Every day we are exposed for hours and hours to the blue light emitted by our mobile phones or computers. Now, this concern is not new, but an experimental study shows, for the first time, that this exposure may pose risks to children’s development and their future fertility. The hypothesis raised by these results will need further research in the future to prove the stated risks.
We already knew about other possible consequences of this excess blue light in our eyes, such as altered sleep patterns or vision problems. However, results presented now at the annual meeting of the European Society of Pediatric Endocrinology warn that excessive exposure may increase children’s hormone levels and the risk of precocious puberty.
The starting point is all around us: “Using these devices [telemóveis, computadores] among children has increased, and there are publications showing an increase in cases of precocious puberty during the pandemic, compared to the pre-pandemic period”, presents Aylin Kilinç Ugurlu, pediatrician and researcher at Gazi University in Ankara (Turkey).
Early puberty carries health risks as it develops earlier than expected and is also influenced by physical changes early in a child’s life (eg between 8 and 10 years of age). There are other consequences: these children have an increased risk of depression or anxiety, as well as the development of breast cancer, for example.
In order to understand the effects that a child can have with excessive exposure to blue light from screens, a team led by Aylin Kilinç Ugurlu conducted an experimental study on mice to understand the hormonal changes. In what the Turkish researcher claims is the first experimental study conducted in this area, one of the main highlights is the hormonal changes and changes in ovarian tissue in these animals after exposure to blue light – indicating this promotion of precocious puberty.
However, these results cannot be automatically extrapolated. To expose the mice to blue light and simulate exposure to cellphone and computer screens, the researchers used a type of exposure that changed melatonin levels—something that has already been shown to change in some studies of children exposed to blue light.
Melatonin is a hormone produced in our brain that helps regulate various processes in our body, including puberty.
Although the association seems direct, it is not. “It is difficult to extrapolate these data to children because the type and duration of exposure to blue light is not equivalent to what we would see in a child using a normal device,” Ugurlu explains to PÚBLICO. “Although these data are from mice, they highlight that blue light should be investigated as a potential risk factor in this recent increase in cases of precocious puberty,” he adds.
A more common occurrence
The increase in cases of precocious puberty is similar in several countries and, as Ulurgu says, especially pronounced during the Covid-19 pandemic. There are other factors that could enter into this discussion: genetic problems, obesity or a more sedentary lifestyle have already been mentioned.
In Italy, cases of girls with precocious puberty almost doubled between 2019 and 2020, in one of the most cited studies to exemplify the problem. On the other hand, this is not a problem that has been mentioned only in the last two and a half years: already in 2012, this increase compared to the previous decade was mentioned. However, it is still an uncommon phenomenon in the world.
Ulurgu focuses attention on intensifying our contact with electronic devices. “The increased use of these devices, especially at night, increases the intensity and duration of our exposure. Some devices already have options that filter out blue light, which can help reduce the risk – but more research is needed [para o confirmar]”, Shows.
“The effects of blue light on humans are still under-researched and very difficult to apply. But with this increased incidence of precocious puberty and this association with melanin levels, it is an area that warrants further investigation.” “These results will not necessarily be transferred to children, but the risk is something that must be considered and investigated,” he concludes in response to PÚBLICO.