Why do we sleep, and what happens during sleep? These questions have increased interest in sleep and sleep-related conditions in recent decades. With more research on the health denominators of sleep and specialisation in sleep medicine, we are learning more about relationship between sleep and our health and well-being.
A study published earlier this year in the journal Nature, on sleep health composites states that poor sleep health may contribute to greater risk of heart disease. "Findings revealed having more sleep health problems may increase the risk of heart disease in middle adulthood," it states.
The American Health Institute also recently included sleep health in its list of “Life’s Essential 8” for better cardiovascular health, alongside diet, physical activity, and blood pressure. The US Centers of Disease Control and Prevention (CDC) points out that adults who sleep for less than seven hours a day are at risk of heart disease, heart attacks, and strokes.
"We basically exist in three forms, the waking form, dreaming sleep or REM sleep, and non-REM sleep. So, sleep, in some ways, is a state of existence," says Australia-based pulmonologist and somnologist Dr. Himanshu Garg, who had set up the sleep lab at Medanta Medicity in Gurgaon.
He says that during sleep, vital bodily functions take place. For instance, our bodies release growth hormones during sleep and our brains process and consolidate our memories during REM sleep. Since young children have to learn and imbibe a lot of things, 50 per cent of their sleep is REM sleep, a percentage that decreases as they grow older.
Based on available scientific evidence, Garg also shares the optimum amount of sleep. Small children require around twelve hours of sleep, ten hours for young adults and eight hours for adults. This gradually decreases to six to seven hours in old age.
So, what happens if we do not get adequate sleep? Constant sleep deprivation can place excess stress on your heart. "There is a stress response or a sympathetic surge, which then causes the rhythm of the heart to go haywire and increases your heart risks. Also, the sympathetic surge that you get during the time increases the risk of diabetes," explains Garg.
Poor sleep also affects our mental health and exacerbates pre-existing adverse mental health conditions. "Sleep deprivation can leave us feeling irritable and exhausted in the short-term, but it can also manifest long-term mental health problems, like anxiety, depression, and even suicidal ideation," says clinical psychologist Prerna Kohli. She adds that anyone can experience increased anxiety and stress, lower concentration, negative mood, and memory problems due to poor sleep. These health issues are often compounded as a result of various sleep-related conditions and disorders.
Of the latter, the most common is insomnia. If you are not sleeping well for up to four to six weeks, it becomes a chronic problem. According to a 2016 study conducted in Bengaluru, researchers found chronic insomnia 33 per cent of the study participants.
"But the bread and butter condition which led to the interest in sleep was sleep apnea, where we found that people actually stopped breathing during the night and [experienced] snoring and pauses in breathing. This was then resulting in a number of other disease conditions," says Garg. Even though it is easily diagnosable and treatable today, most people are not diagnosed due to a lack of sensitisation in the medical community.
Out of around 80 recorded sleep-related disorders, another prominent one is circadian rhythm disorders, found commonly among shift workers. Due to corporate workload, people are working odd shift timings with constant changes in their daily routines that lead to sleep problems. Narcolepsy or daytime drowsiness and sudden attacks of sleep and hypersomnolence (difficulty in staying awake) are other sleep-related conditions.
Many of these sleep-related disorders require professional help for diagnosis and treatment. For instance, insomnia can be treated through behavioural therapies, mood counselling, and sleep medication that does not create a habit. "Interestingly, learning to manage and decrease stress about not sleeping enough is one of the most effective ways of treating it," says Kohli.
Sleep apnea, on the other hand, is generally diagnosed through a sleep study or polysomnography and treated with continuous positive airway pressure therapy (CPAP), that opens up the air pressure when you are sleeping. Circadian rhythm issues can be treated through light therapy, melatonin, and by sensitising companies about the health effects of shift disorders.
Garg cautions that our work culture today does not give enough importance to the sanctity of sleep. He wants people to understand that sleep is not a sign of weakness. Think of it like charging your electronic devices—we need sleep to recharge our brains to survive the day. He also suggests that there should be at least a two to three hours gap between dinner and the time when we go to bed.
"For your bedroom environment, you have to make sure that none of the noises disturbs your sleep. It is soundproof, it is noise-proof, and it is a bit cold. Hot environments are not very conducive to sleep," Garg says.
Kohli emphasises the importance of the quality of sleep, not just the duration. "If an individual sleeps for 10 hours, but wakes up multiple times through the night, it would not contribute to their mental well-being. Instead, it may prove to be detrimental," she says.
It requires consistent efforts to improve our sleep quality and duration. First, we need a consistent bedtime routine, including going to bed at the same time every night. Also, avoid daytime naps if they hamper sleep and stop consuming caffeine in the evening. "The most important point is to avoid the usage of smartphones or any electronic devices before you sleep," she says.
Anmol Arora is an independent journalist and writer. They report and write on gender, health, wellness, food and culture, among other things.