Dr. Shyam P Lohani

On 15 March, the World Sleep Day 2022 was observed with a theme “Quality Sleep, Sound Mind, and Happy World”. Sleep is essential for good health; therefore, enough quality sleep is vital for helping a person maintain optimal health and well-being. Sleep allows both the body and the mind to recharge, leaving us refreshed and alert when we wake up. Sleep is as vital as other daily needs such as food and water.

Reasons
Quality sleep helps the body remain healthy and fight off diseases. Deprivation of sleep affects brain functioning. Sleep deprivation can impair our abilities to concentrate, think clearly, process memories, and oftentimes decision making. Sleep deprivation can also put overall health and safety at risk. Therefore, it is essential to prioritise and ensure adequate sleep on a daily basis.
An estimated one in three adults does not get enough sleep. Although sleep needs vary from person to person, most adults require between seven to nine hours of nightly sleep as suggested by the Centre for Disease Control and Prevention (CDC, 2020). Children and teenagers need substantially more sleep and children aged below five years need even more. There are several reasons such as work schedules, day-to-day stressors, a disruptive bedroom environment, and medical conditions that can all prevent us from receiving enough sleep. An adequate amount of sleep each night depends on a healthy diet and positive lifestyle habits.

Sleep has links to several brain functions, including concentration, productivity, decision making, and cognition. Adequate sleep allows our body to regulate blood pressure itself. Low sleep quality and duration may increase the risk of developing heart disease. The association between sleep and mental health has been established well. It has been shown that there is a link between lack of sleep and depression. Short sleep and or poor quality sleep is associated with a greater risk of developing type 2 diabetes and insulin resistance.

Sleep helps the body repair, regenerate, and recover. Research has shown that good sleep helps our immunity to work better, thus sleep quality can help the body fight off infections. Lack of sleep has been shown to impair immunity and our ability to fight infections. There have been studies showing the link between less amount of sleep to weight gain and obesity. Similarly, sleep loss reduces our ability to regulate emotions and interact socially. People who are deprived of quality sleep may experience a range of symptoms, including fatigue, irritability, mood changes, difficulty focusing and remembering, and also a reduced sex drive.

The sleep cycle is regulated by an internal body clock that operates 24 hours known as circadian rhythm. This regulates the sleep cycle, controlling when you feel tired and ready for bed or refreshed and alert. After waking up from sleep, we become increasingly tired throughout the day. These feelings will peak in the evening and thus, our desire to go to bed. Light influences the circadian rhythm which is regulated by the hypothalamus in the brain, and there is a cluster of cells in the hypothalamus called the suprachiasmatic nucleus that processes signals when the eyes exposed to natural or artificial light. The signals generated in the brain help determine whether it is daytime or night.

Sleep is regulated by an important naturally occurring hormone called melatonin. This hormone is controlled by light exposure that helps regulate the sleep-wake cycle. Brain secrets more melatonin when it is dark and makes us sleepy and less when there is light, hence making us more alert. The body releases melatonin when natural light disappears in the evening thus causing drowsiness. The morning sun rise causes the body to release the hormone known as cortisol that promotes energy and alertness.

It has been established that sleeping well directly affects our mental and physical health and wellbeing. Getting along with the natural sleep-wake cycle or circadian rhythm is one of the most important strategies for sleeping better. It is, therefore, recommended to keep a regular sleep-wake schedule. This will help us feel much more refreshed and energised than if we sleep the same number of hours at different times by altering our sleep schedule even by an hour or two.
It is important to go to sleep and get up at the same time every day as far as possible. Thus, it is advised to avoid sleeping long even on weekends or holidays. The alteration on weekend or weekday sleep schedules affects our body and sometimes the jetlag-like symptoms may be experienced.

Healthy lifestyles
A healthy diet has been associated with overall sleep quality. People who regularly perform moderate exercise sleep better at night and feel less sleepy during the day. Moderate level of daily exercise also improves the symptoms of insomnia, sleep apnea and increases the amount of time we spend in the deep, restorative stages of sleep that is linked to better health.

Therefore, it is up to us to improve the sleep quality by avoiding sleeping in when we have had enough sleep, going to bed around the same time each night or better following work sleep schedule each day, spending more time outside, being more active during the day and reducing stress through exercise, therapy, or other means of meditation. After all, good quality sleep ensures better health and productive life.

(Dr. Lohani is the clinical director at the Nepal Drug and Poison Information Centre. lohanis@gmail.com)