The following is excerpted from an online article posted by SceinceAlert.
Among the laundry list of health problems COVID has inflicted on the world’s population, one of the more perplexing could be an increase in the number of girls experiencing what is known as idiopathic precocious puberty – abnormally early onset of puberty.
Precocious puberty for girls is defined as signs of secondary sexual characteristics emerging before the age of eight. Just how many girls that encompasses is difficult to say with confidence as measures of the condition’s prevalence vary considerably around the world.
More than one study has spotted the spike in numbers during the early months of the pandemic of what is typically a rare condition, highlighting a potential link between the virus and a trigger for early adolescence.
Now a study presented at the 60th Annual European Society for Paediatric Endocrinology Meeting in Rome suggests it might not have anything to do with the infection at all. Rather, the time spent during lockdowns scrolling through smart devices for hours on end could be to blame.
Researchers from Gazi University and Ankara City Hospital in Turkey exposed 18 immature female rats to a spectrum of light predominantly emitted by our LED screens for relatively short or long periods each day, finding those bathed in the blue-tinged light for longer bouts showed the hallmarks of maturity sooner than the rest.
“We have found that blue light exposure, sufficient to alter melatonin levels, is also able to alter reproductive hormone levels and cause earlier puberty onset in our rat model. In addition, the longer the exposure, the earlier the onset,” says endocrinologist and lead author Aylin Kilinç Uğurlu from Gazi University.
The reasons for the early surge of hormones are also something of a mystery. Putting aside forms of cancer or other disorders of the nervous system, a good proportion are idiopathic, meaning there’s just no obvious cause.
So when the number of girls reporting an idiopathic form of precocious puberty in Turkey jumped from 25 in April 2019 to 58 in March 2020, researchers were stumped, proposing anything from high-calorie foods to the fear of the pandemic might be to blame.
One intriguing possibility was the stark rise in the use of smart devices. Or, to be more precise, a significant increase in time spent exposed to the blue light emitted from our phones and tablets each day.
Using rats as a more convenient test subject, the team of researchers demonstrated this hypothesis could have a lot going for it.
Not only did the female rats exposed to double the duration of blue light each day undergo their rodent version of puberty at a relatively younger age than their peers, they also had lower melatonin levels and higher levels of the reproductive chemical signals oestradiol and luteinizing hormone.
“As this a rat study, we can’t be sure that these findings would be replicated in children, but these data suggest that blue light exposure could be considered as a risk factor for earlier puberty onset,” said Uğurlu.
This research was presented at the 60th Annual European Society for Paediatric Endocrinology Meeting.