Nidrayattam Sukham Duhkham Pustih Karsyam Balabalam
Vrsata Klibata Jnanamajnanam Jvitam Na Ca
Happiness, misery, nourishment, emaciation, strength, weakness,
virility, sterility, knowledge, ignorance, life
and death – all these occur depending on proper or improper sleep.
Nidra or deep, restful sleep is one of the body’s most potent, natural tool of restoration. And yet, most people don’t get enough of it. Especially in India. Surveys reveal that Indians are among the most sleep deprived people in the world.
This is worrying given that even one night of insufficient sleep can cause mood swings, difficulty in retaining information and reduce efficiency. And chronic sleep deprivation, according to research, can lead to a higher risk of serious problems such as diabetes, obesity, high blood pressure and heart diseases among others. However, studies have found that over-sleeping is not the solution either, as that too can contribute to poor health. On average 7 to 8 hours of sleep is recommended. But a study also reveals that participants who slept well for 6 hours were as functional as participants who had 8 hours of disturbed sleep. So, the right amount of sleep time is important. But the quality of the sleep experienced may have an equally vital contribution.
Typically, one sleep cycle (usually over 24 hours) has two phases – Non-Rapid Eye Movement (NREM) sleep is the first. Rapid Eye Movement (REM) sleep is the second phase. NREM sleep is associated with stable brain waves and decrease in body temperature. Dreams and eye movements rarely occur in this phase. NREM sleep consists of:
Stage 1: This is the lightest stage of the first sleep cycle. Muscles begin to relax; eye movements and brain activity slows down.
Stage 2: The heart rate begins to slow down along with the brain waves.
Stage 3: This is known as the slow wave sleep or deep sleep. It occurs roughly 30 to 45 minutes into the sleep cycle. This is when the body recuperates. Cell regeneration, secretion of hormones for growth and development, muscle tissue repair, restoration of energy – these are some of the processes that take place during this stage.
Different individuals can have varying circadian rhythms. Some people have the chronotype of morningness – early birds. Others have the chronotype of eveningness – night owls. Chronotypes determine the time of the day when we feel most productive.
The next phase is REM sleep. During this phase the brain signals sent to the spinal cord result in the body going into a lockdown so that our bodies are immobilized. The mind becomes active. This is when we dream most vividly. REM sleep stimulates areas of the brain that enhance our cognitive abilities. People who get enough REM sleep display sharper memory and learning abilities along with a balanced mood.
Interestingly our traditional wisdom has always emphasised the importance of sleeping well. Charaka Samhita, a 2000-year-old Ayurvedic treatise, prescribed methods to reduce sleeplessness and make sleep healing. Much of the advice is about setting a routine prior to bedtime. This can include a good body massage, warm bath, a meal of rice with curd, consuming a glass of milk or a glass of wine, surrounding yourself with pleasant smell and sound, applying soothing ointment on eyes and comfortable bedding. Surprisingly, this wisdom is still relevant and incidentally, many of these methods are also advocated by western scientists in their discussions of sleeplessness.
As a result of evolution all human beings have a biological clock that is attuned to the day-night cycle. Based on this internal rhythm our bodies are programmed to secrete Melatonin, the sleep-inducing hormone. This internal body clock, which regulates Melatonin production, is our circadian rhythm. More commonly, this is the sleep-wakefulness cycle of our body over the course of 24 hours. Typically, it is attuned to the sun cycle. However, different individuals can have varying circadian rhythms. Some people have the chronotype of morningness – early birds. Others have the chronotype of eveningness – night owls. Chronotypes determine the time of the day when we feel most productive. Identifying our circadian rhythm and attuning our schedules with it could mean better sleep and more efficiency. Circadian rhythms are fascinating, and their importance and intricacies are still being studied. The 2017 Nobel prize for Physiology and Medicine was awarded to Jeffrey Hall, Michael Rosbash and Michael Young for work on the circadian rhythm.
Urban lifestyles impact these natural rhythms. Because of electricity we are no longer dependent upon the sun cycle. Electronic devices can also interfere with the circadian cycle and impact the way we sleep in different ways. One is just the sheer entertainment and engagement offered by them. But typically, they can also impact our sleep because of the lights emitted; from the screen colour to the blinking blue or red light emitted. For e.g., blue light pushes the mind into active mode. Blue light can also interfere with secretion of melatonin, and hence with the circadian rhythm. Therefore, it is a good idea to go off electronic devices well before bedtime and ideally, not place them in your line of sight when you are going off to sleep.
Clearly adequate, restful sleep is vital for our health and happiness. We should take the time to adopt the simple routines and practices that can make our sleep truly restorative.