Can Blue Light Affect Puberty? Here’s What Early Research Has Found – Healthline
- Researchers are trying to understand why some children are going through puberty at an earlier age
- One theory is that blue light from devices may affect melatonin that could increase the risk of early-onset puberty.
- A new rodent study looked at that possiblity, but experts say more research is needed.
Researchers are trying to figure out if exposure to blue light emitted by electronic screens could increase children’s risk of early onset puberty, and might even damage their future fertility.
Now new research presented at the 60th Annual European Society for Paediatric Endocrinology meeting found that rats exposed to blue light underwent puberty earlier.
Dr. Rebecca Fisk, a pediatric hospitalist at Lenox Hill Hospital in New York, told Healthline, that blue light is a part of the visible light spectrum that is emitted by the sun.
“Which in fact is where we get most of our blue light exposure,” she continued.
According to Fisk, artificial sources of blue light include LED and fluorescent lights, and electronic devices like smartphones, televisions, e-readers, video game consoles, computers, and tablets.
Researchers say they are investigating if there is a link between blue light exposure and reduced melatonin levels. And looking for evidence if increased screen time for children may play a role in this increase.
According to the study authors, melatonin levels are higher during pre-puberty than in puberty. As a result, high levels of melatonin may be a factor in delaying the start of puberty.
Researchers observed 18 female rats to investigate the effects of blue light exposure on reproductive hormone levels and the time of puberty onset.
The animals were separated into three groups; one exposed to a normal light cycle, while two were exposed to 6 or 12 hours of blue light each day.
In both groups exposed to blue light, puberty occurred significantly earlier than expected. The rats exposed to blue light longest were most affected.
Rats with 12 hours of exposure to blue light also showed signs of cell damage and inflammation in their ovaries. The animals were also found to have lower melatonin levels.
“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,” study author Dr. Aylin Kilinç Uğurlu said in a statement.
Fisk explained that melatonin is a hormone produced by the brain in response to darkness.
“It is made mainly in the pineal gland; a small amount is made in the retina,” she said. “It aids with the timing of one’s circadian rhythms, our 24-hour internal clock, and also with sleep.”
She emphasized that exposure to light at night can block melatonin production.
“Any type of light can suppress melatonin secretion,” noted Fisk.
More study is needed to determine if these effects seen in rats would be applicable to humans.
“It is possible that disrupted melatonin, or perhaps more generally, disrupted sleep and sleep stages from blue light, can have an impact on child development,” confirmed Dr. Alex Dimitriu, double board-certified in Psychiatry and Sleep Medicine and founder of Menlo Park Psychiatry & Sleep Medicine and BrainfoodMD.
He added that the limitation of this study is how well these effects would generalize from rats …….