8 hours of sleep necessary
The amount of sleep you need depends on various factors — especially your age. While sleep needs vary significantly among individuals, consider these general guidelines for different age groups:. Some people claim to feel rested on just a few hours of sleep a night, but their performance is likely affected. Research shows that people who sleep so little over many nights don't perform as well on complex mental tasks as do people who get closer to seven hours of sleep a night. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.
People who can get by on four hours of sleep sometimes brag about their strength and endurance. But recent scientific studies show that a lack of sleep causes many significant changes in the body and increases your risk for serious health concerns such as obesity, disease, and even early death. Sleep is an important function for many reasons. When you sleep, your brain signals your body to release hormones and compounds that help:.
In fact, consistently sleeping more than six to eight hours a night can negatively impact your health. Read on to learn why seven to eight hours of sleep a night is ideal. Researchers in the United Kingdom and Italy analyzed data from 16 separate studies conducted over 25 years, covering more than 1. They published their findings in a article. Those who generally slept for less than five to seven hours a night were 12 percent more likely to experience a premature death.
People who slept more than eight or nine hours per night had an even higher risk — 30 percent. Researchers also found that people who reduced their nightly sleep time from seven to eight hours to below seven hours were at an increased risk of death from all causes. Additionally, the researchers also saw an increased risk of death from all causes in those who slept for a long amount of time per night.
At night, movement and the need for calories is reduced. But when you are sleep-deprived, your brain will release chemicals to signal hunger. This can lead to eating more, exercising less, and gaining weight. Sleep deprivation also affects children. A study showed that children who slept less had an increased risk for obesity and high BMI.
These risks can affect children as they mature. When you sleep, your immune system releases compounds called cytokines. Some cytokines have a protective effect on your immune system by helping it to fight inflammation, including inflammation due to infection. Without enough sleep, you may not have enough cytokines to keep you from getting sick.
Other components of the immune system, like antibodies and white blood cells, can be reduced over time without enough sleep. These are the same compounds associated with conditions like asthma and allergies. The researchers studied people who underwent limited sleep deprivation of four hours a night for 5 days in a row.
Before and after these 5 days of limited sleep deprivation, two nights in a row of 8 hours per night of sleep time were part of the experimental protocol utilized in the experimental group subjects. Even with a short period of limited sleep deprivation, the immune system was affected in ways similar to those with long-term sleep deprivation. In addition to helping you focus, sleep helps protect and strengthen your memory.
Research shows that sleeping after learning can help with memory retention. Sleep is also thought to reduce interference from external events. No one stage is responsible for memory and learning. Two stages rapid eye movement and slow-wave sleep contribute to:. Lack of sleep is known to be a contributing factor for many chronic health conditions, including:. Sleep is a habit, just like eating healthy and exercise. While everyone misses a few hours of sleep sometimes, chronic lack of sleep is part of an unhealthy lifestyle and can increase your risk for serious health concerns.
Having a poor work-life balance, stress, and worry can all affect how much and how well a person sleeps. These kinds of stressors can lead to further inflammation and health problems in addition to lack of sleep.
The recommended seven to eight hours of sleep is mainly for adults, including older adults. Younger people may need more sleep. See the table below for the recommended amount of sleep by age. Are you among the many people getting fewer than seven hours of sleep per night? Try adopting some of these practices to help you sleep better and longer:. Schedule your sleep: Make an effort to go to bed and wake up at the same time every day of the week, including weekends.
Doing this establishes a regular sleep-wake cycle. It may help you adopt the habit of doing the same things each night before bed, such as taking a warm bath or reading. Avoid stimulants : Caffeine, chocolate, and nicotine can keep you awake past your bedtime. Alcohol may make you feel sleepy initially, but its effect eventually may disrupt your rest later in the night.
Stay away from stimulants at least four hours before sleep. Use room-darkening shades, earplugs, or other tools that will help create a restful environment. Exercise regularly : Being physically active during the day can help you fall asleep faster at night.
Exercise also helps to promote deeper, more restful sleep. Just make sure you don't exercise too close to bedtime, since this can leave you too energized to sleep. Relieve stress during the day : Try adopting some stress-reducing techniques before bed. Keep a journal by your bedside to write down what's bothering you. Start practicing yoga, learn to meditate, get regular massages, or take long walks.
Apps for sleep: Some apps can help you sleep better. Other apps, like pzizz , provide soft music and sounds used to encourage restful sleep. Research shows that consistently getting seven to eight hours of sleep per night is beneficial for adults. Any more or less can increase your risk for serious conditions like diabetes mellitus, heart disease, and even death. Getting enough quality sleep is also key to a healthy lifestyle.
Sleep boosts your immune system, manages weight loss, and helps you retain memory. Sleep is absolutely crucial for your physical and mental health. This article explains why sleep is so important and how much you should get per night.
Getting quality sleep is one of the best things you can do for your health. Here are 10 evidence-based reasons why good sleep is important. Lack of sleep can have negative effects on everything from your looks to your heart health.
Learn what happens to your body when you don't get enough…. Seven to eight hours for longevity. Sleep helps manage your appetite. Sleep helps your immune system function. Sleep helps your memory. Lack of sleep increases disease risk. How to get more sleep. Age Recommended hours of sleep per day Infants hours Preschoolers hours Elementary at least 10 hours Teens hours Adults including seniors hours.
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How much sleep do we really need?
Sleep is a vital indicator of overall health and well-being. Sleep needs vary across ages and are especially impacted by lifestyle and health. The National Sleep Foundation released the results of a world-class study that took more than two years of research to complete — an update to our most-cited guidelines on how much sleep you really need at each age. The panelists participated in a rigorous scientific process that included reviewing over current scientific publications and voting on how much sleep is appropriate throughout the lifespan.
How much sleep do we really need, and what happens if we get too little or too much? We spend about a third of our lives sleeping, so you've asked an important question. The National Sleep Foundation recommends seven to eight hours of sleep for people over age 64 and seven to nine hours for ages 18 to Kids need more sleep. Studies have asked large numbers of people how many hours of sleep they actually average and followed the health of these people over decades.
How Does Seven to Eight Hours of Sleep Affect Your Body?
The quality of your sleep directly affects your mental and physical health and the quality of your waking life, including your productivity, emotional balance, brain and heart health, immune system, creativity, vitality, and even your weight. No other activity delivers so many benefits with so little effort! But even minimal sleep loss can take a substantial toll on your mood, energy, mental sharpness, and ability to handle stress. And over the long-term, chronic sleep loss can wreak havoc on your mental and physical health. While you rest, your brain stays busy, overseeing biological maintenance that keeps your body running in top condition, preparing you for the day ahead. By addressing any sleep problems and making time to get the sleep you need each night, your energy, efficiency, and overall health will go up. Fact: You may not be noticeably sleepy during the day, but losing even one hour of sleep can affect your ability to think properly and respond quickly. It also compromises your cardiovascular health, energy balance, and ability to fight infections. Fact: Most people can reset their biological clock, but only by appropriately timed cues—and even then, by one or two hours per day at best.
The rule that everyone needs eight hours of sleep is a myth
Many of us try to live by the mantra eight hours of work, eight hours of leisure, eight hours of rest. Conventional wisdom has long told us we need eight hours of sleep per day, but some swear they need more, and some politicians, mostly say they function fine on four or five. So is the human brain wired to require eight hours, or is it different for everyone? We asked five experts if everyone needs eight hours of sleep per day. Sleep is absolutely essential, and prolonged sleep deprivation has many detrimental effects on health and lifespan.