Massive health damage with continuous light

What happens when people are exposed to a constant light source??
Daylight is the most important light source on our planet. The light influences, for example, animals and plants but also the mood of people. What effect does it have when exposed to a constant light source? Researchers now found that constant exposure to light not only disrupts the circadian rhythm, but also diminishes skeletal muscle function.

Researchers from the Leiden University Medical Center in the Netherlands found in an investigation that a constant light exposure leads to disruption of our circadian rhythm and even causes a reduction in the function of skeletal muscle. The physicians published the results of their study in the journal "Current Biology".

What effects does it have on our health when exposed to a constant light source? Do animals and humans really need a chiaroscuro cycle? (Image: karandaev / fotolia.com)

Light-dark cycle is important for humans and animals
The results of the new study underline the importance of the so-called day-night cycle (light-dark cycle). This is important for the health of humans and animals, explains the author Dr. Johanna Meijer. If this important cycle is disrupted, it will have a negative impact on health.

Study exposes mice to a constant light source over months
During the new study, mice were exposed to a constant light source for several months. This constant exposure to light disturbs the brain activity of the animals, explain the Dutch experts. The normal rhythmic patterns of the so-called central circadian pacemaker of the suprachiasmatic nucleus are reduced by up to 70 percent. In addition, the disruption of the normal light-and-dark pattern and circadian rhythm also reduced the skeletal muscle functions of the animals, the researchers add.

Constant light damaged the bones of the mice
The effect of changing the light-dark cycle was clearly visible. The bones of the mice became weaker and the animals developed a pro-inflammatory condition, say the doctors. This is usually only observed in the presence of pathogens or other deleterious causes of the disease.

Negative effects regenerate quickly
After the mice had lived with a standard light-dark cycle over a period of two weeks, the brain cells recovered rapidly and the animals' health problems regenerated.

Missing light-dark cycle leads to disturbances of health parameters
The study clearly shows that a lack of environmental rhythm leads to severe disorders of a variety of health parameters, the authors explain. These disorders included, for example, inflammatory response by the immune system, muscle loss and early signs of osteoporosis. These physiological changes are usually all typical of the frailty that usually occurs in aging humans and animals, Dr. Meijer.

The amount of light exposure of humans should be better considered
The good news is that these negative health effects are reversible when the normal light-dark cycle is restored. Meijer. With light bulbs and fluorescent lamps in our offices, it is now possible for us to spend virtually the whole day without any existing darkness. The current results suggest that in the future more attention should be paid to the amount of human exposure. Especially of old and sick people, the authors add.

Certain occupational groups are exposed to a great deal of light
About 75 percent of the world's population are also exposed to a light source during the night, the scientists estimate. For example, 24-hour lighting is completely normal in many nursing homes or intensive care units. The patients there, as well as active nurses, doctors and nurses are thus exposed to a constant source of light.

Humans and animals rely on a light-dark cycle
It used to be thought that light and darkness are only harmless or neutral stimuli to our health. Meijer. However, based on the results of the study, it can now be seen that this is by no means the case. Humans and animals seem to be optimized to live with a light-dark cycle. Of course, the disadvantage is that it can also have negative effects if there is a lack of such cycles, the scientists add. (As)