Sport
Sport We all know that you have to sleep in the dark, but what if there is a little light? It will always be better than a big light bulb, but it still has negative health consequences.

Many people sleep with a few slits of light sneaking through the blinds. Sometimes they do it because they are afraid of the dark, but usually it is a habit that perhaps goes back to their childhood, when they asked their parents not to close the door or turn on a small presence light next to their bed. .
We tend to downplay this custom, but neurologists and chronobiology experts they are blunt when asked:
The best thing for a restful rest is to sleep in absolute darkness. Not doing so ends up taking its toll on health.
The reason must be found in the so-called circadian system, what is it:
The person in charge of organizing all the rhythms that take place in our body; among them, sleep-wake. It is governed by a conductor, which would be our internal clock, and which is located in the part of the brain known as the suprachiasmatic nucleus of the hypothalamus.
This clock, despite having an autonomous operation and genetically marked, does not exactly coincide with the natural 24-hour day. But it has a timer that tells it what time it is, when it’s dawned, if it’s time to sleep, that it’s light. The light information reaches the retina, which sends it to the suprachiasmatic nucleus of the brain, which in turn “converts it into a temporary signal and tells the rest of the body: ‘it is time to sleep’, or ‘it is time to wake up.’”
In all this process plays a fundamental role melatonin, the quintessential hormone of darkness and sleep. Light removes melatonin from the body, with consequent negative results for sleep. Without melatonin, we will not be able to fall asleep or it will be more superficial, fragmented and with more awakenings.
And the more light there is at night, the worse the consequences. It is considered that the more light intensity there are more sleep problems, although it is not a linear association and will depend on the person, especially related to age” In fact, total darkness is important especially in the youngest because They are more sensitive to light.
Sport Health consequences of sleeping with light
- Having insufficient and poor-quality sleep from sleeping with light can have cognitive effects, which mainly translate into reduced attention and the ability to learn new things and memorize them.
- Increased risk of occupational and traffic accidents.
- Artificial light at night has been globally associated with cardiovascular disease, obesity, mental health problems, and cancer.
- If, due to the presence of light, our sleep does not reach deep phases, we do not have the brain repair we need and this, in the long term, has been related to the development of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s.
Sport Tips for sleeping with as little light as possible
Having established that darkness is the optimal way to sleep, it must be borne in mind that for some people it is quite a challenge to do without light completely. In those cases, there are some recommendations that can be very useful. The need for light must be individually assessed to avoid difficulties in children going to sleep or staying in bed or, in the case of the elderly, the risk of falls.
For those cases in which light cannot be totally dispensed with, it is convenient to know the factors that minimize its effects:
- The spectrum of light. Melatonin is mainly eliminated by blue light, which is what most electronic screens emit and is around 460-480 nanometers. A yellowish or orange light is preferable (less harmful).
- The intensity of the light. A low intensity and warm light is convenient.
- exposure time: the less, the better. If a child needs a point of light when they go to bed, it can be turned off as soon as they fall asleep.
- Go to the bathroom with as little light as possible. Be careful with turning on the light to go to the bathroom. It is advisable to keep the most absolute darkness even when going to the bathroom. It has been seen that, if we are sleeping, we get up to the bathroom and turn on the light for a period of 5 or 10 minutes, melatonin is completely eliminated from our body, with which our sleep will be very fragmented and will It will cost a lot to reconcile it.
Sport No night light… but yes when you wake up
You have to take into account the external light that can enter the room and use blinds, blackout curtains, etc. to reduce it as much as possible. However, the ideal would be to be able to sleep in a place where there were no streetlights outside or light pollution, in order to be able to rest with the windows exposed. In this way, the light will fully enter the room in the early in the morning, which is when it is beneficial again.
In order to better synchronize the circadian rhythm, it is important to be exposed to natural light for as long as possible, especially in the early hours of the day. In this sense, the light of the first thing in the morning is fantastic because it is what tells us that it is time to wake up, activate and eliminate melatonin from the body.