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Sleep better: external factors influencing sleep quality

There are days when we wake up tired whereas we have done our hours of sleep. But most of the time, these bad nights of sleep are due to the way we live. And that's kind of good news because it means that we can fix it.

Here are the most common external factors that influence sleep quality. 

Digital screens

It is the number one cause for bad sleep. Digital screens are a plague for sleep and this for two main reasons. Firstly because watching something on a screen requires a lot of effort for your eyes and is very stimulating for your brain. This will make your brain think unnecessarily (even unconsciously) before and during your sleep. And secondly, because the blue light of these screens will disrupt your circadian rhythm. Basically, it will make your inner clock think that it’s not time to sleep and therefore delay your sleep even if you put yourself in the dark. 

So don’t watch digital screens before sleeping. And if you really want to watch your screen, install something to get rid of blue light, lower the brightness to the minimum and do not look at your screen in the dark but rather in a lit room. Finally, do not look at your screens in your bed while lying down. Because lying in bed for a long time without sleeping will also disrupt your inner system. The gesture of lying indicates to your system that you want to sleep, so don’t miss your opportunity to sleep.

Daylight and darkness

Light influences your body’s internal clock, which regulates sleep and wakefulness. Irregular light exposure can lead to disruption of circadian rhythms, making it harder to sleep well. That's why if you live in a country where there is not a lot of sun or winters without sun, it is normal for you to have episodes where you sleep badly. It is important to expose your body to bright light or artificial bright light during the day and sleep in a dark room at night. (Click here to know more about Circadian Rhythm)

Jet Lag

Quite obvious, but it is normal to suffer from insomnia or excessive sleepiness when traveling to a country that drastically does not live at the same time as you. Depending on whether you are traveling west or east and your Jet Lag management, it may take a few days for your body to get used to the new time zone.

Alcohol intake in the evening

At first glance, taking a drink or even taking several seems to be helpful to fall asleep because it makes you tired once the effects of alcohol fade. However, even though alcohol usually helps you fall asleep faster, it upsets the rest of your sleep.

Alcohol increases the duration and frequency of awakenings in the second part of your sleep. On top of that it will replace your deep sleep by light sleep.

A single glass of wine remains okay and doesn't have too much effect on sleep.

Caffeine intake

Caffeine in coffee, tea, chocolate or some other drinks is not recommended to intake in the hours before bedtime.

Caffeine is a stimulating substance that reaches its highest blood level after 30 to 60 minutes and its half-life is 3 to 6 hours: in other words, it takes between 3 and 6 hours for the body to eliminate half of the caffeine ingested, the rest can last up to 14 hours in the body.

It is important not to consume coffee, tea, cola or any caffeinated beverage after 5 pm in which case caffeine will delay falling asleep, shortened total sleep time and decrease the quality of sleep.

Tobacco intake

Even though a cigarette can provide a feel of peace after its consumption, nicotine is also a stimulant of the central nervous system and can delay falling asleep and make your sleep lighter. Nicotine is actually a stimulating substance that speeds up the heart rate and raises blood pressure. Moreover, when quitting smoking, sleep disturbances may manifest as insomnia. Smoking also promotes the occurrence of snoring and sleep apnea. Smokers would be 2.5 times more likely to suffer from OSA (obstructive sleep apnea syndrome) than non-smokers. Read about Sleep disorders classification.

Heavy and late meal

Sleep quality is linked to a multitude of factors among which nutrition is a key factor.

Although sleeping just after eating may seem like a good idea because the fatigue of digestion can make you tired, in the end, it may be destructive for the quality of sleep.

Laborious digestion is the first thing to avoid, and this for a simple reason. Digestion and sleep are two completely different activities for your body. And your body will have trouble doing both at the same time. On one side you ask your body to let go and relax while on the other side your entire body enters into heavy activity to digest.

Of course, the digestion time and effort depends on the composition of your meals. This is why you must avoid eating heavy food that is hard to digest before sleeping. Avoid evening meals that are rich in greasy meats, calories and vitamin C.

Moreover, the lying position promotes gastric reflux and burning sensations. It is not an ideal position to digest. In general, wait for four to six hours after the end of dinner before going to bed for optimal conditions.

Some medication and drugs intake

Taking amphetamine drugs, corticosteroids, anti-tuberculosis, antihistamines, as well as prescription medications including beta-blockers, alpha-blockers, and some antidepressants can affect the good quality of sleep.

Physical activity before sleep

Physical exercise is well known for the feeling of relaxation and well-being it provides, especially after a grueling workout. Nevertheless working out before sleep may not be good for sleep. Indeed, this is not very known because it is counter-intuitive but doing sport just before bed can cause insomnia (especially if you make a lot of effort).

During your sleep, the temperature of your body drops. While when you exercise, it increases. Therefore, by practicing a sports activity shortly before bedtime, the temperature of your body will be high and you may have trouble falling asleep.

Moreover, during physical activities, the body releases hormones into the bloodstream that keep us awake and alert. If this is beneficial during a sports session, it can be a problem for your sleep. You may lose long hours of sleep waiting for your hormone levels to drop.

However, a walk before sleep is quite recommended.

Intellectual activity before sleep

In the evening, it is really not the time to make your brain think and it is neither a good time to tackle the issues that get angry if you want to have a good night's sleep. 

The risk of doing an intellectual activity before sleeping is to fail letting your ideas go and that your brain unconsciously tries to solve your problems before sleeping. And that’s what you want to avoid because it will annoy you and further delay your sleep. 

Prefer relaxing activities that don’t need your brain to think.

The culture and the country where you live 

Living in a stressful environment (eg. job, social, politic, economic) determines our pace of life and the environment in which we live. So many factors that are beyond our control can negatively affect our sleep.

Your environment of sleep 

Sleeping in a quiet, dark room and at a cool and comfortable temperature will help you sleep faster. 

When you start to fall asleep the temperature of your body drops and the temperature remains low while you sleep. The body becomes more sensitive to high temperatures and it can disturb your sleep very easily. That’s why the ideal room temperature for sleep is between 18 - 22 Celsius degrees (64.4 - 71.6 Fahrenheit degrees).

Noise, as well as blue light, delays the release of melatonin, the hormone responsible for your sleep. It is therefore essential to cut the noise as much as possible before going to bed. Don’t listen to any sound higher than that of a human conversation. For example, if you listen to music or television, listen to it at a reasonable volume.

Also, the comfort of your bed can influence your sleep. The greater the feeling of comfort, the better the sleep can be.

Pain and Sickness

It is obvious that physical pain and sickness can negatively influence the quality of your sleep and can cause sleep debt. Practice relaxation techniques, such as deep abdominal breathing. In extreme cases, you can use melatonin, painkillers and/or sleeping pills under the supervision of a doctor.

The Full Moon

Scientists have reported an average of 25-minute decreasing sleep time during the Full Moon coupled with less deep sleep. They also found an increase in the duration of REM sleep of 30 minutes during the Full Moon. During this lunar phase, the release of melatonin decreases. In recent years, specialists accumulate the results in favor of lunar influence on sleep, even if failing to have solid tracks of explanations.


Indeed, there are many external factors that can disturb our sleep. But most of them can easily be fixed once you have identified them. If there are several things, do not try to fix everything at once, this is not the right method. Go little by little.

If you feel that you have issues sleeping because of stress or anxiety, you can read “How to get rid of stress and anxiety”

Amaury Kosman

CEO of Circular, Amaury is all about technology and human capabilities improvement. He is a dedicated marathon runner and loves optimizing his training.

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