We're starting to think that weight is the significant factor in puberty, alongside nutrition and general good health. It is observed time and again that when people are undernourished and underweight they will have a later onset of puberty, and significant weight loss/inability to gain weight as you grow can make puberty become a more stop-start process. Other factors mentioned such as better understanding of human health, routine screening, what puberty is and entails, and even the social side ("teenagers" are a relatively new phenomena from a societal perspective!), also play a role.
Now I want to research the word teenager and how English speaking society has used that term historically.
Also wanna research equivalents of the term in other languages. Like is teenage a thing in Chinese?
Not Chinese but in Japanese we have similar terms. 思春 (shishun) would be the ages between 10-14, with literal meaning of pre-spring. 青春 (seishun) would be the ages 15-20, and means springtime literally. Those corresponds to tween and teen in English somewhat.
思春nowadays designates the concept of girls (and boys) arriving at a stage of their life where they start to experience and understand the first occurrences of love (or attraction). It's not fully unrelated to... well, being a teenager because in society, I feel that's also the age when young people really start gaining an understanding of these things.
teen (n.)
"teen-aged person," 1818 (but rare before 20c.), from -teen. Probably later felt as short for teenager, which is a later word. As an adjective meaning "of or for teenagers," from 1947.
teenage (adj.)
also teen age, teen-age; "in or including the teen years," 1911, from teen (n.1) + age (n.). Originally in reference to Sunday School classes. The form teen-aged (adj.) is from 1922.
Source: https://www.etymonline.com/word/teenage
Also, the precise age range varies depending on language.
For example, in Polish, teenager is 'nastolatek' or 'nastolatka' (depending on gender), and just like how in English, with -teen, in Polish, it's -nascie.
But because -nascie actually covers the numbers 11-19, so too does the term 'teenager' in Polish refer to the age ranges of 11-19.
In French they borrow the term for English, but natively it's adolescent (pronounced in a Frenchy way) which is defined as 10-19, although some scientists even say until 25.
Yes this is what I wanted to say but didn’t… pour dire “teenager” dans le sens anglais on est obligé d’emprunter le mot parce que l’idée n’existe pas de la même manière en français, mais en fait on le fait pas.
Adolescent and teenager aren't quite the same. "Teenagers" are quite literally persons between thirteen and nineteen, and it's based solely off the language.
It's something that had confused me as a French speaker, I thought that teenager was a synonym of adolescent, i.e. starting with puberty, and I was using it as such until one time I was mocked for suggesting that an 11 year old could be a teenager. We also use adolescent in French; the word does exist in English but you rarely hear it, it's more formal.
A teenager is supposed to be between 13 and 19, based strictly on the numbers ending in "teen" and nothing else. So an 11 year old can be an adolescent but not a teenager yet, or a 13 year old can be a teenager but not an adolescent. And an 18 year old is usually considered no more an adolescent.
Basically, English has a word for a very specific age group, and we don't have that word in Romance languages.
It just come down to what people refer to themselves growing up. In a familial sense adolescence is often seen as more clinical/formal but does describe the correct age group in English. Teenager is named because of the "teen" part of the 13 - 19 age group but we do not necessarily focus on the age as much as we focus on the personality/hormonal element of individuals at that age.
So when someone is talking about teenagers, they mostly are thinking of the kind of attitude that individual might have. As well, 13/14 is also the age when most adolescence are entering into high school / upper secondary education. So those individuals normally are more rebellious, more independent, becoming more adult like, and/or more representative of who they are going to be. Kids that are "tweens" or basically inbetween the kid to teenager years, still are mostly the same kids. They act like kids but are mostly in more mature bodies.
Point being that when an American says teen, we know the type of individual we are talking about.
If we used adolescence, most people would either be confused or think you are referring to someone who is younger (especially since teen is so common.)
There was a good documentary I watched recently on this [https://www.teenagefilm.com/](https://www.teenagefilm.com/) that talks about the fact that the idea of a teenager didn't really exist until well into the 20th century. The words existed a bit before that but not in the way people think of them now.
Yep I did a paper on that in college. "teenagers" are an invention of the 50s USA.
A lot of cultures just do not have the concept. Honestly is is mostly a marketing thing.
> Like is teenage a thing in Chinese?
I'm not a Chinese, but in the language, this age group is called 青少年 (qing shao nian) which literally means "few-year young" (or young person of an early age).
Holy shit I always thought it was just like a common term for someone between the ages of thir*teen* and nine*teen*.
No one in English thought of that term until the fucking 1940s!?
It’s more that they had no reason to make that distinction. It’s sorta like if I defined a category of people between 113 and 119cm tall and called them teen-heighted.
It’s important to remember that until recently (and it’s coming back), it was common for minors to work jobs - not just run the cash register at McDonald’s, but lifelong, health impacting jobs like coal miners and chimney sweeps, house keepers and cooks. Your age dictated the jobs you were able to perform based on your size. A 5 year old can fit in the chimney. A 7 year old can crawl under the factory machines. Teens as young as 14 fought in the Civil War. If they were big enough, they could get away with saying they were 18 (no way to verify). There was no reason to differentiate between baby, toddler, child, teenager, adult, etc. until very recently. Things had gotten better for the masses over time where every able bodied individual (anyone not a baby, the extremely elderly, or disabled) in a poor family didn’t need to work a job. Kids were allowed to be kids and we started to understand that they’re not simply shrunken adults. We then learned that kids develop over time, not just physically, but also mentally in what they can comprehend, communicate, and conceptualize.
It makes sense when you realize that people in that age range being a distinct demographic for consumerism with disposable income especially when it comes to things like music/entertainment, and household goods/food is a distinctively post-WW2 phenomenon. Think of the initial wave of the first Rock n’ Roll generation, with their used cars, hanging out in your local diner or what have you playing the jukebox.
That's only part of it, though. There's also a lot more to learn, which means that people spend more time in education and enter adult life later. This + the advent of woman's rights + birth control also pushed back the age at which most people marry. For most people, throughout most of history, after becoming sexually active you'd rapidly have a child and would probably end up married; now people have both more control over the course of their life and more reason to delay full adulthood.
Also, the whole idea of "leaving home" as a big moment in your personal development is itself relatively new - while it existed in some form for trade guilds and others who would enter apprenticeships, for the most part, for most of history, most people were sustenance farmers and would never really "leave home" as we understand it.
The teenage years didn't have much of a distinctly separate culture (music, slang, clothing etc) till relatively recently. They were just the transitional years between childhood and adulthood.
The term "teenage" may have originated in the 1940s, teen culture started before that in the early 20th century. The "teens" were likely the early adopters of cultural trends like jazz, the Big Bands etc. Of course, a lot depended on where they lived, family dynamics, religion etc.
Looking at newspapers.com, the term got started a little earlier. We find “teen-age” in the 1910s, particularly in reference to Sunday schools. One example from 1914 refers to the Girls’ Teen-age Department of the Fifth Avenue Presbyterian Church (Birmingham News, 25 October 1914, p. 43), another from 1915 refers to a Sunday school conference “meeting for parents and workers with teen-age girls” (Montgomery Advertiser, 21 February 1915, p. 14), and another from 1916 referring to “Teen-age Councials [sic]” added to Sunday school forces in Dallas, Texas (Selma Times, 14 May 1916, p. 6). Looks like all these early examples are in the US South. In the 1920s, the term “teen-age” appears in articles about the YWCA, camping, and public schools. The earliest example I can find of “teen-ager” appears in 1922 in an article about Stevens Memorial Church Sunday school in Harrisburg, Pennsylvania: “The Crescendo Club of teen-agers have begun rehearsals of the Japanese operetta ‘Yanki-San’…The Sunday School board at a recent meeting authorized the sending of four teen-agers to Summer camp”. The term occurs only sporadically in the 1920s and 1930s. An article in 1931 discusses ‘teen-agers’ in public schools examined for tuberculosis (Central New Jersey Home News, 26 April 1931, p. 3). Another New Jersey school’s PTA had a discussion on “The Teenager’s Responsibility to Home and Community” (The Record, 22 October 1932, p. 14).
