The results of a rat study, presented at the 60th annual European Society for Pediatric Endocrinology meeting recently, suggest that regular exposure to blue light from tablets and smartphones may affect hormone levels and increase the risk of precocious puberty.
A longer period of exposure to blue light was associated with an earlier onset of puberty in female mice, who also exhibited decreased levels of melatonin, higher levels of various reproductive hormones, and physical changes in their ovaries. The use of mobile devices that emit blue light is already associated with disturbed sleep patterns in children, but the current findings suggest that there may be additional dangers to fetal development and future fertility.
The increasing use of devices that produce blue light, such as tablets and smartphones, has been linked to sleep quality in children and adults. Blue light slows the rise in melatonin levels in the evening to prepare our bodies for sleep and rest, which is thought to interfere with our body clock.
Melatonin levels are usually higher before puberty than during puberty, which may play a role in delaying the onset of puberty. The complex process of puberty requires the coordination of numerous physical functions and hormones.
Several studies in recent years have found an increase in the onset of early puberty in girls, especially during the COVID-19 pandemic. Increased screen time, such as was experienced during pandemic restrictions, may have contributed to this reported increase, as indicated by the association between blue light exposure and decreased melatonin levels. However, it is quite challenging to assess children.
Dr Aylin Kilinc Uurlu said, “Since this was a rat study, we cannot be certain that these findings would be duplicated in children.” Although simulating the same level of blue light exposure as a child using tablets is challenging in mice, the age at which mice reach puberty is roughly comparable to humans when considering the short lifespan of mice.