Many people recognize Ramadan as a month to stay awake at night and sleep during the day. This lifestyle however, varies from one Muslim country to another, where the customs prevailing in the society affect the pattern of a person's life during the holy month.

The sudden change of eating habits and timing, from day to night (fasting during daytime and eating at night) are accompanied by some physiological changes in the body.

FAQs:

Does fasting during the holy month of Ramadan lead to excessive sleepiness?

To answer this question we need to have further discussions. We need to know the exact difference between the effect of fasting on body’s physiology, and the effect of change in lifestyle during the holy month and consequently its effect on the sleep.

How is the sleep affected by the lifestyle change during the holy month?

Many people associate Ramadan with late night meals, which change the lifestyle of the community. During Ramadan work starts late, markets open in the evening, and the social meets with relatives and friends increase. As a result, one faces acute lack in sleep during the night. All this causes laziness, sleepiness, and mood swings during the day.

In one of the studies based on a set of students (sample size - 56), we found that there is no difference in the duration of sleep during Ramadan and Sha'ban months, i.e. they slept for the same no. of hours a day during Sha'ban and the initial three weeks of Ramadan.

The difference however, was in the sleeping and waking up time. The students' sleeping time changed from 11:30 pm to about 3:00 am, in the first week of Ramadan. The waking up time was gradually delayed from 6:30 am to 8:45 am within the first week of Ramadan and reached 9:15 am in the third week.

It was observed that the students complained of sleepiness during the day in Ramadan, in spite of sleeping for the same duration. This may be due to the sudden change in waking up and sleeping schedule, the potential physiological changes of fasting such as alterations in melatonin secretion, or the possibility of some psychiatric factors or mood swings that accompany fasting and affect the sleep. The earlier possibilities are still theoretical and unconfirmed.

Are there any physiological changes that affect the sleep during fasting?

There are some factors that may affect the sleep physiology during fasting. The abrupt change in the eating and sleeping time may result in increased metabolism in the night, which leads to an increase in the body temperature at night. Usually the body temperature decreases at the onset of sleep and that helps the body to sleep easily. However, eating at night in Ramadan increases the body temperature leading to excessive activity and lack of sleep at night. This is followed by lower body temperature during the daytime due to fasting, leading one to feel sleepy. Simply put the body’s biological clock changes. This was one of the theories supported by actual study and talks about the relationship between fasting and sleep.

However, the above-mentioned theory did not hold true in the case of the research carried out recently on a set of healthy volunteers, where we did not report any change in body’s usual temperature between Sha'ban and Ramadan. Also, we did not observe any significant change in the circadian rhythm of melatonin during the holy month. In addition to that, lab studies and observations suggested that there was no change in the quality of sleep during Ramadan. It was also noted a person who got adequate sleep during the fast did not feel sleepy.

The earlier observation mentioned that the people who fast, were gaining weight in the holy month as a result of the excessive eating during night.

Therefore, based on available evidence from research we can conclude that fasting neither affects the quality of sleep nor does it cause excessive sleepiness during the day. The sleep changes at Ramadan could be a result of the change in the lifestyle during the fasting month. Based on this, we advise the people who are fasting, to be regular in the lifestyle and avoid the sudden change in waking up and sleep time, as the daytime sleep is not adequate.

Consequently, the reader is recommended to get sufficient sleep at night and sleep in the day for a short time. In addition, excessive eating at night, particularly prior to sleep leads to sleep disorders and an increase of the acid influx into esophagus, which affects the sleep quality.

The earlier information is critical in case of children; hence, parents should ensure that their children get adequate sleep during Ramadan.

Ahmed BaHammam, FACP, FCCP
Professor of Medicine
Director, University Sleep Disorders Center
College ofMedicine, King Saud University