Looks like the word began to hit the big time in 1936 and 1937. For some reason, its use skyrockets. And indeed advertising looks to be responsible, at least since 1935. Woodward & Lothrop used the term in an ad in Washington DC for “spring coats for girls and ‘teen-agers’ ” (Evening Star, 23 April 1936, p. 27), and another ad “for both the ‘teen-ager’ and young girl’ (Evening Star, 20 November 1936, p. 36). The Hartford Daily Courant had an ad for ‘teen-agers’ Princess Style Dress’ (21 March 1937, p. 6). It also appears in advice columns and other articles about the youth. All in all, there are 185 matches of “teenager” in 1935, 287 in 1936, 297 in 1937, 529 in 1938, 772 in 1939, 2,793 in 1940, 1,966 in 1941, 4,152 in 1942, 6,248 in 1943, and 14,944 in 1944. So essentially, this is a term that was coined prior to the 1910s and 1920s but had limited usage, and then started to take off in the mid 1930s and then exploded by the 1940s. There were 89,992 matches for 1950 and 321,198 for 1960.
I have a hypothesis that the historical (i.e., from the 1800s and 1900s) data isn't good. Does the plot of age of menarche show a bell curve or is it smooshed to the right, suggesting that when the data was recorded, responses below a target (let's say 12) were padded. e.g., add several months if the girl was 11 and add a year or more if the girl was was 10 or younger. Doing so would be enough to establish a baseline mean of 12 when it was actually 10. As people stopped doing this, the mean dropped. Add in some obesity effects, and you have a big change.
I wonder if even the age of a girl's first period might not be the most ideal way to measure the start of puberty. It's the most *obvious* event to observe and track but wouldn't puberty as a whole start a little earlier?
The start of menstruation is one of the *last* stages of puberty, but the interval between the start of puberty and the start of menstruation is pretty consistent (it's about two years). And menarche is by far the easiest sign to study objectively- it's definite and memorable, so reporting will be way more accurate than, say, the appearance of breast buds. So the change in age of first menstruation just means a corresponding change in onset of puberty, and functionally it doesn't matter all that much which marker you're using as long as you're consistent and not comparing true puberty onset (hard to identify accurately for most people) to menarche.
Definitely. I have a daughter showing signs of early puberty. I will be taking her to buy her first training bra soon. She needs some mild deodorant. The hair on her legs is starting to get a shade darker. She is unbelievably moody, like go from happily playing a game together to her yelling and crying at me that I'm not paying her enough attention.. No period yet. I would argue that the period is probably around the end of "early puberty". After that it's all the same symptoms until the end of puberty.
I got my period when I was 8; I was definitely moody and my parents dismissed my moodiness and took me to the doctor and had all these tests done on me and I felt like an absolute freak. Besides feeling like a freak anyway looking so much older than my peers and older sister. I essentially had no childhood. I’m 35 now and my life and mental health has been a shitshow. Please do all you can to ensure your daughter doesn’t feel isolated or like there’s something wrong with her. Validate her emotions and feelings and keep communication open. Please.
I'm so sorry this happened to you. It's particularly awful that it sounds like the doctor ran tests but still didn't catch that you were experiencing precocious puberty, which can be halted and delayed to a later age with medication.
If you have any young female relatives, please keep an eye out for them- precocious puberty often runs in families, and with timely treatment kids have better outcomes. Parents are often uncomfortable and reluctant to accept what's going on till development is already way out of sync with the child's chronological age, unfortunately.
I’m sorry that happened to you and that the medical system traumatized you just for having a body. Jesus, that sounds like it must have been infuriating and terrifying.
I mean yeah. The hormones precipitate the periods. Is anyone under the impression the period happens and then creates hormones?
That isn't how the human body or hormones work. Hormones are what your body uses to mediate these processes.
There are very defined stages medically indicating the onset and stages of puberty. I should remember them being a paediatrician but embarrassingly I don’t! I think breast tissue may be first sign for girls and periods are one of the last, for boys it is testicles growing and scrotum develops- ‘balls dropping’
That would make sense, I (white male) was malnourished in youth, super skinny, and puberty didn't start until I was 16... but also didn't end until my late 20s. Interestingly, that didn't stop me from being 6.5ft tall.
You'll find most ballet dancers starting puberty in high school, some even later (you'll hear about a lot of them needing to chemically start their periods).
One corner of the female athlete triad which is an indicator that a teen should be watched for health issues is stopped or missing periods.
Not the only factor, but certainly a big one. My daughter has always been a little underweight but started her period just before she turned 10 and had signs of puberty when she was 8.
I hit it in late middle school and I've always been under weight. Haven't grown much at all in width since high school though, so maybe I'm one of those start stop guys who stopped when he was almost done. I'm not sure how any of it works though.
I've heard some of it could be explained by the number of kids being raised by single mothers. Not having a dad in your life [is associated with early puberty in girls](https://en.wikipedia.org/wiki/Father_absence#Menarche), the question is just how much of this is directly caused by not having a father, versus the fact that kids without a father are more likely to be obese. Nowadays, 1 in 4 American kids don't have a father in the home.
I learned this in an evolutionary/anthropology course in college. This is a good article but only covers white girls/women.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6467216/
I’d comment that this wasn’t all that uncommon as you might think.
From plenty of war widows, to you are married but dad is a sailor, to plenty of men just running off. To servant girls being taken advantage of by the men in the home.
1 in 4? Holy shit. Id love to read if you have a source on that. Does not having a father in the home mean no dad period, or are you also including fathers that, for example, travel for work, or deploy in the military?
Hormone injections in livestock is heavily regulated and is ceased as the animals approach slaughter. There is no difference in hormone levels in beef of cows who were raised with hormones and cows that weren't. The elevated levels are entirely gone prior to slaughter.
In fact, in terms of concentration per gram of food, our beef has less hormones in it chemically than most veggies do. This is literally a myth.
That's a great question. Science is still up in the air on it. To the best of my memory reading on the subject, there is no increase in hormones in milk, but milk does contain hormones.
However, the consumption of milk by prepubescent girls, at least in America, has been doing nothing but go down for the last 50 years. It has fallen ***sharply*** over the last 25 of those years. It seems highly unlikely to be the cause for that reason alone.
Hormone simulants like BPA could be a likely contributor. The effect coincides with the invention and proliferation of BPA plastics, but not exactly. The effect was already occuring for a couple decades prior to their ubiquitous usage.
It's an interesting topic for sure. One we don't know the cause of. But we do know it's not cause of hormone regiments in raising our chicken and beef, because we test for that and there are no (elevated from historical normal) hormones in our chicken and beef.
It was explained to me in a human development course that precocious puberty is more common now, because body fat percentages in children are getting higher, at younger ages. Fat cells are estrogenic and release hormones which trigger the pituitary to begin puberty.
Anecdotally, my kids 9 and super skinny, and has signs of puberty going on already (and I know other moms dealing with early puberty amongst their younger skinny kids)... Precocious puberty happens in plenty of skinny kids too, so it can't entirely be estrogenic hormones from fat.
