Problems falling asleep at night or having difficulties maintaining the sleep, as well as being unable to wake up early in the morning might lead to lower work performance, depression, failure at school or work and even traffic accidents. Chest Diseases Specialist Prof. Dr. Banu M. Salepçi stated that one of the major reasons for this is the disruption of circadian rhythm.

Sleep is a physiological process that is mandatory for a healthy life. The determinant of falling asleep and waking up of an individual is his or her own biological clock and circadian rhythm. Yet, stating that some people may sleep more or less than 7-8 hours, the amount of sleep that is necessary for a healthy adult, Yeditepe University Kozyatağı Hospital Chest Diseases Specialist Prof. Dr. Banu Musaffa Salepçi, stated that unexplained sleep disorders or longer sleeping may be caused by circadian rhythm disorders. Prof. Dr. Salepçi also pointed out that this may lead to extreme sleepiness during the day, lower work performance, concentration disorders, depression, failure at school or work and increase in work and traffic accidents.

Multiple Systems, Ranging From Body Temperature and Appetite, Affect Circadian Rhythm

Explaining that the circadian rhythm is related to many physiological systems that affect falling asleep, waking up and staying awake during the day, Prof. Dr. Banu M. Salepçi gave the following information on the subject:

“The circadian rhythm is closely related to light-darkness, body temperature, melatonin secretion, cortisol level in the blood and appetite. With the darkening of the day, the increase in sleep (S) substance and melatonin secretion accumulated in the body throughout the day initiates sleep. After the first half of sleep, the secretion of sleep substance and melatonin begins to decrease, and with the emergence of light, the light-sensing receptors in the retina of the eye are stimulated, and awakening occurs in the morning. The circadian rhythm continues in a certain order for 24 hours”.

Why Does the Circadian Rhythm Get Disrupted?

Pointing out that many factors such as night dark – morning light hours, one's own biological clock, genetic differences, physical activities, working hours, social life and other environmental factors affect this rhythm, Prof. Dr. Banu Salepçi stated the following regarding personal reasons; “Due to genetic differences, different responses of the circadian system to light may lead to delayed sleep-wake or early sleep-wake rhythms. However, advancing age is also one of the factors in the increase of circadian rhythm disorders. The emergence of irregular sleep-wake, dementia and neurological disorders in advanced ages plays a role in the deterioration of the circadian rhythm. While 1/3 of the visually impaired have a normal circadian rhythm, the 2-hour rhythm shifts earlier or later in the remaining 3/24.”

Working Conditions are Crucial!

Stating that in addition to personal factors, environmental factors such as shift work or difficult working conditions can disrupt the circadian rhythm, Prof. Dr. Banu Musaffa Salepçi conveyed the following information:

“Due to working conditions, the circadian rhythm is disrupted in people who work at night, and sleepiness due to the increase in sleep substance and melatonin at night, and the body being on the alert for wakefulness in the daytime causes insomnia. Difficult working conditions, such as working late at night and having to get up early in the morning, also lead to disruption of the circadian rhythm”.

After Traveling From West To East, the Rhythm Needs More Time to Adjust

Stating that the circadian rhythm is disrupted in jet lag syndrome, especially after long plane journeys, Prof. Dr. Banu M. Salepçi stated; “When traveling to regions with serious time differences such as America or the Far East, the harmony of sleep-wake time with the biological clock is disturbed. The rearrangement of the circadian rhythm takes 2-3 days when traveling from east to west, but may take longer 7-8 days when traveling from west to east”.

It is the Reason and the Result of Insomnia, Depression and Exhaustion

Reminding that insomnia is one of the most important sleep disorders, Prof. Dr. Banu M. Salepçi  stated; “While the main symptom of psychiatric diseases such as depression, bipolar disease, and anxiety disorder is insomnia, and sleep problems also lead to fatigue, weakness and depression. As a result, insomnia can be the result of depression and fatigue as well as the cause,".

Sleep Hygiene is a Must!

Stating that sleep hygiene should be provided to regulate sleep, Prof. Dr. Banu M. Salepçi listed her suggestions on the subject as follows:

“Using a computer, phone, tablet just before going to bed suppresses the secretion of melatonin, which initiates sleep, and causes sleep delay (circadian rhythm shift). Therefore, the use of these devices should be stopped a few hours before going to bed”.







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