Study links blue light from smartphones or tablets to early puberty | Hacker News Reader

Study links blue light from smartphones or tablets to early puberty

medicalxpress.com

44 pointsclumsysmurf36 comments

Every time people talk about "Blue light" it's a problem precisely because it's like the light we get from the sun, it mucks up our circadian rhythm and keeps us awake. Or it's bad for our eyes because reasons, even though "there is no good evidence that filtering blue light with spectacles has any effect on eye health, eye strain, sleep quality or vision quality" (Wikipedia).

So if tablets do the same thing the sun does and keep us awake, that must mean kids in very sunny areas have early puberty as well? Those up in the tropics with a consistently large amount of sun year round, for example?

Even simple logic deduction, this story makes no sense. And when the truth comes out, it'll probably be something like "Exposing rats to the equivalent of 20 suns worth of blue light causes early puberty and death"

Puberty age in tropical regions is lower. As you near the poles, it gets higher. This is why people in higher latitudes are longer in average. Growth hormone’s release slows down when puberty is reached.

> are longer in average

When you write this people think about genital length. I've done that mistake as well, easy to make as a non native speaker, to get the right point say "taller" not "longer".

Yeah, I moved to an english speaking country in my teens, boy did I make the girls giggle when I made that mistake. It took me a year to figure out why.

Specifically "taller on average".

Even if the blue light from electronics had any significant effect, my first instinct would be to say, it's a wash: the amount of time spent with such electronics correlates strongly with amount of time spent indoors and away from sunlight. If anything, this would be bringing us closer to status quo from 50+ years ago.

Tropical regions are also relatively poorer, compared to more northern countries. And poverty during childhood is related to earlier puberty [1].

[1] https://ifstudies.org/blog/poverty-and-early-puberty-in-aust...

So, there is another way to explain what we see.

> there is no good evidence that filtering blue light with spectacles...

That's likely referencing this recent review[1]. The products referenced don't actually reduce blue light by much, which you can confirm in the studies. The lenses look transparent, not amber in many cases. Which makes sense because they're meant for all day use, but it's just a marketing thing.

If you bought glasses in person in the last 10 years, they probably tried to upsell a blue light or "screen strain reduction" filter.

It's a stretch to hold this as evidence that blue light doesn't affect us.

[1] https://doi.org/10.1002/14651858.CD013244.pub2

Used to have extreme migraines. Any exposure to Fluorescent light would leave me mentally disabled within 10 minutes. So I could enter any grocery stores. Or go into work. Blue light filter glasses did little to nothing.

I got some FL-41 glasses that covered top and sides. I would be fine for about 2 hours under those lights. Eventually light leakage would get to me. But it made a drastic difference.

Fascinating, I would have thought it was the flickering of fluorescent that was getting you. I know CGA / EGA monitors with 60hz refresh rates really bothered me and gave me headaches and it was miserable to program at that time for me. It’s interesting that FL-41 glasses help you, I’m glad to hear you’ve found something that helps. That sort of pain awful and functionally frustrating.

"...in male rats" would be a key phrase to add to the title.

As an important consideration, rats are usually considered nocturnal animals. They are less active when there is light out.

But how did they teach the rats to use a tablet?

Nah, its the extra hormonal load from the early exposure to porn.

Is there a lot of rat porn?

i wouldn't say ive seen "a lot", but it's not unknown...

Um, I think those were gerbils.

Do you have any links to scientific studies that found this effect?

10 year old girls watches porn to such a degree it affects their hormones? Obesity is the main suspect so far, but maybe it is blue light, we don't really know. But we can be pretty sure it isn't porn, since it affects young girls to such a high degree.

https://www.nytimes.com/2022/05/19/science/early-puberty-med...

Good article (I remember reading that one when it first came out)—not only does it seem to disproportionately affect young girls, but it also seems to affect American kids more than kids from any other country.

Years ago I remember hearing it was due to growth hormones we feed livestock. Wonder if that's been debunked.

I believe this is talking about a peptide hormone injected into cows. Being a peptide, if you ingest it it will be digested. It's the same reason insulin is injected, not administered orally.

It would be interesting to see data of how much blue light an individual is exposed to proportional to their smartphone use. I would expect people who are regularly outdoors would use their smartphones less due to the difficulty of seeing the screen under the enormous blue light reaching from horizon to horizon.

another worthless study to add to the pile

My optometrist was quite skeptical of various claims about blue light & blue light blocking glasses, for example...

I've noticed people who start wearing blue blockers can no longer attract a mate..

My optometrist was quite skeptical of that anyone can cure their myopia. Yet I’m doing exactly that with measured improvement.

Oh, do tell ...

Start here: https://www.youtube.com/watch?v=XPIGDSY_xBs

Is that the ancient Chinese way of sleeping with stones on the eyes, to flatten the lenses?

Myopia is the cornea slowly becoming football shaped instead of round. While the effects can be lessened through various methods, the myopia will indeed eventually overcome such methods.

Can’t make a football into a soccer ball without surgery.

Ahem ahem, that is the theory, yes. Not what I and many others are seeing practically. See: https://www.youtube.com/watch?v=XPIGDSY_xBs

Ophthalmology is not so much /theory/ as over 100 years of study, discourse, research, and practical application.

What you're proposing is /theory/ with few actual studies, research, or practical applications beyond some few people 'trying' something new.

Again, you may be able to lessen the football shaping with various methods. But at the end of the day, the body wants it to be a football, and you want it to be a soccer ball. Guess which of those competitors wins?

I understand what you're saying. I was just stating my practical experience. I'm not arguing anything here. My eyes are healing with visible and measured improvement, and I cannot care less about which theory matches reality, or what any theory out there says about what should and shouldn't happen.

in the USA, medical guild members are trained to ignore non-guild member theory from the very first year of specialization IMHO.. secondly, there are legal consequences for those that do not adhere to guild doctrine, or could be exposed to legal threat.. IMHO medical guild information is conservative often, but surpasses simple science when pressed in controversy.

The blue blocking lens addition that's sold for regular glasses is very dumb, your optometrist was correct. First, you want blue light during the day so why would you want to have that on glasses you wear all day? And two, they don't block nearly enough blue light to make a difference at night. You need the very orange tinted safety glasses for that. Those absolutely do work.

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