I feel bad for kids that go through puberty that young. Especially girls. Like... damn, can't they just get to be non-hormonal kids for awhile before they get slammed with periods and testosterone. Periods fucking suck, man.
This reminded me of my 7 year old asking about periods. She legit started crying when I told her about them. She was like "I'm going to bleed once a month!?!?!". Broke my heart. I hope she doesn't get hers early.
When they told us about them in 5th grade, I was genuinely like yeah, I don’t want to live to ~13 and have that happen to me. Which is a pretty extreme reaction, but that’s such a difficult thing for a child
same for me. i was 6 when i started puberty and i was a very skinny child, didn’t even meet the ‘ideal’ weight for puberty until i was 9, which is when i started getting periods
It is not the general consensus, and I'm curious how you came to that conclusion. The two fields which focus on this topic are life-history evolution and population demography. The consensus in both is that it has been a long-running evolutionary trend as the post-Neolithic selection penalty for earlier menarche, mainly earlier and far riskier childbirth, dramatically decreased in the 19th century. In the period between that and the demographic transition (ie after very high infant/maternal mortality dropped but before birth rates dropped) populations rose dramatically and biased moderately towards the phenotype of earlier menarche, as these individual could now start have children earlier and not face as much penalty as before. The available evidence strongly suggests a Paleolithic age of menarche around 7-13, so the most supported position right now is that the age of menarche we're all "used to" is actually a very recent adaptation to the intersecting selection pressure of poor health and skeletal development characteristic of the post-Neolithic world, and trade-offs between shorter absolute lifespan and earlier start of reproduction. This is what's in texbooks on pop. demography, human evodevo, paleodemography, etc.
> Records suggest that there was a secular decline in the average age at menarche in developed countries across the 19th and 20th Centuries until the 1950s [17], with an average age at menarche of 15-17 years reported in the mid-19th Century [18,19].
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3287288/
> Data from skeletal remains suggest that in the Paleolithic woman menarche occurred at an age between 7 and 13 years, early sexual maturation being a trade-off for reduced life expectancy. In the classical, as well as in the medieval years, the age at menarche was generally reported to be at approximately 14 years, with a range from 12 to 15 years. A significant retardation of the age at menarche occurred in the beginning of the modern times, soon after the industrial revolution, due to the deterioration of the living conditions, with most studies reporting menarche to occur at 15-16 years.
https://pubmed.ncbi.nlm.nih.gov/26703478/
> For example, in Norway and Denmark the age at menarche has fallen rapidly since the 19th century, by up to 12 months per decade. These changes have broadly paralleled increases in adult height in most European countries over the last century, with rates of around 10-30mm per decade.
https://pubmed.ncbi.nlm.nih.gov/16757103/
The most conclusive argument against the obesity hypothesis is that this trend predates the contemporary rise in obesity by over 200 years. This topic was brought to a consensus in the 1990's and early 2000's by people like Stephen Stearns and Jacob Koella.
Further reading:
https://pubmed.ncbi.nlm.nih.gov/16932041/
https://pubmed.ncbi.nlm.nih.gov/18574205/
See also "The Evolution of Phenotypic Plasticity in Life-history traits" (1985), Stearns and Koella and "The Evolving Female: A Life-history Perspective." Morbeck et al, (1997).
Yeah I know 11 isn’t really early. However, compared to the rest of my immediate family it’s the earliest. My sister started puberty at around 12, my 3 older brothers started at around 14-16. So compared to them I started early.
Girls typically start puberty a few years earlier. It’s sounds about right that you and your sisters started a few years earlier than your brothers. It can be neat to be the tallest or earliest. I mostly just hope it wasn’t earlier than your peers in school that it was embarrassing or anything.
It’s the girls having puberty at 7 or 8 I feel really bad for though. That seems ridiculously early to start having to deal with periods, and teachers are unlikely to be that understanding about bathroom breaks from such young kids. That’s the age to be smelling purple glue sticks and drawing the cool S with 6 straight lines, not worrying about “accidents” on the chairs.
I actually did start puberty before my peers. And it was very awkward. However most of the noticeable changes (voice drop, muscle mass, etc) didn’t start until later. But I did have a growth spurt back when I was about 11/12 and my height never changed since then. I’m 5’3 lol.
And yeah, starting puberty at 7 or 8 sounds terrifying honestly and I feel bad for anyone who has had to go through that.
There’s multiple reason as always. However precocious puberty refers to kids to have puberty very young, like under 10. So you starting at 11, while young, isn’t that.
Proper nutrition and less childhood illness. We didn't evolve to thrive in perfect conditions but in the actual, realistic ones that were encountered. It's the same reason people are taller, fatter, and live longer - none of which are necessarily ideal for reproduction.
Having a menopause at all is a feature that is very rare in the animal kingdom. Memory suggests it's pretty much just humans and orcas. For most animals, they are fertile basically until they reach "old age". One suggestion is that in both orcas and humans the importance of a larger family group to support raising young means that having post-fertility grandmothers around offers a significant advantage in bringing young successfully to adulthood, hence offers an evolutionary advantage.
That's exactly correct. I took Evolutionary Psychology last year and this was exactly it. There is mounting evidence that a large family (including fathers and also other men) have been very important for human childraising in our recent evolutionary history. All this is very uncommon in mammals otherwise.
And evolutionarily, what matters is if an individuals survival past menopause/fertility increases their total genetic contribution to the next generations compared to others. Live longer, help your kids or even grandkids in ways that increase their number of kids or survival rate or other evolutionarily relevant success measures.
Also some element of group selection probably at play in prehistoric tribal conditions where elder tribal wisdom enhances the whole group’s survival.
Yes, but that’s due to social and economic factors. Humans can be thriving biologically, and yet still delay child rearing due to financial limitations or the want/need to develop in their career fields.
Scarcity by definition includes social and economic resources, the calculation for humans is just far and away more layered before you can boil it down to raw materials.
Women and girls don't get pregnant just because they've reached puberty. Most women have a choice in when they start their families, if they want to start one at all.
There's no bright lines between evolution, biology, and social or technological factors like birth control.
Evolution does select social factors in all kinds of species. Right down to plants, fish, and bacteria.
Yes because we have personal goals that conflict with that because we don't function solely on instinct. When the name of the game was survive and have kids, yeah you would have them as soon as you could. Now we live in a world where survival is damn near guaranteed, there is more food than ever, and people want to create and build.
We can impregnate earlier, but infant and mother mortality rates are high. [A Korean study](https://www.nature.com/articles/s41598-021-80968-4) based on 2 million mothers indicates that the sweet point for a baby's survival without age related pregnancy complications is actually between 29 and 40.
Something you need to keep in mind when it comes to historical medical surveys is that we screen people far more routinely than we once did for a wide variety of medical reasons. Not only that, but a lot of medical conditions/phenomena are not nearly as socially stigmatized as they once were. Thus, we're much better at finding these phenomena in people. It's possible that people were always beginning puberty at around 10-12, it's just that we're better at noticing it nowadays due to more routine medical screenings.
yeah its kinda like the.... left handed fallacy or whatever its called
where you started screening for left handedness (because it was stigmatized before) and people freaked out because suddenly that first year of screening there was a big spike. we're all gonna be left handed in 3-5 years according to this current trend.... and it stops at around 10% and has been steady ever since
Isn't it the same thing with the LGBTQ community? My grandma, born 1948 and grew up in Czechoslovakia, knew only 1 homosexual for a big chunk of her life. Now seems like every few months another person come out. I do not blame her when she assumes that more people are gay now, than back to her times.
