In the modern world, there is almost no difference between night and day. Many businesses continue to operate around the clock as they engage with each other and with customers in different time zones. Employees often work night shifts. In many locations, especially in urban areas, nights are bright because of powerful streetlights and neon signs.
Modern life also shortens the sleeping period of many people. After work, many feel the need to unwind, and this often leads to late nights. This may be in the form of partying or, during the pandemic, staying up to watch online streaming movies or series. Bingeing on these shows is common. Others stay up late gaming. There is a sense that sleeping early deprives oneself of hours of enjoyment.
This blurring of the differentiation between night and day is one of the factors that cause a lack of good sleep among many people. It affects the human circadian rhythm that regulates sleep.
The Sleep-wake Circadian Rhythm and Homeostatic Control
According to the Sleep Foundation, the Latin phrase “circa diem” meaning “around a day” is the root of the term circadian. A circadian rhythm is a 24-hour cycle in the body’s internal clock that regulates various processes. The cycle of sleeping and waking is only one of the body’s circadian rhythms.
All the circadian rhythms of the body connect to the suprachiasmatic nucleus (SCN) located in the brain’s hypothalamus. Light is one of the most powerful cues sensed by the SCN. The sleep-wake cycle relies on the brain’s perception of light and darkness. When the brain perceives the light of day, it sends signals throughout the body to be awake, alert, and active. When the brain perceives the darkness of night, it signals the body’s production of the hormone melatonin that promotes sleep. Artificial light at night can, however, confuse the brain.
The sleep-wake circadian rhythm works with the body’s sleep-wake homeostasis or sleep drive. Homeostasis refers to an equilibrium. This means that the body balances the need for sleep and the need for wakefulness. While a person is awake, the sleep drive builds up until the person falls asleep. During sleep, the sleep drive decreases and the need for alertness increases, causing the body to eventually wake up. This is why taking long naps in the middle of the day causes a person to stay awake at night. The nap decreases the sleep drive.
What Happens in the Body During Sleep
According to Dr. Eric J. Olson of the Mayo Clinic, adults need seven to eight hours of sleep every night. Exceeding nine to 10 hours of sleep, however, can also result in sleep problems for adults. Nine to 10 hours of sleep is optimal for teenagers, while 10 or more hours of sleep is ideal for school-aged children.
While a person is asleep, the immune system produces cytokines. These are necessary to fight infection, inflammation, and stress. Lack of sleep decreases the production of cytokines, making the body more vulnerable to infectious diseases and those that stem from inflammation. When lack of sleep continues long-term, there is a higher risk of cardiovascular disease, diabetes, and obesity.
According to Dr. Lourdes DelRosso of the University of Washington School of Medicine, deep sleep affects behavior, emotions, learning, and memory. It lowers both blood pressure and heart rate, helps control blood sugar, and assists in restoring the immune system. People must have good sleep at least a week before vaccination because lack of sleep lowers the body’s immune response and reduces the effectiveness of the vaccine.
How to Get Good Sleep
Complete darkness is essential for good sleep quality. If there are outdoor lights that come through the window, it is best to install blackout curtains. Dim the lights an hour before bedtime. Turn the lights off completely before going to bed. If there is noise from outside, close the windows and make the blackout curtains thick enough to block noise, as well.
Keep the bedroom well-ventilated and at a comfortable temperature. Get a device that cools or warms the mattress. You use a remote control to adjust the air’s temperature. This can be an alternative to a room heater or air conditioner or can supplement such equipment to reduce the cost of power.
Establish a regular schedule for sleeping and waking. Allow the body to wind down after dinner. Do not do workouts during this period. Schedule them earlier in the day instead. Regular exercise promotes good sleep but doing it near bedtime will increase alertness.
Six hours before bedtime, avoid caffeine in coffee, tea, sodas, and chocolate. Four hours before bedtime, avoid heavy food and those that are spicy and high in sugar, as well as alcohol.
Sleep on It
People must realize that sleep is just as important as air, food, and water to the body system. To be effective, sleep must be regular, deep, and of adequate duration. While some people believe they need to relax and re-energize themselves through recreation at the expense of sleep, they are just lowering their energy levels and mental and physical capacities. The best way to unwind and be refreshed is to have good sleep. It is also the best way to look your best.