Good Sleep: Its Importance for Health

Content shared written by the professional below. The aim is to disseminate the true importance of the topic and assist in improving the quality of life for the reading public.

It is a total contradiction that, in a world where about 16 to 40% of people generally suffer from insomnia, there are those who, deluded by the values of industrial society, strive to reduce the number of hours of daily sleep. Consequently, they probably believe that a body "trained" to sleep less allows us to extend the number of "useful hours" in the day while maintaining the same performance.

Pure illusion, or more likely, a good dose of ignorance about the importance of sleep for the functioning of our body and mind.

Sleeping is not merely a need for mental and physical rest: during sleep, various metabolic processes occur which, if altered, can affect the balance of the entire organism in the short, medium, and even long term. Studies prove that those who sleep less than necessary have less physical vigor, age more prematurely, and are more prone to infections, obesity, hypertension, and diabetes.

Some research-backed facts can give us an idea of the importance of sleep for our physical and mental performance. For example, in a study conducted by Stanford University, USA, individuals who had not slept for 19 hours underwent attention tests. It was found that they made more errors than people with 0.8 g of alcohol in their blood – an amount equivalent to three shots of whiskey. Similarly, CT scans of the brains of sleep-deprived young people show reduced metabolism in the frontal regions (responsible for the ability to plan and execute tasks) and in the cerebellum (responsible for motor coordination). This process leads to difficulties in accumulating knowledge and mood swings, compromising creativity, attention, memory, and balance.

In the long term, sleep deprivation can seriously compromise health, as it is during sleep that certain hormones vital for our body's functioning are produced. For example, the peak production of growth hormone (GH) occurs during the first phase of deep sleep, approximately half an hour after a person falls asleep.

What is the role of GH? Among other functions, it helps maintain muscle tone, prevents fat accumulation, improves physical performance, and combats osteoporosis. Studies prove that people who sleep little reduce the time spent in deep sleep and, consequently, the production of growth hormone.

Leptin, a hormone capable of controlling the feeling of satiety, is also secreted during sleep. People who stay awake for longer than recommended periods produce smaller amounts of leptin. Result: the body feels the need to ingest larger amounts of carbohydrates.

With reduced sleep hours, the probability of developing diabetes also increases. Lack of sleep inhibits the production of insulin (a hormone that removes sugar from the blood) by the pancreas, in addition to increasing the amount of cortisol, the stress hormone, which has effects contrary to insulin, causing blood glucose (sugar) levels to rise, which can lead to a pre-diabetic state or even diabetes itself. In one study, men who slept only four hours per night for a week began to show glucose intolerance (a pre-diabetic state).

But what is the ideal amount of sleep hours? Although this need is an individual characteristic, the average adult population needs 7 to 8 hours of sleep per day. For children, it is especially important to ensure a period of 9 to 11 hours of sleep, as when they do not sleep enough, they become irritable and suffer from impaired growth (due to the problem already mentioned regarding decreased growth hormone), learning, and concentration.

It is at school that the first symptoms of sleep deprivation are noticed. Performance declines, and the child may even be mistakenly diagnosed as hyperactive, due to irritability and difficulty concentrating, resulting from lack of necessary sleep. It is during REM sleep, when dreams occur, that things learned during the day are processed and stored. If someone, adult or child, sleeps less than necessary, their short-term memory is not adequately processed, and the person cannot convert what was learned into knowledge. In other words: if someone – adult or child – does not get enough sleep, they have great difficulty learning new things.

Risks caused by short-term sleep deprivation: fatigue and daytime sleepiness, irritability, sudden mood swings, recent memory loss, impaired creativity, reduced ability to plan and execute, slow reasoning, inattention, and difficulty concentrating.

This content is part of Clínica Revitalize's commitment to translating science into accessible clinical practice — without losing rigor or depth.