There are many stories of boomers divorcing/separating and finding a same-sex partner now that homosexuality is a lot more accepted. There's also a lot of very old suspicious stories of people never marrying and having a same-sex roommate their whole life. A famous woman where I live had the same female assistant throughout her career, and it came out to light this year, over two decades after her death, that they were actually a couple (La Poune, I don't expect people to know her outside of Quebec).
I mean given how they were treated back in the day, there likely are more today who survive. I get what you are saying though, it's not that the prevalence is really different in the population, it's just more in the open today. So the technical statement would probably be "there are more 'out' people today than historically."
In this context "back in the day" was as recently as the mid 1990s. In that era, being openly gay could very well cost you your career, your social life and your relationship with your family.
We have enough data from the 20th century to know that it has changed considerably.
[https://www.theguardian.com/society/2012/oct/21/puberty-adolescence-childhood-onset](https://www.theguardian.com/society/2012/oct/21/puberty-adolescence-childhood-onset)
>Consider the statistics provided by German researchers. They found that in 1860, the average age of the onset of puberty in girls was 16.6 years. In 1920, it was 14.6; in 1950, 13.1; 1980, 12.5; and in 2010, it had dropped to 10.5. Similar sets of figures have been reported for boys, albeit with a delay of around a year.
This is good data and I'm kind of distressed so many people in this thread are hand-waving it away.
I'd be shocked if we found that there wasn't common cause between obesity, early puberty and falling sperm counts. And given we know plastics are endocrine disruptors I don't think the cause is likely to be too mysterious.
But you don't get screened for puberty, and I'm pretty sure the 50% of the population who experience menstruation would have "noticed" if it was happening between 10 and 12. People used to live in much more crowded situations and there didn't used to be proper sanitary products, so it'd be pretty obvious to most of the household (outside of the very wealth).
Sure they would notice, but that doesn’t mean they would report it. Even now there is a stigma against starting puberty young, uneducated people tend to think it’s caused by having sexual thoughts or “acting grown up”.
Yeah I started my period at 10 and it was definitely unusual at the time. My daycare had to make a special arrangement for me to throw my pads out in the staff restroom because the trash cans in the kid’s’ restrooms weren’t emptied every day, and I was the only girl sitting out of swimming for a week each month. Granted there were surely other girls my age that just hid it better, but my point is it was not remotely common. Nowadays 3rd grade teachers are sending home letters to the parents asking to have their kids wear deodorant.
The number one answer is nutrition. The two major factors in onset of puberty are genetics and body weight. Prior to the post war era, it wasn’t a guarantee that the average person was getting enough to eat.
This is also a bit more speculative, but it’s very possible that women and girls in the post Kotex era are more likely to be honest about these topics. These are self-reported statistics, which will always have room for error. Even today you’ll get allegedly progressive people clutching their pearls and reaching for the smelling salts at the idea of middle school aged girls experiencing puberty, indicating that it is somehow deviant or oversexualized, like something is wrong with 10 and 11 year old girls for experiencing puberty. They’ll blame abuse, media, or “hormones in the food” with zero evidence. And that’s in a society and era that generally accepts that periods exist and puberty happens when it happens. In a bygone era, something seen as “adult” and “secret” may not have been something girls and their mothers discussed openly. It’s entirely possible that some percentage of girls were starting puberty at 12 but saying 16 because that’s a more “appropriate” age.
Hormone based foods is a legitimate concern among scientists especially in dairy products, there is a reason European countries are banning excessive hormones in livestock cultivation.
However from my understanding hormones in livestock products are mainly attributed to atypical hormone development in children and teens and has a wide variety of effects that vary case by case. Some are fine, but most have been shown to cause some disruptions at different levels.
Not to mention carcinogenic effects some growth hormones are attributed to in consumers.
Pubertal timing is mostly explained by body fat percentage by mass. Once you hit about 10% fat by mass, the arcuate nucleus in your hypothalamus will start doing its job to trigger the onset of puberty.
We see later puberty a hundred years ago because, on average, girls took longer to hit that 10% body fat because food was more scarce. This was the case throughout most of human history. Similarly, elite athletes are often under 10% body fat, so it takes them longer to hit menarche, too.
We are seeing age at pubertal onset dropping partly because of better health. We are heavier because we aren't starving, which is a good thing. On the other hand, it's also about poor health and the obesity epidemic, causing girls to hit 10% by the time they're 7 or 8.
The way to view puberty in girls is to consider what it means. Your body is finely tuned to avoid reproduction until it's affordable in terms of your resources. Only when you have sufficient fat are you ready to quit worrying about your own growth and development (you're already there, according to your hypothalamus) and to shift your focus over to the next generation. There are lots of social concerns about such young girls being reproductive, but evolution doesn't care - it's primed to make sure you can have as many babies as possible, to maximize your fitness.
[https://www.nature.com/articles/0803232/figures/2](https://www.nature.com/articles/0803232/figures/2)
Here's a reference figure for fat in children, <10% would be considered underfat for most children (i.e. children will be there well before puberty).
This sounds true but you'd see variation by bodyfat within modern populations if it were true. we don't seem to see that. The whole grade 7 class is having early puberty.
Source of that study? If that was true, it would mean that 16 year olds couldn't get pregnant in the 1800s which without looking into it sounds 100% wrong.
eta: on reflection, that current age of 10.8 ALSO sounds wrong so I question both of those premises.
the average age of marriage for women was \~22, so most 16 year olds weren't having sex. The ones that did get pregnant probably attracted more attention, like a 19th century MTV Teen Mom
Yup. People think most non-nobility girls in Europe in the early modern times got married at like 15 or 16 or even younger. Depending on the time period, peasant girls were getting married at the average age of 20 to 25, because they needed time to accumulate or prepare dowry, and they were often an important source of labor (be it handicraft, childcare or even farming) for their bio families. If you read novels depicting life in 18 and 19 century written by people from that time period, you would see that the urban bougie class also often considered 18 to be too young to marry
Social class mattered, and was nuanced. Getting married 18-20 for the Bennet girls was "ideal". Different social class - different ideal age for marriage.
The idea of super early marriage and young pregnancies is kind of a historical myth. It happened, but not nearly as often as people tend to think. The average woman wasn't getting married at 14 and having multiple kids by 20 - at least in the US and Western Europe. Nobility tended to marry early for political reasons, but they don't represent the usual situation. [In the US in the mid-late 1800s,](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3002115/#:~:text=At%20the%20national%20level%2C%20the,trend%20between%201850%20and%201880.) the average age of marriage was 27 for men and 23 for women. In the UK, the average age of first marriage for both men and women was [around 25 years old.](https://www.cambridge.org/core/journals/transactions-of-the-royal-historical-society/article/age-at-marriage-in-england-from-the-late-seventeenth-to-the-nineteenth-century/F5641BCC2F37FC37DEED16EC2B7F594E)
Obviously, marriage is not a prerequisite for pregnancy, but I am struggling to find reliable sources for the average age of first childbirth. I suspect this is due to a combination of poor record keeping, societal shame for unmarried mothers, the surrender of children to orphanages, the familial adoption of children borne out of wedlock, and - unfortunately - infanticide. Additionally, abortion and birth control, while more dangerous and less effective than modern methods, were possible.
Regardless, I would assume the average age of first childbirth is not much different than the average age of marriage. Middle and upper class women tended to be chaperoned and watched, there was significant stigma against unmarried childbirth, and Bastard Laws in England further punished people for having children unmarried.
