4 ms·

Puberty Starts Earlier Than It Used To. No One Knows Why

24 points by kumaranvpl 4y ago

oversocialized 4y ago
Crabber 4y ago
Puberty starts earlier than it used to *for girls*. Which surely points towards plastics and phytoestrogens in food as being the much more likely cause than improved nutrition or obesity which would affects both boys and girls equally.
- metadat 4y ago
  > Which surely points towards plastics and phytoestrogens in food as being the much more likely caus How are you so confident about this maybe-correlation? It seems FUDish and overconfident without the data to back it up. All we can say for now is that we don't really know why the average age is on the decline. There are a lot of variables.
  - Crabber 4y ago
    We have known that certain plastics mimic estrogen in the body for well over 10 years now. BPA is banned for use in baby products in most western countries for this exact reason, but is still present in thermal receipts and the majority of food and drink cans.
    - metadat 4y ago
      Thanks for the clarification, Crabber.
- deleted 4y ago
  [deleted]
NickRandom 4y ago
Arm-chair Quarterback statement is about to follow - Better (different?) nutrition definitely plays a role (see disclaimer) but it also lead me to wonder if the issue affecting the Californian Condors could be a factor [See 1]. As apex predators they have elevated levels of endocrine-disrupting chemicals. Since we (humans) are also pretty much an apex predator across a wide range of species it is an almost certainly we have the same sorts of problems [1] "A New Study has found contaminants that were banned decades ago are still imperilling critically endangered California condors" (https://newscenter.sdsu.edu/sdsu_newscenter/news_story.aspx?sid=78779 https://newscenter.sdsu.edu/sdsu_newscenter/news_story.aspx?...)
aaron695 4y ago
outsidetheparty 4y ago
I had distinct memories of HGH in milk having been identified as the cause of this, but apparently that has been disproven: https://www.nytimes.com/2005/03/08/health/the-claim-hormones-in-milk-cause-early-puberty.html https://www.nytimes.com/2005/03/08/health/the-claim-hormones... It's a bit startling how quickly it seems to be advancing, though: this 2005 article is saying girls were becoming pubescent "between 9 and 10, roughly a year early". It's only taken a couple decades for that to have turned into "...mostly of girls who were developing breasts at 7 or 8 years old" and "as early as 6 and 7"
Shadonototra 4y ago
https://en.wikipedia.org/wiki/Endocrine_disruptor https://en.wikipedia.org/wiki/Endocrine_disruptor hyper-industrialization of the food industry is the reason why you are, and as a species you become something based on what you eat you change what your species used to eat, you evolve into something else that's chemicals and how evolution works
- feoren 4y ago
  > you change what your species used to eat, you evolve into something else That is definitely not how evolution works. First of all, evolution doesn't happen noticeably over one or two generations, which is the timeline we're talking about here. Secondly, show me how something affects fecundity or survival before we can even begin talking about its affect on evolution.
  - aaaaaaaaata 4y ago
    Survival is not a requirement. Random chance is fine.
    - aaaaaaaaata 4y ago
      Improved* survival is not required
    - feoren 4y ago
      You seem confused. Random chance for what? Affecting what? If not survival or fecundity, what is it affecting? If an effect is completely random, it cannot drive evolution, because it is not a force for selection of particular traits over other traits. What are you talking about?
  - deleted 4y ago
    [deleted]
goodmattg 4y ago
my hypothesis: iced coffee
reducesuffering 4y ago
Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race by Shanna Swan, PhD https://www.amazon.com/Count-Down-Threatening-Reproductive-Development/dp/1982113677/ https://www.amazon.com/Count-Down-Threatening-Reproductive-D...
kurupt213 4y ago
Overcrowding. This is a known biological response to overcrowding. I’m sure all the endocrine disrupters in the water supply don’t help.
- tuatoru 4y ago
  Why does it also happen in low-density rural areas?
  - kurupt213 4y ago
    I think you need to look at ‘low density’ and compare it to historical (Paleolithic) population density. It must be a stress response, so even lower density areas feel some of the pressures of overpopulation (resource scarcity, etc). And I really think that endocrine disrupting chemicals can’t be ignored (but I’m studying analysis of complex environmental samples for my PhD so I’m biased)

