This year’s Nobel Prize for Physiology and Medicine awarded to three scientists for their discovery of molecular mechanisms controlling circadian rhythms has reiterated the importance of sleep in our lives.
Jeffrey Hall, Michael Rosbash and Michael Young who won the award explained how plants, animals and human beings are regulated by chronobiology, or biological clocks, that synchronise bodily rhythms with the Earth’s revolutions. Several phenomena, from the pre-dawn crowing roosters to the movement of plant leaves towards light, are regulated by circadian rhythms. In fact, the biological clock anticipates an organism’s activities through a 24-hour cycle and dispatches hormones accordingly to regulate activities like sleeping, waking and eating – activities that are essential to maintain health.
The human biological clock is a mesh of nerve cells found in the brain region known as hypothalamus. In principle, the clock is tuned to the rhythm of earth’s day-night cycle that humans got used to throughout evolution. The amount of exposure to light determines the secretion of a hormone called melatonin, which in turn determines our sleep-wake cycle.
But every individual has different circadian behaviour. Some people are naturally early birds, exhibiting the chronotype – behaviour due to underlying circadian rhythms – of morningness. Others prefer to stay up late, exhibiting the chronotype eveningness. However, underlying circadian rhythms do not adapt easily to changing environments and having schedules that do not fit one’s chronotype can be detrimental to one’s health.
If sleeplessness continues, people are at heightened risks of getting one or more diseases. Lack of sleep reduces immunity. It also creates imbalances in hunger-and-satisfaction chemicals, which in turn increases the risk of gaining weight that leads to obesity, type 2 diabetes and cardiovascular diseases. Insomnia diminishes psychological well-being and heightens the risk of becoming anxious and depressed and reduces libido.
So, how well do Indians sleep? Turns out, not so well.
Most people around the world accept the norm that the adult body needs eight hours of sleep per day. The National Sleep Foundation in the United States recommends that adults between the ages of 18 and 64 get between seven and nine hours of sleep per day.
By these accepted standards, Indians are among the most sleep deprived people.
Technology devices company Fitbit conducted a survey of sleep habits in 18 countries that showed Indians get an average of six hours and 55 minutes of sleep per day. Only the Japanese slept less with an average of six hours and 35 minutes per day. New Zealanders seemed to clock the most amount of sleep on average at seven hours and 25 minutes.
Another survey by electronics company Philips of 5,600 Indians and found that 93% of them were sleep deprived. About 74% of respondents said that they woke up between one and three times during the night. Many reported how the lack of sleep took a toll on their work – 58% felt that their work suffered and many even fell asleep at work while 11% took leave from work due to lack of sleep.
There are no long-term studies with large numbers of trial subjects on insomnia in India. However, the available academic research on Indians tells that people of different age groups stay awake in the night for various reasons. There are also studies that indicate differences in sleep habits and quality by gender.
In a 2011 study, scientists at the National Institute of Mental Health and Neurosciences in Bengaluru studied sleep patterns of 1,050 healthy attendants of patients at the institute. About 18% of the respondents reported having insomnia. About 40% of the respondents reported sleep-related disorders.
Of the people with insomnia, 18% reported difficulty falling asleep and another 18% reported difficulty in maintaining sleep once they are asleep.
In another study conducted by researchers at Vardhman Mahavir Medical College and Safdarjang Hospital in New Delhi in collaboration with the National Institute of Medical Statistics, 59% among 1,240 elderly people reported to have difficulty in both falling asleep and maintaining it. Sleeplessness, especially among the elderly, can often be due to illness or caused by medication for illness.
But even Indian children have trouble sleeping. A National Institute of Medical Statistics study showed that about 17% of 2,475 school children from Delhi who took part in a survey had insomnia.
Women are more likely to suffer from insomnia than men. New mothers are prone to insomnia for they have to have disturbed sleep in order to feed their babies. Between 40% and 60% of menopausal women report sleep disruptions because of menopausal transitions in their bodies.
Blame it on BPOs
A large factor in sleep disruptions is due to social jetlag – the difference between biological and social times. This occurs when people with morning chronotypes have to work or conduct social activities that run late into the day and when people with evening chronotypes have to wake up early. Social jet-lag is more pronounced among many Indians who work in call centres and have to stay awake through the night when they would normally be asleep.
An analysis of studies conducted among call-centre employees in India reveals that the majority of workers on night shifts are unable to sleep adequately during daytime. The analysis pointed out that 40% of employees across the IT enabled services had sleep disorders, among which, 83% were workers at call-centres.
In a study conducted in the Delhi-National Capital Region, researchers analysed sleep patterns of 181 call centre employees and the same number of people who were not employed in call centres. They found that 51% of call centre employees were found to be sleepier as compared to 20% among other workers. The same pattern is repeated in findings of studies from other parts of the country.
Like most other parts of the work, sleep deprivation among Indians is also caused by the presence of 24/7 television channels with news and movies, smartphones with several addictive games and applications and by the constant interruptions of social media.
Repaying the sleep debt
The lack of sleep over periods of time accumulates as a sleep debt that can lead to chronic ill-health. A good night’s sleep helps the body to repair itself while the brain rewinds and sorts the day’s experiences as memories.
There are ways to improve our sleep behavior. Long working and studying hours are part of the Indian cultural legacy, but they are not scientifically correlated with high productivity at work or exams. So, it is important to maintain strict work and home hours and better organise activities at work and home. Avoiding smoking, alcohol and binge eating while engaging in more physical and relaxing activities and maintaining sleep diaries may also help pare down that sleep debt.