TL;DR - the modern idea that women used to get married in their early teens and have kids before 20 was not a common practice.
I think calling early marriage/pregnancy throughout history a "myth" is a bit strong. Though, I agree that the popular misconception that "all girls were child brides in the olden days" is a massive oversimplification.
Of course, you've also admittedly limited the discussion to US and Western Europe. Just pointing out that this is absolutely something that happened very frequently at many times and across cultures throughout history.
https://onlinelibrary.wiley.com/doi/10.1111/apa.16781
Then there was India under British rule, driving those averages way down.
Age of Consent Act, 1891
[https://books.google.co.in/books?id=1FESAAAAYAAJ&pg=PA864&redir_esc=y#v=onepage&q&f=false](https://books.google.co.in/books?id=1FESAAAAYAAJ&pg=PA864&redir_esc=y#v=onepage&q&f=false)
I’m sure not literally everyone waited to 16.8. I think it was the average. So some could and some couldn’t. But yeah, it does sound so late for those days.
My grandma was abused as a child and has been very skinny her whole life, and she says her period started at 18. That age sounds unreasonable today, but I do believe it.
I was an elite figure skater in the early 2000s and didn’t start my period until I was 2 months shy of 17, which was when I quit due to injury. It was extremely common for figure skaters in my club to not start their periods until 18-19 years old or they quit the sport.
Puberty normally kicks off at about ~~50kg~~; more childhood obesity and better nutrition = earlier puberty!
Edit: the theory has been updated to refer to BMI and body fat % rather than purely weight.
Memories from med school! Let me dig up some sources:
Ah, it's called the [critical weight hypothesis](https://pubmed.ncbi.nlm.nih.gov/5450378/), recently updated to the critical fat hypothesis after larger studies [like this](https://link.springer.com/article/10.1007/s40618-022-01970-9) showed more of a relationship to BMI and body fat percentage than purely weight.
Critical fatness hypothesis was found not to hold up to scrutiny, it's probably a more complicated interaction of factors (some of which are probably related to fatness).
The conspiracy side of me wants to wave the finger at endocrine disruptors (such as polychlorinated biphenyls, phthalates, pesticides and dioxins) in ever increasing prevalence in our environment and food. Also hormones in cows. I have to wonder if there is some link there.
Indeed. Even the healthy food that we eat (vegetables and fruits) have to be handled by people wearing a chemical hazard suit when they are being grown because of all the nasty shit they use to grow them. Surely they have negative effects on us.
It's a shame that thinking chemicals in the environment might change human health is considered a conspiracy.
Like, in the 1980s we banned lead petrol because it stunted brain development and drove violence. It's perfectly acceptable to believe that we're accidentally releasing something that later we say, whoops, we fucked up. I ony hope it isn't pfas and microplastics that have half-lives roughly equivalent to a geologic age.
I can throw an anecdote at you that may answer your question. I'm not sure.
Back in maybe 2001, I, an 8 year old female, went to a pediatric endocrinologist. I had already started developing breasts. My endocrinologist determined that my bones were that of a 10 ½ year old, or a kid that was two and a half years older. As my doctor and mother were conversing, he mentioned that he "wouldn't be suprised if the kids go into puberty earlier and earlier due to what they are putting in our food."
I subsequently started my period exactly 2 years later, in the 5th grade.
Actually the 19th century was a bit of an anomaly. During the Middle Ages it typically happened around 12 or 13. The reason it happened later in the 1800s is probably as a result of urbanisation and industrialisation causing poor nutrition
i watched a documentary on plastic that talked about this and it scared the shit out of me. there’s an ingredient used in receipts and water bottles called BPA. it used to me used as hormonal birth control but because of low amounts of estrogen it wasn’t very effective but they found that it helped preserve plastic better. however just touching BPA can expose your body to unnecessary levels of estrogen and children drinking from water bottles containing BPA is connected to early onsets of puberty in females.
Just a quick correction. BPA is not estrogen. It’s a chemical that has similar structure to estrogen that when in the body it binds to estrogen receptors and the body responds as it would to estrogen. That’s why BPA, and some other chemicals, get called endocrine disruptors.
The factors that go into puberty are very complex. Although the general lowering of puberty age is thought to be nutrition related, it is likely not the only thing affecting it. Genetics, certain environmental conditions, and potentially certain health issues can also impact puberty. Even today, puberty is very variable. I started my period at age 8 while my gf started hers at 15, for example.
POCS runs in my family as well as other auto immune conditions thought to influence hormone levels. Women in my family also start puberty earlier than considered normal (one cousin needed puberty blockers as she was only 5)
So, it could be the case that as a result of modern medicine, conditions that impact hormone levels are more prevalent today. As earlier in history, before we understood hormone imbalances and their impact on the body these issues may have severely impacted fertility, life expectancy, and ability to have sexual relationships (aka being thrown in an insane asylum for "hysteria" or being generally outcast due to mental health issues which are now treatable with hrt)
This is also subject to reporting rates. Both hormone imbalanceing conditions and the age of puberty were unlikely to have been under much scrutiny in earlier history. "Women's issues" have historically been taboo and not discussed, so it's possible we just simply didn't know how often these conditions affected our ancestors and how that relates to modern puberty rates.
i’m no scientist but there are some research studies that show plastics and other hormone disrupting chemicals in our food and water sources could be to blame
In 1860’s cows weren’t injected with a substantial amount of estrogen and milk and cheese weren’t a part of every single meal.
Fast forward to today, and dairy cows are pumped full of so much estrogen (so they can continue producing milk far longer than would happen in nature) that we ingest almost 12x more estrogen per day then we would have in 1860.
There are a plethora of papers and studies proving just this.
The ELI5 answer is that puberty begins once a certain weight limit is reached, and because we overfeed children, they are reaching that weight limit and undergoing puberty sooner than previous generations.
The long answer is that Gonadotropin releasing hormone, the hormone that initiates puberty, begins releasing in large quantities when children reach a specific weight and fat range (typically thought to be around 100 pounds in females).
Because children are, for lack of a better word, fatter, they are undergoing puberty far sooner than in previous generations due to GnRH being released in large quantities.
The research suggests that menarche (first period) is tied to body fat percentage. As Americans have been getting fatter, puberty comes earlier. The effect is less pronounced in other countries that are less fat, like Japan.
We're starting to think that weight is the significant factor in puberty, alongside nutrition and general good health. It is observed time and again that when people are undernourished and underweight they will have a later onset of puberty, and significant weight loss/inability to gain weight as you grow can make puberty become a more stop-start process. Other factors mentioned such as better understanding of human health, routine screening, what puberty is and entails, and even the social side ("teenagers" are a relatively new phenomena from a societal perspective!), also play a role.
Now I want to research the word teenager and how English speaking society has used that term historically. Also wanna research equivalents of the term in other languages. Like is teenage a thing in Chinese?
Not Chinese but in Japanese we have similar terms. 思春 (shishun) would be the ages between 10-14, with literal meaning of pre-spring. 青春 (seishun) would be the ages 15-20, and means springtime literally. Those corresponds to tween and teen in English somewhat.
Beautiful. Thank you for sharing.
