Put out the light: scientists have told how artificial lighting affects health

Modern man is constantly under the influence of different lighting sources. These are lamps that we turn on at any time of the day, street lights, TV screens and smartphones. We don't even think about how excess light can affect our health. But scientists have already calculated how a violation of light dosing can harm the body.

The lighting mode in which a person lives affects the circadian rhythm of a person, that is, what some call a biological clock. In addition, bright indoor lighting in the evening and at night disrupts the carbohydrate balance. Because of this, obesity can even develop and, as a result, cardiovascular diseases.

So if someone is worried about the problem of excess weight, then you can calm yourself by saying that it's not the food that's to blame, but the wrong lighting. But seriously, the problem has long been considered very serious in the scientific world. In addition to an excess of artificial light, people lack the usual daylight. It also doesn't make us healthier.

We have to spend the whole day indoors, under artificial light, in the office, in the production shop or in the apartment. No high-quality lamp will replace the normal dose of sunlight that we get when walking down the street. The problem required serious research, which was conducted by scientists from the Netherlands.

The purpose of the scientific work was to determine the light source best suited to a person in the morning, afternoon and evening. The options were considered from the point of view of those circadian rhythms and metabolic processes in the body. The University of Maastricht involved 14 volunteers aged 40 to 75 years in the experiment. All these people suffered either from excess weight or from insulin resistance.

During the study, everyone was placed in a special chamber. There was installed equipment measuring the amount of inhaled and exhaled oxygen. These measurements help to calculate energy expenditure and metabolic rate. The subjects were in the cell for two days. At the same time, the intensity of illumination changed.

In the first case, a bright light was turned on in the cell during the day, and in the evening and at night, from 18 to 8 o'clock, dim. In the second, a bright light was on during the day, and the dim light was turned on from 18 to 23 hours. In the third, dim light was turned on during the day, and bright in the evening. Each day, participants were fed three times, ensuring a sufficient level of calories.

Four hours after each meal, the doctors took a blood test from the participants of the experiment. The content of insulin, melatonin, triglycerides (fats) and glucose was studied both on an empty stomach and immediately after a meal. The result was quite predictable. The best blood parameters in people were under the regime when bright light shone during the day and dim in the evening.

At the same time, glucose levels in the blood decreased in all participants before dinner, which is considered the norm. After eating in the right light, people experienced a surge of energy and increased metabolism. In general, the body worked as provided by nature for a healthy person.

But when it was the other way around, and the light was dim during the day, and bright in the evenings, the body showed the worst condition. After eating, metabolism was reduced, as was energy consumption. The production of the hormone melatonin, responsible for regulating sleep cycles, was also disrupted. In dim evening light, 2-4 hours before bedtime, its content in the blood increases. But when the lighting was not working properly, this did not happen.

Scientists from The University of Maastricht came to important conclusions. It is important for a person who is indoors all the time to increase the level of lighting during the day. During the day, it is advisable to find time for walking on the street. Before going to bed, it is advisable to have as little contact with bright light sources as possible, including gadgets.