24 points by kumaranvpl 4y ago

Puberty starts earlier than it used to *for girls*. Which surely points towards plastics and phytoestrogens in food as being the much more likely cause than improved nutrition or obesity which would affects both boys and girls equally.

metadat 4y ago
> Which surely points towards plastics and phytoestrogens in food as being the much more likely caus How are you so confident about this maybe-correlation? It seems FUDish and overconfident without the data to back it up. All we can say for now is that we don't really know why the average age is on the decline. There are a lot of variables.
- Crabber 4y ago
  We have known that certain plastics mimic estrogen in the body for well over 10 years now. BPA is banned for use in baby products in most western countries for this exact reason, but is still present in thermal receipts and the majority of food and drink cans.
  - metadat 4y ago
    Thanks for the clarification, Crabber.
deleted 4y ago
[deleted]

NickRandom 4y ago

Arm-chair Quarterback statement is about to follow - Better (different?) nutrition definitely plays a role (see disclaimer) but it also lead me to wonder if the issue affecting the Californian Condors could be a factor [See 1]. As apex predators they have elevated levels of endocrine-disrupting chemicals. Since we (humans) are also pretty much an apex predator across a wide range of species it is an almost certainly we have the same sorts of problems [1] "A New Study has found contaminants that were banned decades ago are still imperilling critically endangered California condors" (https://newscenter.sdsu.edu/sdsu_newscenter/news_story.aspx?sid=78779 https://newscenter.sdsu.edu/sdsu_newscenter/news_story.aspx?...)

aaron695 4y ago

outsidetheparty 4y ago

I had distinct memories of HGH in milk having been identified as the cause of this, but apparently that has been disproven: https://www.nytimes.com/2005/03/08/health/the-claim-hormones-in-milk-cause-early-puberty.html https://www.nytimes.com/2005/03/08/health/the-claim-hormones... It's a bit startling how quickly it seems to be advancing, though: this 2005 article is saying girls were becoming pubescent "between 9 and 10, roughly a year early". It's only taken a couple decades for that to have turned into "...mostly of girls who were developing breasts at 7 or 8 years old" and "as early as 6 and 7"

Shadonototra 4y ago

https://en.wikipedia.org/wiki/Endocrine_disruptor https://en.wikipedia.org/wiki/Endocrine_disruptor hyper-industrialization of the food industry is the reason why you are, and as a species you become something based on what you eat you change what your species used to eat, you evolve into something else that's chemicals and how evolution works

feoren 4y ago
> you change what your species used to eat, you evolve into something else That is definitely not how evolution works. First of all, evolution doesn't happen noticeably over one or two generations, which is the timeline we're talking about here. Secondly, show me how something affects fecundity or survival before we can even begin talking about its affect on evolution.
- aaaaaaaaata 4y ago
  Survival is not a requirement. Random chance is fine.
  - aaaaaaaaata 4y ago
    Improved* survival is not required
  - feoren 4y ago
    You seem confused. Random chance for what? Affecting what? If not survival or fecundity, what is it affecting? If an effect is completely random, it cannot drive evolution, because it is not a force for selection of particular traits over other traits. What are you talking about?
- deleted 4y ago
  [deleted]

goodmattg 4y ago

my hypothesis: iced coffee

reducesuffering 4y ago

Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race by Shanna Swan, PhD https://www.amazon.com/Count-Down-Threatening-Reproductive-Development/dp/1982113677/ https://www.amazon.com/Count-Down-Threatening-Reproductive-D...

kurupt213 4y ago

Overcrowding. This is a known biological response to overcrowding. I’m sure all the endocrine disrupters in the water supply don’t help.

tuatoru 4y ago
Why does it also happen in low-density rural areas?
- kurupt213 4y ago
  I think you need to look at ‘low density’ and compare it to historical (Paleolithic) population density. It must be a stress response, so even lower density areas feel some of the pressures of overpopulation (resource scarcity, etc). And I really think that endocrine disrupting chemicals can’t be ignored (but I’m studying analysis of complex environmental samples for my PhD so I’m biased)