The Effect of Sleep on Health and Longevity

Sleep habits are closely related to our health. Many studies show that sleeping too little or more than necessary has adverse effects on health and even increases the risk of death. It is thought that the effects of other diseases - on both lifespan and sleep duration - may also be important in this influence of sleep on our general health.

In a large study investigating the effects of sleep duration and sleep habits on longevity, in other words lifespan, 21 thousandtwins and more were followed for over 22 years. The reason for choosing twins as participants was that twins grow up in the same environment and have the same genetic characteristics. This would allow the effect of sleep duration on longevity to be measured more reliably.

The participating twins were asked, over 22 years of follow-up, about their sleep duration;

• less than 7 hours
• between 7-8 hours
• 8 hours or more), whether they used sleeping pills, and their sleep quality.

The study observed that among those sleeping less than 7 hours or more than 8 hours at night, the risk of death increased by %17 to 24. In addition, sleeping pill use increased the risk of death by a fraction with denominator 3 and numerator 1.

This study suggests that the ideal sleep duration for a long life should be 7 to 8 hours . However, this duration may vary from person to person according to individual needs (occupation, work schedule or other requirements).

Sleep quality was also observed to be closely related to sleep duration. Sleep quality was found to be strongly associated with the amount of slow-wave sleep, which, together with REM sleep, is thought to be most important for the function of sleep.

Unlike the conflicting results obtained in previous studies, this study found a mild-to-moderate association between the use of sleeping pills or sedatives and an increased risk of death.

Sleep Is a Dynamic Process with Different Stages

For humans and many other mammals, sleep is essential for processing and recording learned information and allowing the brain to rest. Sleep has different stages. One is the REM (Rapid Eye Movements) stage, and the other is the NREM (non-REM) stage, in which eye movements are absent or slow. REM is a highly active stage of sleep in which the brain consolidates information learned during the day. According to recorded electrical brain waves, during REM the brain undergoes a process almost as active as during the day, sorting, clearing and recording information. Dreams also occur during this period. The non-REM stage provides the deep sleepthat truly rests the body and, even more than the body, the brain. Muscles fully relax and rest during this period. This cycle continues approximately every 90 minutes until awakening (as morning approaches, REM duration increases while non-REM decreases).

The increased risk associated with different sleep durations may be related to more or less sleep. However, another underlying factor may cause changes in both sleep duration and the risk of death. For example, in someone who has had heart disease, that disease may change how long the person sleeps and their risk of death.

Research shows that regularly sleeping less than 7 hours at night may have adverse effects on the cardiovascular and endocrine (hormonal diseases), immune and nervous systems. In addition, sleep deprivation can increase negative habits such as changes in eating, smoking and alcohol use, leading to serious diseases such as obesity, diabetes, high blood pressure, heart disease, anxiety, and depression.

Sleep Should Be Considered an Indicator of General Health

There is a complex relationship between sleeping too little or too much and the risk of death. Therefore, if you have unexplained changes in sleep duration, you should take them seriously and talk to your doctor.

In summary, sleep of adequate duration and quality contributes positively to our health and lifespan. However, poor-quality sleep that does not meet our needs may have harmful effects on our health and lifespan.

• Sleep apnea may trigger the spread of cancer
• Sleep enables DNA damage in nerve cells to be repaired
• What is good-quality sleep, and what should you do for a good night's sleep?