Allah
(all glory be to Him) tells us in the Holy Quran about Ramadan that, “(He
wants you) to complete the prescribed period (of fasting), and to glorify Him in
that He has guided you; and perchance ye shall be grateful.” (2:185)
Many
benefits, in addition to the spiritual, result from completing this prescribed
period of fasting. This article attempts to explain those related to our
biological rhythms.
The
Stages of Sleep
The
background activity of the brain is called the electroencephalogram (EEG) and
can be recorded by the use of scalp electrodes. The dominant frequency and
amplitude characteristic of the surface EEG varies with states of arousal.
A
person goes through five stages while going to sleep.
Calm
wakefulness is accompanied by alpha waves 8-12 Hz (cycles per second) and low
voltage fast activity of mixed frequency. This is called stage one.
Alpha waves disappear when we open our eyes.
As
sleep deepens into stage two, bursts of 12-14 Hz (sleep spindles) and
high amplitude slow waves appear.
The
deep sleep of stages three and four is featured by an increasing
proportion of high voltage slow activity. Breathing is regular in
slow-wave sleep or non-REM (Rapid Eye Movements) sleep.
Delta
activity (very slow waves, 0.5-4 Hz, high amplitude) is unusual in a normal
record and accompanies deep sleep i.e. stages three and four sleep.
After
about 70 minutes or so mostly spent in stages three and four, the first REM
period occurs, usually heralded by an increase in body movements, and a
shift in the EEG pattern from stage four to stage two. These rapid low-voltage
irregular waves resemble those seen in alert humans; sleep, however, is not
interrupted. This is called stage 5 or REM sleep, when the EEG activity
gets desynchronised. There is marked muscle atonia despite the rapid eye
movements in REM sleep, and the breathing is irregular.
Theta
activity with a pattern of large regular waves occurs in normal children and
is briefly seen in stage one sleep and also in REM sleep.
Non-REM
(NREM) sleep passes through stages one and two, and spends 60-70 minutes in
stages three and four. Sleep then lightens and a REM period follows. This cycle
is repeated three or four times per night, at intervals of about 90 minutes
throughout the night, depending on the length of sleep. REM sleep occupies 25%
of total sleeping time.
When
the eyes are opened, the alpha rhythm is replaced by fast irregular low voltage
activity with no dominant frequency, called the alpha block. Any form of
sensory stimulation or mental concentration such as solving arithmetic problems
could produce this break-up of the alpha rhythm. This replacement of the regular
alpha rhythm with irregular low voltage activity is called “desynchronisation”.
Fasting
Positively Affects Sleep
During
the first few hours of an Islamic fast, the EEG is normal. However, the
frequency of the alpha rhythm is decreased by a low blood glucose level.
This may happen at the end of the fasting day towards evening when the blood
sugar is low.
Fasting
improves the quality and intensifies the depth of sleep, a matter of particular
importance to the aged who have much less stage three and four sleep (deep
sleep). The processes of repair of the body and of the brain take place
during sleep. Two hours of sleep during the month of Ramadan are more
satisfying and refreshing than more hours of sleep otherwise!
REM
sleep and dreaming are closely associated. Dreaming may be necessary to
maintain health, but prolonged REM deprivation has no adverse psychological
effects. Dreaming sleep occupies 50% of the sleep cycle in infants and
decreases with age. Brain synthetic processes occur in deep sleep; brain
protein molecules are synthesized in the brain during deep sleep or used in REM
sleep in restoring cerebral function. Fasting significantly increases deep
sleep and leads to a fall in REM sleeping time or dreaming time, and also
accelerates synthesis of memory molecules.
Fasting
and the Circadian Rhythm
The
period of the circadian pace-maker in humans is 24 hours 11 minutes.
Hormonal secretion is frequently characterised by rhythmic fluctuations which
may be regular or irregular in periodicity. The period of regular
oscillation may be as short as a few minutes or as long as a year.
The
body timing system that drives circadian rhythms is exposed to external factors
ranging from the imposed activity-rest cycle, the natural light-dark cycle, and
social activities outside the workplace.
There
are biological pacemakers or oscillators within the body with time-keeping
capacity which synchronise with the external environmental cycles such as light.
Environmental cues that synchronize biological pacemakers are called
“zeitgebers” (from the German “time-givers”), and the process of
re-setting the pacemaker is called re-synchronization.
