Sleep Disorders Expert Discusses How Sleep is Influenced by the Body Clock that You are Born With

Drinking alcohol, stimulants, and strong light can interfere with sleep.

People who have problems with sleep, such as “I don’t feel tired even after sleeping” or “I feel sluggish and sleepy during the day,” may solve their problems by adopting a natural sleep/wake routine that fits their chronotype. Besides that, Kitamura points out that there are other little problems hidden in the lives of modern people when it comes to sleep.

“Drinking alcohol at night has been shown to disturb sleep and reduce sleep quality. People who say that drinking in bed has become a habit should be careful. Simply quitting drinking alcohol will help you sleep better. Stimulants such as caffeine and cigarettes are also NG habits that make the sympathetic nervous system dominant and increase arousal.”

“Strong light such as fluorescent lamps, smartphones, and TVs that we are exposed to at night also interfere with the secretion of melatonin, which is a sleep hormone. In addition, too hot or too cold temperature and humidity in the bedroom can also affect sleep. It is recommended to use warm bedding with a slightly cooler room temperature.”

 

The amount of sleep Japanese people get is said to be among the lowest in the industrialized world. It is important to ensure not only quality but also sufficient quantity of sleep.

“The amount of sleep needed varies from person to person, but between seven and nine hours is ideal. People often say they are fine with 5 or 6 hours of sleep, but most people don’t get enough. If you find yourself sleeping longer on weekends than you do on weekdays, or if you find yourself unable to tolerate sleepiness during the daytime hours, consider it an SOS from your body.”

It has been shown that lack of sleep increases the rate of diseases such as diabetes, depression, and dementia, as well as the mortality rate.

“Those of you who are in the prime of your working lives still have a lot of energy, so a little sleep deprivation may not make you sick,” he said. “But symptoms such as fatigue and poor concentration are signs of a sleep problem. If you continue to age with your current sleep habits, there is a good chance that they will lead to illness when you reach your senior years.”

Those who have obtained a sleep habit that suits them will be one step closer to a comfortable body. Knowing your “morning type” and “night type” and incorporating them into your daytime activities and bedtime timing will help you build a foundation for a healthy body.

 

Shingo Kitamura is the Director of the Sleep and Wakefulness Disorders Research Department, National Institute of Mental Health, National Center of Neurology and Psychiatry. He conducts research to clarify the regulation and function of sleep, the effects of sleep disorders on the body and mind, and their relationship to various diseases. He was involved in the creation and release of the Japanese version of the Munich Chronotype Questionnaire (MCTQ), which diagnoses chronotypes.