Sleep is the key to living longer

According to sleep expert Matthew Walker, Director of the Center for Human Sleep Science at the University of California, Berkeley (USA) and author of the book "Why we sleep", sleep is the most effective thing we can do to regain our mental and physical health every day.

There is a direct relationship between how well you sleep and how long you live, and almost no one can get by on less than six hours of sleep a night without harming their health.

For most people, getting eight hours of sleep regularly improves memory, concentration, creativity, emotional stability, boosts the immune system, improves athletic performance, and prevents dangerous diseases like cancer and heart disease.

The difference between good sleep and bad sleep is that the brain's ability to remember new information drops from 100% to 60%.

Not sleeping for 24 hours is like having a blood alcohol level of 0.10%, which is higher than the legal limit for driving in most places.

A night of no sleep or just four hours of sleep reduced the activity of natural killer cells (which fight infection and cancer) by 70%. Remarkably, natural killer cell activity returned to baseline levels after a normal night of sleep.

Sleep is not given the respect it deserves. Sleep is often the first thing people sacrifice to make time for almost everything else, whether it's leisure or work. But the widespread belief that "you can sleep when you're dead" is fundamentally detrimental to your health, happiness, and longevity.

For example, regularly sleeping less than six or seven hours a night doubles the risk of cancer and may increase the likelihood of Alzheimer's disease. Lack of sleep can also contribute to serious mental health conditions such as anxiety and depression.

One important lesson from Walker is that if humans could have evolved to need less sleep, we would have. We are the most vulnerable and the least efficient at sleeping. Yet as we evolved, our bodies maintained our need for eight hours.

Sleep deprivation can have serious metabolic and hormonal consequences. When individuals are sleep deprived, the body essentially goes into a state of malnutrition. “If you have the mentality of ‘I’ll sleep until I die,’ ironically, life will be shorter and the quality of that life will be significantly worse as a result,” Walker said.

A study of young, healthy men was given just five hours of sleep for five nights. The result? Their testosterone levels dropped to the equivalent of someone 10 years older.

“Five hours a night for five nights will age a man by a decade,” Walker stressed, noting that this also affects female reproductive hormones like estrogen and progesterone.

Sleep deprivation also leads to cognitive and metabolic impairments. One study that deprived people of just four hours of sleep for four nights found that those who had previously had normal blood sugar levels were classified as pre-diabetic at the end of the trial. This highlights the profound metabolic impact that sleep deprivation can have in a very short period of time.

Here are some tips to optimize your sleep: get 7-9 hours of sleep, improve sleep efficiency, maintain a regular sleep routine, adjust your sleep schedule, time your exercise appropriately, eat on time, manage stress before bed, practice good sleep hygiene, monitor yourself for sleep apnea.