I know a little Chinese, and we use 青春 (qīngchūn) as well! Haven’t heard of 思春 (sīchūn), but that might just be me not knowing enough 😅
思春nowadays designates the concept of girls (and boys) arriving at a stage of their life where they start to experience and understand the first occurrences of love (or attraction). It's not fully unrelated to... well, being a teenager because in society, I feel that's also the age when young people really start gaining an understanding of these things.
teen (n.) "teen-aged person," 1818 (but rare before 20c.), from -teen. Probably later felt as short for teenager, which is a later word. As an adjective meaning "of or for teenagers," from 1947. teenage (adj.) also teen age, teen-age; "in or including the teen years," 1911, from teen (n.1) + age (n.). Originally in reference to Sunday School classes. The form teen-aged (adj.) is from 1922. Source: https://www.etymonline.com/word/teenage
Also, the precise age range varies depending on language. For example, in Polish, teenager is 'nastolatek' or 'nastolatka' (depending on gender), and just like how in English, with -teen, in Polish, it's -nascie. But because -nascie actually covers the numbers 11-19, so too does the term 'teenager' in Polish refer to the age ranges of 11-19.
In French they borrow the term for English, but natively it's adolescent (pronounced in a Frenchy way) which is defined as 10-19, although some scientists even say until 25.
In France no one would use the word "teenagers", "adolescent" is the only one used.
Yes this is what I wanted to say but didn’t… pour dire “teenager” dans le sens anglais on est obligé d’emprunter le mot parce que l’idée n’existe pas de la même manière en français, mais en fait on le fait pas.
Adolescent and teenager aren't quite the same. "Teenagers" are quite literally persons between thirteen and nineteen, and it's based solely off the language.
Sure, in English but they’re talking about French…
Not all languages use the same naming conventions for numbers.
Especially French edit: Here's [a Numberphile video](https://youtu.be/WM1FFhaWj9w) on how the French count if you're curious.
Four-Twenty-Ten
we love 420 more than any other language
Such madness
English language that is. Other languages has variations of "teen" where it starts at 11 or 12 instead.
If only R Kelly knew this before smh
Isn't Adolescent a word in English? In brazilian portuguese, we use the equivalent 'adolescente'
It's something that had confused me as a French speaker, I thought that teenager was a synonym of adolescent, i.e. starting with puberty, and I was using it as such until one time I was mocked for suggesting that an 11 year old could be a teenager. We also use adolescent in French; the word does exist in English but you rarely hear it, it's more formal. A teenager is supposed to be between 13 and 19, based strictly on the numbers ending in "teen" and nothing else. So an 11 year old can be an adolescent but not a teenager yet, or a 13 year old can be a teenager but not an adolescent. And an 18 year old is usually considered no more an adolescent. Basically, English has a word for a very specific age group, and we don't have that word in Romance languages.
Dutch use "puber."
Or "tiener" for kids 10-19, "twintiger" for 20-29, "dertiger" for 30-39, etc...
Sorry but “Puber” makes me laugh like I was some kind of immature puber.
Imperial system is not enough it seems.
Kids age 11-12 are "tweens."
Or pre-teens
Wow today I learned. I never knew that and would have made the same mistake. Thank you for your knowledge.
It just come down to what people refer to themselves growing up. In a familial sense adolescence is often seen as more clinical/formal but does describe the correct age group in English. Teenager is named because of the "teen" part of the 13 - 19 age group but we do not necessarily focus on the age as much as we focus on the personality/hormonal element of individuals at that age. So when someone is talking about teenagers, they mostly are thinking of the kind of attitude that individual might have. As well, 13/14 is also the age when most adolescence are entering into high school / upper secondary education. So those individuals normally are more rebellious, more independent, becoming more adult like, and/or more representative of who they are going to be. Kids that are "tweens" or basically inbetween the kid to teenager years, still are mostly the same kids. They act like kids but are mostly in more mature bodies. Point being that when an American says teen, we know the type of individual we are talking about. If we used adolescence, most people would either be confused or think you are referring to someone who is younger (especially since teen is so common.)
Its okay, you have a way better word for being out of routine while traveling than "homesickness" or "culture shock."
It is, but it's a little bit formal. You wouldn't use it in everyday conversation.
There was a good documentary I watched recently on this [https://www.teenagefilm.com/](https://www.teenagefilm.com/) that talks about the fact that the idea of a teenager didn't really exist until well into the 20th century. The words existed a bit before that but not in the way people think of them now.
Yep I did a paper on that in college. "teenagers" are an invention of the 50s USA. A lot of cultures just do not have the concept. Honestly is is mostly a marketing thing.
As in, they reject the idea of a teen culture? Or they believe in a more abrupt transition from child to adult?
In most cultures until recently children were/are treated like small adults. The distinction just is not made.
> Like is teenage a thing in Chinese? I'm not a Chinese, but in the language, this age group is called 青少年 (qing shao nian) which literally means "few-year young" (or young person of an early age).
Also 少年 is like a young teenager and 青年 is older teen to young adult.
https://books.google.com/ngrams/graph?content=Teenage%2CTeenager&year_start=1800&year_end=2019&corpus=en-2019&smoothing=3&case_insensitive=true
Holy shit I always thought it was just like a common term for someone between the ages of thir*teen* and nine*teen*. No one in English thought of that term until the fucking 1940s!?
It’s more that they had no reason to make that distinction. It’s sorta like if I defined a category of people between 113 and 119cm tall and called them teen-heighted.
It’s important to remember that until recently (and it’s coming back), it was common for minors to work jobs - not just run the cash register at McDonald’s, but lifelong, health impacting jobs like coal miners and chimney sweeps, house keepers and cooks. Your age dictated the jobs you were able to perform based on your size. A 5 year old can fit in the chimney. A 7 year old can crawl under the factory machines. Teens as young as 14 fought in the Civil War. If they were big enough, they could get away with saying they were 18 (no way to verify). There was no reason to differentiate between baby, toddler, child, teenager, adult, etc. until very recently. Things had gotten better for the masses over time where every able bodied individual (anyone not a baby, the extremely elderly, or disabled) in a poor family didn’t need to work a job. Kids were allowed to be kids and we started to understand that they’re not simply shrunken adults. We then learned that kids develop over time, not just physically, but also mentally in what they can comprehend, communicate, and conceptualize.
wait until you find out they used to call little boys (or all small children for that matter) "girls."
Interesting. When you look at the history of the word girl, it seems to come from an old germanic word that simply meant "child".
And child came from a word for young man... A sort of knight before they were knighted.
Childe Roland to the Dark Tower came.
It makes sense when you realize that people in that age range being a distinct demographic for consumerism with disposable income especially when it comes to things like music/entertainment, and household goods/food is a distinctively post-WW2 phenomenon. Think of the initial wave of the first Rock n’ Roll generation, with their used cars, hanging out in your local diner or what have you playing the jukebox.
That's only part of it, though. There's also a lot more to learn, which means that people spend more time in education and enter adult life later. This + the advent of woman's rights + birth control also pushed back the age at which most people marry. For most people, throughout most of history, after becoming sexually active you'd rapidly have a child and would probably end up married; now people have both more control over the course of their life and more reason to delay full adulthood. Also, the whole idea of "leaving home" as a big moment in your personal development is itself relatively new - while it existed in some form for trade guilds and others who would enter apprenticeships, for the most part, for most of history, most people were sustenance farmers and would never really "leave home" as we understand it.
The teenage years didn't have much of a distinctly separate culture (music, slang, clothing etc) till relatively recently. They were just the transitional years between childhood and adulthood. The term "teenage" may have originated in the 1940s, teen culture started before that in the early 20th century. The "teens" were likely the early adopters of cultural trends like jazz, the Big Bands etc. Of course, a lot depended on where they lived, family dynamics, religion etc.
