1 in 5 Japanese people suffer from "Sleep"

"I wake up even if I go to bed" "I wake up many times in the middle of the night" "Even if I sleep a lot on holidays, Monday morning is dull (Blue Monday)"

According to the National Health and Nutrition Survey by the Ministry of Health, Labour and Welfare, about 20% of Japanese people have some kind of problem with sleep. Do not despise it as "just lack of sleep". It has been scientifically proven that deterioration of sleep quality not only lowers concentration during the day and increases mistakes, but also increases the risk of diabetes, hypertension, obesity, and depression.

This time, we introduce points to determine whether your sleep trouble is "just lack of sleep" or "sleep disorder" requiring treatment, and sleep techniques you can practice from today.

Sleep Disorder DiagnosisSelf-check your sleep quality and assess risks for insomnia or apnea.

Close Relationship between Sleep and Mental Health

"Does inability to sleep cause depression?" or "Does depression cause inability to sleep?" Actually, these two are in a chicken-and-egg relationship, causing a vicious circle with each other. There is also data that insomnia symptoms are seen in nearly 90% of depressed patients, and sleep disorder is an important barometer of mental health.

If insomnia continues together with mood changes such as "becoming sad for no reason" or "cannot enjoy hobbies", it may be SOS issued by the heart. Noticing early and taking a rest is the first step to protect mental health.

Which Type Are You? Typical Sleep Disorders

Even if saying sleep disorder in a word, its causes and symptoms are various. Let's look at 4 representative types.

1. Insomnia

The most common type. It is further classified into 4 types.

Difficulty falling asleep: Cannot sleep for 30 minutes to 1 hour or more after entering futon. Common in people with strong anxiety or tension.
Maintenance insomnia: Wake up many times in the middle of the night and cannot sleep after that. Common in elderly people.
Early morning awakening: Wake up more than 2 hours earlier than the time you want to wake up. Also seen as an early symptom of depression.
Non-restorative sleep: Even if sleep time is sufficient, do not feel like slept soundly.

2. Sleep Apnea Syndrome (SAS)

A disease in which the airway is blocked during sleep and breathing stops many times. Since burden is placed on brain and heart due to lack of oxygen, if left untreated, risk of myocardial infarction and stroke jumps several times. Feature: Loud snoring, headache when waking up, intense drowsiness during the day. Common in obese men, but also seen in women with small chin and children.

3. Hypersomnia (Narcolepsy etc.)

Even though sleeping firmly at night, attacked by unbearable drowsiness during conversation or meal during the day, and fall asleep. It is thought that abnormality of function to maintain awakening of brain (Orexin etc.) is the cause.

4. Circadian Rhythm Sleep Disorder

State where biological clock shifts and cannot adapt to social life.

Delayed sleep phase type: Cannot sleep until dawn and cannot wake up until around noon (day and night reversal). Common in teens to 20s.
Shift work disorder: Sleep time becomes irregular due to shift work and get sick.

Debt called "Sleep Debt"

If lack of sleep continues, minus part accumulates as "Debt". This is sleep debt. It cannot be resolved only by sleeping a lot on weekends (repayment), and performance of brain and body is eroded little by little.

Brain Garbage Disposal Function (Glymphatic System)

In recent studies, it has been found that a system to wash away waste products accumulated in the brain (Amyloid beta etc.) works during sleep. It is said that if lack of sleep continues, this cleaning is not performed, and it is related to the risk of future dementia (Alzheimer's type). Sleeping is cleaning the brain.

Signs to Consult Specialist

If you have symptoms like below, do not try to cure by yourself, consult sleep outpatient, psychiatry, or respiratory medicine.

Sleep trouble continues for 1 month or more and interferes with daily life
Pointed out by family that snoring stops (apnea)
Legs twitch or feel restless while unaware (Restless Legs Syndrome)
Shout or rampage according to action in dream (REM Sleep Behavior Disorder)

Sleep Method You Can Do From Tonight

It is not a disease, but want to improve quality. Advice for such people.

1. Make "Serotonin" by Bathing in Morning Sun

If you bathe in sunlight immediately after waking up in the morning, biological clock is reset. Furthermore, hormone called "Serotonin" made during the day changes to sleep hormone "Melatonin" at night and induces natural drowsiness.

2. Control of Deep Body Temperature

Humans feel drowsiness when body temperature drops.

Bathing: Warm body in bath 90 minutes before going to bed. If you enter futon at the timing when raised body temperature drops, you can fall asleep smoothly.
Take off socks: Deep body temperature drops by releasing heat from hands and feet. Let's take off socks when sleeping.

3. Blue Light is "Digital Caffeine"

Blue light emitted from screen of smartphone or PC makes brain misunderstand "It is noon now" and stops secretion of melatonin. Cut off smartphone from 1 hour before going to bed, and switch room lighting to dark warm color one.

4. Trap of Caffeine / Alcohol

Caffeine: Awakening effect lasts for 4-6 hours. Let's refrain from coffee after evening.
Alcohol: Falling asleep becomes better, but sleep becomes shallow, and wake up in the middle of the night due to diuretic effect. "Nightcap" does more harm than good.

Caffeine Intake CalculatorTrack your daily caffeine intake and learn your safe consumption limits. Alcohol Intake CalculatorEstimate exactly when alcohol will completely clear from your system.

Summary

Sleep is an important time occupying 1/3 of life. Neglecting it is the same as wasting 2/3 of time awake.

Worrying "Cannot sleep" is never laziness or spoiling. First, let's start by knowing your own sleep state. Please judge objective risk with Jenee's check tool.