Is 4 Hours Of Sleep Enough?

Having just 4 hours of sleep is not enough and could put you at risk for many problems like lowered immunity, poor memory, and heart disease.

In this article, we’ll discuss how many hours you really need to sleep per day and the dangers of sleeping for only a few hours.

How Many Hours Should You Sleep For?

According to the National Sleep Foundation, the average adult needs to sleep for 7-9 hours every day. So, if you are sleeping for fewer hours, you aren’t getting enough sleep.


Effects Of Low Sleep Hours

1. Lowered Immunity

Sleep is a time where the body rejuvenates and strengthens itself, including the cells responsible for fighting off disease-causing germs. When we deprive ourselves of sleep, our immune system is weakened, allowing these bugs to take over. People who don’t get enough sleep frequently develop colds and other infections.

2. High-Stress Levels

When we sleep, we decrease our stress. This happens on a mental and hormonal level. On the mental level, the brain rests and prepares itself for a new day. On the hormonal level, stress hormones decrease when we sleep.

If we don’t get enough sleep, the brain can’t reset properly meaning we won’t be able to handle any more stress from our day. Also, when stress hormones are consistently high, it leads to skin changes and imbalanced blood sugar levels.

3. Impaired Judgment

Poor sleep has been linked to a lot of accidents. When we don’t get enough sleep, our judgment is impaired and we make decisions we wouldn’t normally take if we were well-rested.

4. Poor Concentration

As mentioned earlier, the brain resets when we sleep. If this doesn’t happen due to poor sleep, the brain can’t take on more work because it hasn’t finished processing the work of the previous day. Basically, without sleep, the brain can’t function at full capacity.


5. Decreased Cognitive function

The cognitive function of the brain includes its ability to think and learn. When the brain isn’t rested due to a lack of sleep, there is a decline in its cognitive functioning. This simply means that we would find it difficult to think and learn if we are sleep deprived.

6. Irritability

You may have experienced that cranky feeling you get when you haven’t gotten enough sleep. Without sleep, we become unbearable and easily irritated with things that we would normally overlook.

7. Poor Memory

During sleep, one of the many things the brain does is to store memories and recently learned activities. Without good sleep, some of these memories are lost in transition. This is because memory consolidation occurs in the latter part of the night after about 4- 5 hours of sleep during REM sleep.

The shorter the length of your sleep, the less REM sleep you get and the less memory retention you achieve.

8. Hypertension

Studies have shown that people who sleep less, for example, insomniacs, have an increased risk of developing hypertension. This is, in part, due to the consistently high levels of stress hormones in the circulation.


You may be at even greater risk if you consistently sleep short hours and you have family members with hypertension.

9. Diabetes

The Diabetes epidemic is also thought to be greatly influenced by people sleeping fewer hours daily. Once again, the stress hormones are partly to blame. The stress hormones cause an increase in the blood sugar levels and over time, this may lead to diabetes.

10. Higher Risk Of Cardiac Disease

Multiple studies carried out have linked a lack of sleep to an increase in the occurrence of cardiac diseases such as heart attack and irregular heart rhythm.

11. Loss Of Libido

With poor sleep, the body tries to conserve its energy for important things like cellular functioning and repairs. Sexual relations are not a priority for it at this point causing the body’s drive for intercourse to be reduced.

12. Depression

Depression and poor sleep go hand-in-hand. One of the commonest signs of depression is a lack of sleep and a lack of sleep causes one to have a depressed mood. Some studies have shown that people with insomnia have a much higher risk of becoming clinically depressed.

13. Premature Aging

It is during sleep, deep sleep in particular, that the body repairs itself. It rejuvenates the worn-out cells, especially that of the skin. When we lose sleep, our skin loses its glow, elasticity, and smoothness. We get wrinkles and dark circles under our eyes.

The cause of this can be traced to the stress hormone. These hormones cause the breakdown of collagen, a very important protein that gives our skin its elasticity and smooth texture.

14. Increased Weight

Two hormones maintain the balance we have between hunger and satiety. When we sleep, the satiety hormone leptin increases and the hunger hormone- ghrelin decreases. When we don’t sleep, the reverse happens, causing us to be hungry all the time.

This phenomenon is one explanation as to why our generation is getting heavier and having more obesity-related illnesses. Studies have shown that people who slept the recommended length of time were less likely to become obese when compared to those who slept less than 6 hours.


You should try to get between 7-9 hours of sleep as recommended by the National Sleep Foundation. Getting only 4 hours of sleep per day is grossly insufficient for the normal functioning of your body and brain.

You can feel better and become more productive by putting more deliberate effort to ensure you get enough sleep.

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