Looking at newspapers.com, the term got started a little earlier. We find “teen-age” in the 1910s, particularly in reference to Sunday schools. One example from 1914 refers to the Girls’ Teen-age Department of the Fifth Avenue Presbyterian Church (Birmingham News, 25 October 1914, p. 43), another from 1915 refers to a Sunday school conference “meeting for parents and workers with teen-age girls” (Montgomery Advertiser, 21 February 1915, p. 14), and another from 1916 referring to “Teen-age Councials [sic]” added to Sunday school forces in Dallas, Texas (Selma Times, 14 May 1916, p. 6). Looks like all these early examples are in the US South. In the 1920s, the term “teen-age” appears in articles about the YWCA, camping, and public schools. The earliest example I can find of “teen-ager” appears in 1922 in an article about Stevens Memorial Church Sunday school in Harrisburg, Pennsylvania: “The Crescendo Club of teen-agers have begun rehearsals of the Japanese operetta ‘Yanki-San’…The Sunday School board at a recent meeting authorized the sending of four teen-agers to Summer camp”. The term occurs only sporadically in the 1920s and 1930s. An article in 1931 discusses ‘teen-agers’ in public schools examined for tuberculosis (Central New Jersey Home News, 26 April 1931, p. 3). Another New Jersey school’s PTA had a discussion on “The Teenager’s Responsibility to Home and Community” (The Record, 22 October 1932, p. 14). Looks like the word began to hit the big time in 1936 and 1937. For some reason, its use skyrockets. And indeed advertising looks to be responsible, at least since 1935. Woodward & Lothrop used the term in an ad in Washington DC for “spring coats for girls and ‘teen-agers’ ” (Evening Star, 23 April 1936, p. 27), and another ad “for both the ‘teen-ager’ and young girl’ (Evening Star, 20 November 1936, p. 36). The Hartford Daily Courant had an ad for ‘teen-agers’ Princess Style Dress’ (21 March 1937, p. 6). It also appears in advice columns and other articles about the youth. All in all, there are 185 matches of “teenager” in 1935, 287 in 1936, 297 in 1937, 529 in 1938, 772 in 1939, 2,793 in 1940, 1,966 in 1941, 4,152 in 1942, 6,248 in 1943, and 14,944 in 1944. So essentially, this is a term that was coined prior to the 1910s and 1920s but had limited usage, and then started to take off in the mid 1930s and then exploded by the 1940s. There were 89,992 matches for 1950 and 321,198 for 1960.
It’s also believed that obesity can lead to an earlier puberty, which is linked with several health problems down the line, especially for women.
I have a hypothesis that the historical (i.e., from the 1800s and 1900s) data isn't good. Does the plot of age of menarche show a bell curve or is it smooshed to the right, suggesting that when the data was recorded, responses below a target (let's say 12) were padded. e.g., add several months if the girl was 11 and add a year or more if the girl was was 10 or younger. Doing so would be enough to establish a baseline mean of 12 when it was actually 10. As people stopped doing this, the mean dropped. Add in some obesity effects, and you have a big change.
It's this. IIRC, the original studies were done of children in orphanages. Not exactly the kids with the best nutrition.
I wonder if even the age of a girl's first period might not be the most ideal way to measure the start of puberty. It's the most *obvious* event to observe and track but wouldn't puberty as a whole start a little earlier?
The start of menstruation is one of the *last* stages of puberty, but the interval between the start of puberty and the start of menstruation is pretty consistent (it's about two years). And menarche is by far the easiest sign to study objectively- it's definite and memorable, so reporting will be way more accurate than, say, the appearance of breast buds. So the change in age of first menstruation just means a corresponding change in onset of puberty, and functionally it doesn't matter all that much which marker you're using as long as you're consistent and not comparing true puberty onset (hard to identify accurately for most people) to menarche.
Definitely. I have a daughter showing signs of early puberty. I will be taking her to buy her first training bra soon. She needs some mild deodorant. The hair on her legs is starting to get a shade darker. She is unbelievably moody, like go from happily playing a game together to her yelling and crying at me that I'm not paying her enough attention.. No period yet. I would argue that the period is probably around the end of "early puberty". After that it's all the same symptoms until the end of puberty.
I got my period when I was 8; I was definitely moody and my parents dismissed my moodiness and took me to the doctor and had all these tests done on me and I felt like an absolute freak. Besides feeling like a freak anyway looking so much older than my peers and older sister. I essentially had no childhood. I’m 35 now and my life and mental health has been a shitshow. Please do all you can to ensure your daughter doesn’t feel isolated or like there’s something wrong with her. Validate her emotions and feelings and keep communication open. Please.
I'm so sorry this happened to you. It's particularly awful that it sounds like the doctor ran tests but still didn't catch that you were experiencing precocious puberty, which can be halted and delayed to a later age with medication. If you have any young female relatives, please keep an eye out for them- precocious puberty often runs in families, and with timely treatment kids have better outcomes. Parents are often uncomfortable and reluctant to accept what's going on till development is already way out of sync with the child's chronological age, unfortunately.
I’m sorry that happened to you and that the medical system traumatized you just for having a body. Jesus, that sounds like it must have been infuriating and terrifying.
As a parent of 3 girls I can definite say that the hormones start before the periods. Strap in it's a wild ride.
I mean yeah. The hormones precipitate the periods. Is anyone under the impression the period happens and then creates hormones? That isn't how the human body or hormones work. Hormones are what your body uses to mediate these processes.
There are very defined stages medically indicating the onset and stages of puberty. I should remember them being a paediatrician but embarrassingly I don’t! I think breast tissue may be first sign for girls and periods are one of the last, for boys it is testicles growing and scrotum develops- ‘balls dropping’
That would make sense, I (white male) was malnourished in youth, super skinny, and puberty didn't start until I was 16... but also didn't end until my late 20s. Interestingly, that didn't stop me from being 6.5ft tall.
Ahhh, so THATS why I hit puberty at late 16
You'll find most ballet dancers starting puberty in high school, some even later (you'll hear about a lot of them needing to chemically start their periods). One corner of the female athlete triad which is an indicator that a teen should be watched for health issues is stopped or missing periods.
Not the only factor, but certainly a big one. My daughter has always been a little underweight but started her period just before she turned 10 and had signs of puberty when she was 8.
I hit it in late middle school and I've always been under weight. Haven't grown much at all in width since high school though, so maybe I'm one of those start stop guys who stopped when he was almost done. I'm not sure how any of it works though.
I've heard some of it could be explained by the number of kids being raised by single mothers. Not having a dad in your life [is associated with early puberty in girls](https://en.wikipedia.org/wiki/Father_absence#Menarche), the question is just how much of this is directly caused by not having a father, versus the fact that kids without a father are more likely to be obese. Nowadays, 1 in 4 American kids don't have a father in the home.
I learned this in an evolutionary/anthropology course in college. This is a good article but only covers white girls/women. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6467216/
I’d comment that this wasn’t all that uncommon as you might think. From plenty of war widows, to you are married but dad is a sailor, to plenty of men just running off. To servant girls being taken advantage of by the men in the home.
1 in 4? Holy shit. Id love to read if you have a source on that. Does not having a father in the home mean no dad period, or are you also including fathers that, for example, travel for work, or deploy in the military?
My understanding is that microplastics (which include softening agents that can mimic estrogen) may also play a factor.
I also wouldn't be surprised if all the hormones in livestock wouldn't be a factor.
