It shines, but does not warm: what’s wrong with the bright light in the evening

It shines, but does not warm: what's wrong with the bright light in the evening

Children, especially preschool children, are often afraid of the dark, so they ask their parents if they do not leave the light in the room for the night, then at least leave the door open. In this sense, a night light becomes a real find, it illuminates the room enough that the child is not afraid, but at the same time extremely soft, so as not to interfere with his sleep. But is this only the case?

A new study published by Physiological Reports shows that bright electric lighting in the evening almost completely suppresses the production of melatonin in preschool children, which is an important addition to the growing volume of research in this field. Recall that melatonin is a hormone that is extremely important for normal biorhythms and healthy sleep. In other words, parents should pay attention to the intensity of light not only when they fall asleep, but also a few hours before.

But in addition to the fact that bright evening light can cause problems with the quality of sleep, it can also provoke health problems in the long run.

Light pollution

As reported by The Conversation, the new work was based on a previous study, published in 2015 by The Journal of Clinical Endocrinology & Metabolism, in which children and adolescents aged 9-16 took part. Then scientists reported greater sensitivity to light in young children, compared with older children. In the course of fresh experiments, it was concluded that, since the use of smartphones today is extremely common in children (even preschool age), circadian effects can be significant here.

There are at least three reasons why a large amount of light during the evening can make a difference to the health of children. And they sound pretty frightening: depression, suicide and cancer. The fact is that light is a part of what experts call “light pollution”. And this problem, which you may never have thought of, is becoming more and more widespread in the modern world.

Depression and not only

Jean Twenge, who studies mental health and social adaptation among young people (mostly among those born after 1995), says that the situation is more serious than it seems at first glance. In her studies, she found a link between the time of new media (in particular, smartphones) and the risk of depression and suicide in adolescents.

Twenge suggested that the reasons should be sought not only in social isolation, but also in the lack of sleep. The latter, as the following studies allowed to say, should be linked, among other things, with the increase in the time of use of the smartphone (including in the evening) and, as a consequence, the deterioration in the quality of deep sleep.

Culprits, obviously, can be ordinary bulbs in the room. A bright light, if it is turned on until you go to bed, slows down the body’s transition to the pre-nasal phase, which is best at twilight.

The risk of cancer, which is still in question

The basis for concern is the fact that untimely electric light can disrupt the child’s circadian rhythms, which in turn can be associated with an increased risk of cancer in adulthood. But, for the sake of justice, such statements do not yet have sufficient evidence.

At one of the conferences of the charitable organization Children with Cancer UK, they also talked about leukemia, the most common cancer disease in children. It is characterized by the uninhibited growth of white cells in the blood, which are usually generated by stem cells in an amount sufficient for a healthy immune system. A recent study on the topic showed that the division of stem cells is under daily control. That is, the abundance of light at night can in some sense destabilize their work. However, to say this for certain, there are still a lot of case studies to be carried out.