The
light/dark cycle is a potent zeitgeber for circadian rhythm but daily cycles in
temperature, food availability, social interaction (such as congregational
prayers) and even electro-magnetic field strength synchronize circadian rhythm
in certain species. Because of recurring cycles of light, temperature and
food availability, organisms evolved endogeous rhythms of metabolism and
behavior providing response to specific environmental cycles. Many
biological rhythms reflect the period of one of four environmental cycles:
cycles of the tide, of day and night, of moon phase and of seasons.
Muslims
who have been fasting regularly since childhood, have been exposed to different
sleep/wake and light/darkness cycles on a daily basis in one annual lunar month.
Hence, it may be easier for such persons to synchronize their circadian,
circalunar and circannual biological rhythms under difficult conditions.
Fasting,
Jet Lag and Shift Work
International
travel across time zones produces symptoms of jet lag such as sleep
disturbances, gastro-intestinal disorders, decreased alterness, fatigue and lack
of concentration and motivation.
Factors
contributing to symptoms of jet lag are (1) external desynchronisaion due to
immediate differences between body time and local time at the end of the flight. (2) internal desynchronisation due to the fact that different circadian rhythms
in the body re-synchronise at different rates, and during the re-synchronisation
period, these rhythms will be out of phase with one another.
General
symptoms arising from desynchronisation include tiredness during the day and
disturbed sleep and reaction time. The severity of these adverse effects
and therefore the time required for re-synchronisation depends on the ability to
pre-set the bodily rhythms prior to flying, the number of time zones crossed,
the direction of flight, age, social interaction and activity. NASA
estimates that it takes one day for every time zone crossed to regain normal
rhythm and energy levels. A 6-hour time-difference thus needs 6 days to
get back to normal.
Rapid
adaptation to a new zone can be facilitated by maximising exposure to zeitgebers
for the new cycle e.g. changing to meal times and sleep times appropriate to the
new time zone. Maximising social contact and exposure to natural lgihting
will result in faster resynchronisation than staying at home in a hotel and
eating and sleeping without regard to local time. There are widesperead
individual viariations in the rapidity of resynchronisation.
Muslims
who fast regularly and who have experienced disturbed wakefulness/sleep cycles
on a daily lunar annual basis, can adapt themselves much faster to different
time zones during international travel and do not suffer from the ill effects of
jet lag. Moreover, the social contact during the Tarawih congregational
prayer and the other social-cum–spiritual activities act as zeitgebers which
regulate any desynchronised biological rhythm.
Shift
workers also experience similar symptoms as jet lag, especially
gastro-intestinal, cardiovascular, and sleep disorders and also reproductive
dysfunctions in women. The inverted schedule of sleeping and waking also results
in diminshed alterness and performance during night-time work with attendant
increase in the number of fatigue-related accidents during night time shift
hours. Normally, a period of three weeks is required for re-synchronisation
among shift workers, and as the fasting Muslim atunes himself to
resynchronization processes during the space of just over four weeks in Ramadan,
his health problems as a shift worker would be negligible, as his
synchronization processes would be more rapid, whether during Ramadan or at any
other time.
It
is also a common observation that as soon as Ramadan is over, normal circadian
rhythms are established in the fasted Muslims with such great rapidity as to be
at par with pre-Ramadan levels on the first day of Shawwal, i.e. Eid-ul-Fitr.
Fasting
and Encephalins
During
fasting, certain endogenous, narcotic-like substances known as opioids (or
endorphins) are released into the body. They have a tranquilizing effect
as well as an elating effect on the mind. These are also probably
responsible for prevention of psychosomatic diseases. The opioids have
several effects, including slowing down metabolism to conserve energy.
Another effect of opioids may be that, although they produce elation as well as
intense hunger, they do not drive the person to eat with sheer gluttony.
Muslims
in Ramadan experience an ability to intensely focus their minds on meditation,
Quranic recitation and prayers. This spiritual gain during the Holy Month
is despite the fact that normal sleep/waking cycles are somewhat disturbed and
despite a long day of fasting. Perhaps now we have a closer idea as to the
science of this miraculous process.
Dr.
Ebrahim Kazim is a medical doctor and the founder and director of the Islamic Academy in Trinidad. The above article was excerpted with permission of the author from his book “Further Essays on Islamic Topics”.
