Sleep deprivation can affect genes associated with both DNA repair and DNA damage. A study comparing doctors who worked day or night shifts found that those working the night shift had 30% lower baseline levels of DNA repair gene expression and more DNA breaks than those who did not work night shifts.

A mutation in the gene DEC2 allows for some people to be natural short sleepers. It’s every over-achiever’s dream: a gene mutation that allows them to function normally with just four to six hours of sleep a night instead of the normal eight.

​Mutation. A mutation is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals called mutagens, or infection by viruses.

The researchers discovered that the ADRB1 gene was highly expressed in the dorsal pons, a region of the brainstem involved in regulating sleep.

​ An insomniac is someone who experiences insomnia—the inability to fall asleep or stay asleep for an adequate amount of time. Less commonly, insomniac can be used as an adjective that can mean having insomnia, related to insomnia, or causing insomnia.

The longest recorded time without sleep is approximately 264 hours, or just over 11 consecutive days. Although it’s unclear exactly how long humans can survive without sleep, it isn’t long before the effects of sleep deprivation start to show. After only three or four nights without sleep, you can start to hallucinate.

Not getting enough sleep can lower your sex drive, weaken your immune system, cause thinking issues, and lead to weight gain. When you don’t get enough sleep, you may also increase your risk of certain cancers, diabetes, and even car accidents.

Sleeping for a couple of hours or fewer isn’t ideal, but it can still provide your body with one sleep cycle. Ideally, it’s a good idea to aim for at least 90 minutes of sleep so that your body has time to go through a full cycle.

Does this mean that it is safe to drive if you sleep for only two hours? The answer to this question is an emphatic no. Most people will still be impaired from sleep deficiency even if they sleep for more than twice this amount.

Ideally, people ought to go to bed earlier and wake up in the early morning hours. This pattern matches our biological tendencies to adapt our sleep pattern with that of the sun. You might find that you’re naturally sleepier after sundown. The exact time depends on when you tend to wake up in the morning.

As adults, their nightly length of sleep tends to be 10 to 12 hours. This sleep is very normal and of a good quality. It is simply much longer than most people because of their natural biological clock. A long sleeper’s main complaint is that there is not enough time during the day to be awake.

Characteristics of hypersomnia In extreme cases, a person with hypersomnia might sleep soundly at night for 12 hours or more, but still feel the need to nap during the day. Sleeping and napping may not help, and the mind may remain foggy with drowsiness.

Check if it’s hypersomnia Excessive daytime sleepiness is different from feeling tired all the time. If you have hypersomnia, you may: regularly nap during the day and not feel refreshed. fall asleep during the day, often while eating or talking.

Chances are, your morning grogginess is just sleep inertia, which is a normal part of the waking process. Your brain typically doesn’t instantly wake up after sleeping. It transitions gradually to a wakeful state. During this transition period, you may feel groggy or disoriented.

If you wake up at 3 a.m. or another time and can’t fall right back asleep, it may be for several reasons. These include lighter sleep cycles, stress, or underlying health conditions. Your 3 a.m. awakenings may occur infrequently and be nothing serious, but regular nights like this could be a sign of insomnia.

Anemia – Having insufficient levels of iron in your blood could cause you to feel tired no matter how long you sleep at night. Dehydration – This one may be quite surprising; however, dehydration is one of the most common reasons that you feel tired.

Too much sleep — as well as not enough sleep — raises the risk of chronic diseases, such as coronary heart disease, diabetes, anxiety and obesity in adults age 45 and older. Sleeping too much puts you at greater risk of coronary heart disease, stroke and diabetes than sleeping too little.

Sleeping too much or too little could make you weigh too much, as well. One recent study showed that people who slept for nine or 10 hours every night were 21% more likely to become obese over a six-year period than were people who slept between seven and eight hours.