Recent studies presented at the 62nd Annual European Society for Paediatric Endocrinology Meeting have raised concerns regarding the potential influence of screen-induced blue light exposure on children's growth and development. Continuous exposure to blue light from devices like smartphones and tablets can accelerate bone growth and cause early puberty in rats, according to research at Gazi University in Turkey. These findings point to a potential relationship between increased screen time in youngsters and the recent reduction in the age of puberty onset.

The study divided 36 young rats into three groups and exposed them to either normal light, six hours of blue light, or 12 hours of blue light daily until they developed puberty symptoms. Rats exposed to blue light grew quicker, particularly in their bones, than those under ordinary light circumstances. The primary researcher, Dr. Aylin Kılınç Uğurlu, stated, "This is the first study to show how blue light could potentially influence physical growth and development, prompting further research into the effects of modern screen exposure on children's growth."

The researchers discovered that higher blue light exposure caused early maturation of the growth plates—areas of cartilage at the ends of long bones that control bone growth. The doctor said, "Our study found that blue light exposure led to earlier structural changes in the growth plates of the rats' bones, suggesting an impact on long-term bone age." Despite the rapid early growth, premature growth plate closure may result in shorter adult height.

The findings of a recent study on blue light exposure and early puberty reflect a noteworthy trend of falling puberty onset ages during the last three decades. Data from several studies show that both girls and boys are entering puberty at younger ages than before.

For girls, the average age of breast development, known as thelarche, has decreased dramatically from 10.8 years in 1997 to 9.4 years in 2010. Similarly, the commencement of menstruation (menarche) has shifted earlier, from 12.5 to 12.1 years in the same time frame. We have also observed a significant increase in early puberty cases, with the prevalence of thelarche before the age of eight growing from 5% in 1991 to 18% in 2012.

Boys have demonstrated comparable patterns. The age when genital development (gonadarche) begins has dropped from 11.5 years in 1997 to 10.4 years in 2010. The commencement of pubic hair development (pubarche) has also accelerated, reducing from 12.1 to 11.3 years. The prevalence of early gonadarche (before age 9) has increased from 2% in 1980 to 10% by 2014.

Experts believe that lifestyle factors like increasing screen time and blue light exposure, as well as food, obesity, and environmental endocrine disruptors, could influence these patterns, which reflect a broader movement towards faster physical maturity.

Global reports on these changes attribute the decline to a number of factors, including obesity, dietary changes, increased exposure to endocrine-disrupting chemicals (EDCs), and possibly increased screen time and blue light exposure.

The data show that excessive screen usage during critical growth phases may contribute to early puberty. The doctor warned, "While our study was conducted on rats, it highlights the need for further research to understand the potential effects of prolonged screen exposure on children's growth and development." 

Future research will look into the long-term consequences of pre-pubertal blue light exposure on skeletal development, with the goal of developing guidelines for children's screen safety. Given the growing prevalence of early puberty and its accompanying health hazards, such as shorter adult stature and potential psychological consequences, knowing the influence of screen usage is critical.