The science of sleep and the role of sleep aids

The Hindu

a day ago

Some people seem to fall asleep the moment their head touches the pillow, while others toss and turn, counting imaginary sheep or scrolling endlessly on their phone. For the latter group, a growing market of sleep aids exists from white noise machines and rain sound playlists to herbal teas, melatonin pills and age-old practices like drinking warm turmeric milk before bed. Do these sleep aids help? And what makes falling asleep so effortless for some, yet such a challenge for others?
Experts point to a complex mix of biology, lifestyle and environment.
What is sleep?
According to Sridhar R., senior consultant, Interventional Pulmonology, MGM Hospital, Chennai, sleep is broadly divided into two categories : Rapid Eye Movement (REM) sleep and Non-REM (NREM) sleep. NREM has three stages, from light sleep (N1) to deep, restorative slow-wave sleep (N3). REM, where vivid dreaming occurs, is vital for memory and emotional processing.
A typical night involves four to six sleep cycles, each lasting 70–120 minutes, moving fluidly between NREM and REM stages. While adults require 7 to 8 hours of sleep, Indu Khosla, senior consultant, Paediatric Pulmonology, Narayana Health SRCC, Mumbai, notes that newborns may sleep up to 22 hours a day, children need 9 to 12 hours, teenagers 8 to 10 hours and older adults 6 to 8 hours. Interestingly, she adds, 'Indians and Asians generally take less sleep than their Western counterparts.'
Experts explain that those who nod off quickly may simply have a robust circadian rhythm the body's internal clock and lower pre-sleep arousal. Others may benefit from optimal 'sleep hygiene': regular sleep times, low stress before bed and minimal light exposure. On the other hand, for people who lie awake, causes can range from excessive evening caffeine and screen use to underlying sleep disorders like insomnia or obstructive sleep apnea (OSA).
Sounds and habits
Auditory aids -- white noise, pink noise, rain sounds, whale calls, Indian classical ragas, even traditional conch blowing can help by masking sudden, disruptive sounds. M.S. Panduranga, senior consultant , Neurology, Dharamshila Narayana Superspeciality Hospital, explains,'The brain processes sounds even during sleep. A continuous, uniform sound acts like an acoustic blanket, reducing the chance of arousals from irregular noises.'
Pink noise, such as steady rainfall, can even synchronise brain waves and consolidate sleep. Indian classical music, says Dr. Sridhar, offers a 'structured broadband quality' that relaxes without the jarring impact of random noise. For babies, rhythmic sounds may mimic the mother's heartbeat in the womb, aiding sleep but Dr. Khosla cautions against creating long-term dependence on such aids.
Sindhu V., consultant, pulmonology, SRM Global Hospitals, Chennai explains, 'India's mix of traditional and modern habits has a clear impact on sleep'. Late-night chai -- rich in caffeine -- and prolonged screen exposure suppress melatonin, delaying sleep onset. Blue light from devices signals the brain to 'stay awake,' a problem most pronounced in urban areas.
In rural regions, sleep tends to follow the natural light cycle -- early to bed, early to rise, whereas city dwellers often push bedtimes later due to artificial lighting, socialising or work. 'Practices such as yoga, meditation and warm milk before bed, rooted in Indian tradition, can help counteract these modern disruptions,'Dr. Sindhu said.
Sleep associated health risks
Insomnia -- sleep disorder where people struggle to fall asleep, stay asleep, or both, even when they have the opportunity for a full night's rest, Obstructive sleep apnea( OSA)-- another sleep disorder where your upper airway repeatedly becomes blocked during sleep, causing pauses in breathing (apnea) or shallow breathing (hypopnea) , restless leg syndrome -- a neurological disorder that causes an irresistible urge to move the legs, often accompanied by uncomfortable sensations and narcolepsy -- a chronic neurological disorder that disrupts the brain's ability to regulate sleep-wake cycles, leading to excessive daytime sleepiness and other sleep disturbances are among India's most prevalent sleep disorders.
OSA, often linked to obesity, enlarged tonsils, craniofacial structure-- the intricate framework of the head and face, encompassing the skull, facial bones, muscles, nerves, and teeth, which develops from complex embryonic processes like neural crest cell migration disrupts deep sleep and can cause hypertension, heart disease, and memory impairment. Dr. Khosla stresses that even children especially those living with obesity, Down syndrome, or neuromuscular disorders can suffer from OSA, making timely diagnosis through sleep studies crucial.
Towards healthier sleep
While there is some evidence that herbal remedies including chamomile tea, ashwagandha, brahmi, and turmeric milk promote relaxation, self medicating with over-the-counter sleep medications can be risky. Dr. Sridhar advises professional consultation, particularly for chronic insomnia (trouble sleeping three or more nights a week for over three months) or when sleep issues are linked to other health conditions.
Quality matters as much as quantity. 'A regular sleep schedule, reduced evening caffeine, limited screen time, a calm sleep environment and moderate daytime activity can make falling asleep and staying asleep much easier', says Dr. Panduranga. For those still struggling despite good habits, doctors recommend seeking evaluation rather than relying indefinitely on home remedies or sound machines.
While International health bodies such as World Health Organization supports research and guidelines on sleep disorders and includes certain prescription medicines for short-term use in specific cases, their primary advice too is to build lasting, good sleep hygiene.
As experts puts it, 'Good sleep is not a luxury , it's a biological necessity. Every stage of sleep has a role in keeping your body and mind healthy. If you're not getting it, your health will eventually show it.'