclusively nocturnal and less frequent, with the total amount of food intake being generally less . Consequently, the total body weight slightly decreases during this month. This has been attributed to a decrease in fluid intake as the total amount of water and vegetable intake has been reported to be less . As a result of this intermittent fasting, there are numerous physiologic and chronobiologic changes. Several studies have been undertaken to investigate the effects of fasting in healthy subjects, the results of which are controversial mainly due to variations in the protocols used, differences in nutritional customs and habits, and the seasonal occurrence of the Ramadan month. The hematologic, cardiac, circadian, and hormonal changes have been elucidated in the literature . There have been reports showing a 24-hour mean decrease in the glucose level during Ramadan in comparison to the control day before fasting . On the other hand, studies of lipid blood level showed an increase in total cholesterol and a decrease in low-density lipoprotein and low-density lipoprotein–high-density lipoprotein ratio . Concerning serum protein levels, an increase in total proteins was demonstrated, with the most important change being the serum uric acid urea and serum osmolarity . These changes were mainly attributed to dehydration. The decrease in water intake has also been reflected in a decrease in the 24-hour urine collection. The urinary output has been shown to decrease and the urinary osmolarity to increase with the effect being more pronounced during the third week of the month .

Based on a PubMed search, no study has looked at the effect of fasting on voice in males. Voice has been shown to be affected to various degrees by both systemic and local dehydration. However, there are controversies in the literature regarding the extent of these effects . Most of the studies with human subjects included a small number of candidates and had a limited number of fasting hours.

The authors of this manuscript have previously investigated the effect of fasting on voice in women . Women were chosen initially because they are more prone to certain voice disorders than men. This has been attributed to the presence of less absorbing fluid in their vocal ligaments compared to men. More so there are other differences in the microstructure of the vocal fold in women compared to men. The distribution of hormonal receptors is denser in males, and the lamina propria is larger and contains 3 times more hyaluronic acid .

The presence of significant vocal changes while fasting in the female group has prompted this investigation of males while fasting. The purpose was to study the effects on voice of fasting for 12 to 14 hours using a self-reported evaluation, acoustic analyses, and laryngeal stroboscopic examination. The hypothesis was that fasting will result in an increase in phonatory effort, a high prevalence of vocal fatigue, and possibly a decrease in the maximum phonation time. The findings of this study are pertinent to the correlation between water intake and vocal complaints.