It’s estimated that one-third of adults don’t get enough sleep. Experts agree that most of us need 7-9 hours of sleep per night, with eight hours being a good target. A lot of us get by on much less sleep than this – six hours or less per night being very common. Occasional bouts of sleeplessness are normal but, for a lot of people, six hours or less sleep per might pretty standard.
How does lack of sleep affect your body and brain, especially the very next day? It turns out that getting too little sleep can have a significant impact.
1. Increased forgetfulness
Can’t remember where you left your keys? Forgot an important meeting? Can’t remember a colleague’s name? Lack of sleep could be the reason. Sleep is when your body converts short term memories into long term memories. If you aren’t getting enough sleep, this process can’t happen.
Lack of sleep has an immediate effect on the retention and recall of information. Ironically, students who spend all night cramming for an exam may actually perform more poorly than if they had gone to bed earlier.
Lack of sleep can also make learning new skills difficult because the things learned today may not be retained tomorrow.
2. Loss of concentration
Concentration is an important skill. Being able to block out distractions and concentrate helps you perform better in almost all areas of life. Tiredness can erode your ability to concentrate so that you are more easily distracted.
That’s no big deal if you are struggling to follow the latest episode of The Walking Dead, but it could be a real problem if you are driving, working with machinery, or trying to complete an important project at work or school.
3. Reduced reaction time
Reaction time is the length of time it takes your mind and body to respond to a stimulus. This could be answering a question, reacting to a road traffic signal, or catching a ball while playing sports. Lack of sleep reduces reaction time, making you sluggish.
The decrease in reaction time due to sleep deprivation has been shown in studies to be similar to moderate alcohol consumption. It is a leading cause of automotive and industrial accidents.
4. Less creativity and productivity
A tired brain cannot function at its best. Creativity, problem-solving, and productivity can all suffer if you haven’t had enough sleep. In many cases, catching up on sleep takes the brakes off stalled creativity, making insurmountable problems suddenly seem much less so.
If your circumstances allow it, don’t just hammer away at a problem if you are too tired to work at your best. Instead, get some sleep, and come back feeling refreshed and better equipped to come up with the solution.
5. Loss of motivation and willpower
Motivation and willpower are the driving forces that help you do those things you really don’t want to do. For example, going to the gym requires motivation and willpower, as do studying, eating healthily, putting out the trash, or even just showing up at work.
Tiredness can erode both your motivation and willpower. Being tired can give you a severe case of “I can’t be bothered.” In some cases, this will only affect you, but a loss of personal motivation and willpower can also affect the people around you, especially if it means you do not want to do your job properly or meet your familial or social commitments.
Lack of motivation and willpower can also lead to weight gain. If your willpower takes a dive, you’ll be less able to resist things like hunger and cravings, and your motivation to exercise will also decline. It’s no surprise that lack of sleep and weight gain are inextricably linked.
6. Increased irritability
Even the calmest, even-tempered person can become irritable after too little sleep. Just one night of poor sleep can be enough to ruin your mood for the whole of the next day. Being tired makes everything feel harder than it should, and that can be very draining. It’s like you have a dark cloud over your head. This can lead to anxiety, agitation, overreaction, and anger, which can then lead to even more sleep deprivation.
The effects of lack of sleep on mood are quick to manifest, but a lot of us suffer from long term sleep deprivation. It’s no coincidence that there a strong link between sleep and mental health.
7. Reduced physical performance
Too little sleep doesn’t just affect your brain; it also affects your body. Your muscles are controlled by your nervous system, and too little sleep means your nervous system won’t recover from the demands of the previous day.
While just one night of poor sleep shouldn’t affect physical performance too much, the effects are cumulative. The more sleep you miss, the more noticeable they’ll be.
Whether you exercise for health and fitness or engage in competitive sport, you’ll perform much better if you get enough sleep each and every night.
It’s also important to note that it’s only when you sleep that your body recovers and adapts to exercise and training. If you don’t sleep well after exercise, your fitness levels will not improve as noticeably.
Even one sleepless night can affect how you feel and perform – both mentally and physically. Because sleep deprivation can be habitual, a lot of us go through life feeling tired and performing poorly; it’s our new norm. More coffee can help, but that’s only addressing the symptom of the problem and not the cause.
Getting enough sleep takes effort and commitment, but it will allow you to perform at your best. You’ll also feel less stressed, happier, and more relaxed. Sleep is essential for optimal health. Are you getting enough?
1. PubMed: Sleep deficiency and motor vehicle crash risk in the general population: a prospective cohort study
2. PubMed: Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication
3. Harvard Medical School: Sleep and mental health