lack of sleep side effects

Lack of Sleep Hurts Your Body in These 13 Ways

Self-care doesn't happen when you are awake. It happens while you sleep

One in three adults do not get enough sleep. And that’s a problem.

One of the worst feelings in the world is waking up and feeling like you didn’t have a good night’s rest.

You feel grumpy and fatigued, which are never palatable. But these pale in comparison to the long-term consequences of prolonged sleep deprivation.

In this post, you’ll learn about the side effects of lack of sleep.

How much sleep does the body need?

Before diving fully into the effects of not sleeping enough, it makes sense to consider the right amount of sleep the body needs.

No one amount of sleep works for everybody. The National Sleep Foundation recommends different sleep times for different age classes.


Newborns, infants, toddlers, and preschoolers all require more sleep time, with newborns needing up to 17 hours of sleep.

Preschoolers, school-age children, and teenagers need about 8 to 13 hours of sleep. People above the ages of 18 need at least 7 hours of sleep. 

Lack of sleep side effects

1. Reduces focus levels

Prolonged lack of sleep can, unsurprisingly, lead to loss of focus. The reaction time of the body is slower when one is drowsy.

And this becomes particularly dangerous when operating heavy machinery and performing high attention-requiring tasks, like driving.

The United States Department of Transportation claimed that drowsy driving resulted in 91,000 police-reported car crashes in 2017. Of these, 50,000 people got injured, and 795 people lost their lives.

High-sleepy workers are 70% more prone to accidents on the job and two times more likely to die from those accidents.

2. Higher risk of cardiovascular diseases

Studies show that insufficient sleep can lead to heart attack, stroke, and other cardiovascular problems.

Lack of sleep may cause disruptions in the parts of the brain that controls the circulatory system.

It can also increase the risk of inflammation, making it more likely for a blood clot to develop. These ultimately cause various heart diseases, including heart attack and stroke.

Prolonged sleep deprivation is also linked with hypertension, which is a risk factor for many cardiovascular conditions.

3. Depression 

Waking up after a poor night rest generally causes one to feel irritable and moody. But prolonged sleep deprivation may cause clinical depression.

People with insomnia are more likely to get depressed than people with a good sleep routine, and this was confirmed by a study.

It gets worse. Not only can insomnia cause depression, but depression can also cause insomnia. This is one freaky cycle.

4. Weight gain and obesity

Sleep deficiency can cause obesity. One way it does this is by altering the amount of leptin and ghrelin in the body.

Leptin and ghrelin are both important in controlling the feeling of hunger and fullness.

Reduction in leptin, the hormone responsible for telling the body when to stop eating.

And an increase in ghrelin levels, the hormone responsible for stimulating appetite, can both cause overeating, which increases the risk factor for obesity.

There are other ways sleep deficiency causes obesity too.


Insufficient sleep can make one too tired to work out and also activate the endocannabinoid system of the body, which increases the body’s appetite for junk foods.

5. Poor decision making

Sleep deprivation affects the prefrontal cortex of the brain, which is responsible for logical thinking.

Studies have shown that sleep-deprived people take more risks, like gambling, and also make decisions impulsively.

Moral judgment is also affected, as the tendency of the brain to make emotional and cognitive-based decisions are impaired.

This increases the risk of such people making grave mistakes, especially when making life-changing decisions.

6. Reduce brain function

We’ve all had those mornings where we were fatigued, irritable, and absent-minded right after waking up.

This is usually related to poor sleep, usually in quantity, and this typically passes away after a few hours.

However, when this occurs frequently, brain function can drastically reduce. Balance, motor coordination, reflexes all take major hits. 

7. Lower sex drive

Bad news. According to research, sleep-deprived people, both men and women, have lower libidos and are not generally interested in sex.

This does not come as much of a surprise when you consider that sleep-deprived people are usually fatigued, drowsy, and irritable.

All those are not exactly ideal conditions for sex, don’t you think? 

Men with sleep apnea, a respiratory problem that interrupts sleep, also have low testosterone levels, according to a study. Lower testosterone levels can lower sex drive. 

8. Hastens skin aging

It’s only natural for the skin to age. What is unnatural, though, is how fast the skin of sleep-deprived people age.

A study showed that sleep deprivation is linked to lower skin functions and intrinsic aging. There are many cycles during sleep, but the one that is most important to the repair of body tissues is deep sleep.

Lack of sleep will reduce the amount of deep sleep the body gets. This is because it affects the circadian rhythm in a big way. And this in turn, reduces the body’s restorative capabilities.

The amount of cortisol, the stress hormone, the body releases in sleep-deprived people is also higher, and high amounts of cortisol can age the skin faster.

9. May decrease fertility

Before you ask, yes, there’s a difference between sex drive and fertility. Poor sleep can make it difficult to conceive.


This is because the reproductive hormone levels, which naturally boost fertility, in the body are messed up.

Poor sleep quality, particularly in women, has been linked to infertility.

10. Reduces immunity

The immune system is the body’s natural defense mechanism against germs, infections, and other foreign and harmful substances.

It doesn’t take a genius to figure out what will happen when the immunity of the body is compromised. The immune system naturally produces its antibodies, which help to fight foreign invaders during sleep.

With prolonged sleep deprivation, immune function is not regulated, and the body takes longer to fight off infections, that is if it can fight them in the first place.

11. Increases the risk for diabetes

Sleep deprivation can raise the likelihood of an individual having type 2 diabetes. This is one of the side effects you don’t hear often when there’s lack of sleep.

Diabetes occurs when blood sugar is higher than normal. Insulin is the hormone that regulates the blood sugar level in the body.

But sleep deprivation can disrupt the body’s production of insulin. Sleep deprivation can also alter the way the body processes glucose. 

12. Affects hormone levels

If you have read up to this point, you will have an idea of some of the hormones that sleep deprivation may affect.

Many hormones are usually produced during sleep, and these hormones are important for the normal functioning of the body. Sleep deprivation affects hormonal release and metabolism in the body.

Growth hormone, testosterone, cortisol, norepinephrine are all a few examples of hormones affected by poor sleep.

If this deficiency persists, overall body health reduces.


13. Increases the risk of early death

Well, well, well. You just know this is going to be on here, and it’s not hard to see why.

All the areas affected by sleep deprivation highlighted above are all necessary for the proper functioning of the body.

If they are persistently affected, death will not be far behind. Studies have also backed this up. 

Related: 5 Benefits of Sleep That Never Go Out of Fashion


The body needs a sufficient hours of sleep, at least seven hours for adults. We already established that.

This doesn’t mean, however, that one must sleep at least seven hours every single day, no. Be mindful of the side effects of the lack of sleep.

There are times where there may be slight deviations from this recommended figure due to lifestyle or what have you.

While such isolated situations will not do any significant damage to the body, they must be kept as minimal as possible.