Un new study shows that just one hour of exposure to a blue night light increases blood sugar levels and consequently its consumption.
When I speak of blue light I mean the type of light produced by the displays of all types, including mobile phones.
The study, carried out by Anayanci Masís-Vargas and colleagues from the universities of Strasbourg and Amsterdam, was presented this week at the company's annual conference on the study of ingestive behavior (SSIB) in Utrecht, the Netherlands.
Previous research has shown a strong connection between obesity and artificial light levels at night. Much of the light that hits our eyes is connected to LED sources and displays, which emit high levels of blue light. The photoreceptors of the eye are very sensitive to this frequency and directly send the stimuli received to the brain areas that regulate the appetite.

In his studies, Masís-Vargas and colleagues exposed guinea pigs to blue light. They did this by measuring food consumption and glucose tolerance throughout the following day. The accuracy of the experiment was almost manic: the rats used in the study are daytime, stay awake during the day and sleep during the night. The authors observed that after just one hour of exposure to blue night light, glucose levels are completely altered.
What exactly happens?
The researchers tried to understand better what happens to appetite and food choices after exposure to blue light. Guinea pigs were therefore given the choice between standard balanced foods, water, lard and sugar water. After the first phase, the researchers observed a huge growth in the consumption of sugar water by guinea pigs exposed to blue light compared to those not exposed.
In other words, the study clearly shows how much damage LED displays do at night. At least to those who do not filter blue lights. If confirmed in humans, this reactive mechanism is directly related to weight gain and the development of diabetes.
“Limiting the time spent at night in front of the screens is the best way. We must protect ourselves from the harmful effects of blue lights: for those who find themselves forced to exhibit, I recommend the use of apps that filter the light. There are several available ".