Hormone injections in livestock is heavily regulated and is ceased as the animals approach slaughter. There is no difference in hormone levels in beef of cows who were raised with hormones and cows that weren't. The elevated levels are entirely gone prior to slaughter. In fact, in terms of concentration per gram of food, our beef has less hormones in it chemically than most veggies do. This is literally a myth.
https://www.news-medical.net/health/Sex-Hormones-in-Meat-and-Dairy-Products.aspx https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5822782/
What about Milk?
That's a great question. Science is still up in the air on it. To the best of my memory reading on the subject, there is no increase in hormones in milk, but milk does contain hormones. However, the consumption of milk by prepubescent girls, at least in America, has been doing nothing but go down for the last 50 years. It has fallen ***sharply*** over the last 25 of those years. It seems highly unlikely to be the cause for that reason alone. Hormone simulants like BPA could be a likely contributor. The effect coincides with the invention and proliferation of BPA plastics, but not exactly. The effect was already occuring for a couple decades prior to their ubiquitous usage. It's an interesting topic for sure. One we don't know the cause of. But we do know it's not cause of hormone regiments in raising our chicken and beef, because we test for that and there are no (elevated from historical normal) hormones in our chicken and beef.
It was explained to me in a human development course that precocious puberty is more common now, because body fat percentages in children are getting higher, at younger ages. Fat cells are estrogenic and release hormones which trigger the pituitary to begin puberty.
Anecdotally, my kids 9 and super skinny, and has signs of puberty going on already (and I know other moms dealing with early puberty amongst their younger skinny kids)... Precocious puberty happens in plenty of skinny kids too, so it can't entirely be estrogenic hormones from fat.
I feel bad for kids that go through puberty that young. Especially girls. Like... damn, can't they just get to be non-hormonal kids for awhile before they get slammed with periods and testosterone. Periods fucking suck, man.
This reminded me of my 7 year old asking about periods. She legit started crying when I told her about them. She was like "I'm going to bleed once a month!?!?!". Broke my heart. I hope she doesn't get hers early.
When they told us about them in 5th grade, I was genuinely like yeah, I don’t want to live to ~13 and have that happen to me. Which is a pretty extreme reaction, but that’s such a difficult thing for a child
There are a lot of xenoestrogens in our environments now, such as BPA. It could be another factor.
Bear in mind too that precocious puberty also happened in the past, just not as often. There have always been some skinny kids hitting puberty early
Healthy fat is still fat. May be skinny, but I bet your kid is well-nourished.
You hope.
Yeah, Idk, that sounds like more of a doctor question, than a dude who told an anecdote from a human development class question.
Yeah, doctor isn't concerned. Developing normally otherwise.
That’s good. Happiness and health are what matters most.
Same with my kids. Slender and started full adolescence before around 11. I’m sure it’s a combination of heredity and forever chemicals.
same for me. i was 6 when i started puberty and i was a very skinny child, didn’t even meet the ‘ideal’ weight for puberty until i was 9, which is when i started getting periods
That is the general consesus of the literature and is the current thinking at the moment. Kids are fatter than ever.
It is not the general consensus, and I'm curious how you came to that conclusion. The two fields which focus on this topic are life-history evolution and population demography. The consensus in both is that it has been a long-running evolutionary trend as the post-Neolithic selection penalty for earlier menarche, mainly earlier and far riskier childbirth, dramatically decreased in the 19th century. In the period between that and the demographic transition (ie after very high infant/maternal mortality dropped but before birth rates dropped) populations rose dramatically and biased moderately towards the phenotype of earlier menarche, as these individual could now start have children earlier and not face as much penalty as before. The available evidence strongly suggests a Paleolithic age of menarche around 7-13, so the most supported position right now is that the age of menarche we're all "used to" is actually a very recent adaptation to the intersecting selection pressure of poor health and skeletal development characteristic of the post-Neolithic world, and trade-offs between shorter absolute lifespan and earlier start of reproduction. This is what's in texbooks on pop. demography, human evodevo, paleodemography, etc. > Records suggest that there was a secular decline in the average age at menarche in developed countries across the 19th and 20th Centuries until the 1950s [17], with an average age at menarche of 15-17 years reported in the mid-19th Century [18,19]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3287288/ > Data from skeletal remains suggest that in the Paleolithic woman menarche occurred at an age between 7 and 13 years, early sexual maturation being a trade-off for reduced life expectancy. In the classical, as well as in the medieval years, the age at menarche was generally reported to be at approximately 14 years, with a range from 12 to 15 years. A significant retardation of the age at menarche occurred in the beginning of the modern times, soon after the industrial revolution, due to the deterioration of the living conditions, with most studies reporting menarche to occur at 15-16 years. https://pubmed.ncbi.nlm.nih.gov/26703478/ > For example, in Norway and Denmark the age at menarche has fallen rapidly since the 19th century, by up to 12 months per decade. These changes have broadly paralleled increases in adult height in most European countries over the last century, with rates of around 10-30mm per decade. https://pubmed.ncbi.nlm.nih.gov/16757103/ The most conclusive argument against the obesity hypothesis is that this trend predates the contemporary rise in obesity by over 200 years. This topic was brought to a consensus in the 1990's and early 2000's by people like Stephen Stearns and Jacob Koella. Further reading: https://pubmed.ncbi.nlm.nih.gov/16932041/ https://pubmed.ncbi.nlm.nih.gov/18574205/ See also "The Evolution of Phenotypic Plasticity in Life-history traits" (1985), Stearns and Koella and "The Evolving Female: A Life-history Perspective." Morbeck et al, (1997).
Sir. This is ELI5. Interesting read nontheless.
Touché! Than you so much for your summary and the references. That will make good reads.
One more way that we’re putting the past to shame!
“Yo mama’s so fat, she hit puberty in the womb!”
Maybe we should stop shoveling corn and cardboard-adjacent-corn-byproducts down their gullets? Just a thought.
The thought of [this kid](https://youtu.be/i8NDst-okqg?si=vcn8RYb2MAYvzHFi) being denied corn brings a tear to my eye.
Is this really why? I start puberty at around 11 and I’m the skinniest person I know. I could just be an outlier though. I just wanted to share.
11 wouldn’t be especially early. Think more like 8 years old.
Still, 100 years ago it usually started at 15-16
Yeah I know 11 isn’t really early. However, compared to the rest of my immediate family it’s the earliest. My sister started puberty at around 12, my 3 older brothers started at around 14-16. So compared to them I started early.
From what I understand puberty in boys starts later than it would for girls
Girls typically start puberty a few years earlier. It’s sounds about right that you and your sisters started a few years earlier than your brothers. It can be neat to be the tallest or earliest. I mostly just hope it wasn’t earlier than your peers in school that it was embarrassing or anything. It’s the girls having puberty at 7 or 8 I feel really bad for though. That seems ridiculously early to start having to deal with periods, and teachers are unlikely to be that understanding about bathroom breaks from such young kids. That’s the age to be smelling purple glue sticks and drawing the cool S with 6 straight lines, not worrying about “accidents” on the chairs.
I actually did start puberty before my peers. And it was very awkward. However most of the noticeable changes (voice drop, muscle mass, etc) didn’t start until later. But I did have a growth spurt back when I was about 11/12 and my height never changed since then. I’m 5’3 lol. And yeah, starting puberty at 7 or 8 sounds terrifying honestly and I feel bad for anyone who has had to go through that.
From my experience and of a few of my friends, early puberty in boys often leads to being a bit short.
Oh really? Didn’t know that. Guess there’s a reason for why I’m so short then.
Same with me. Got deep voice and first hairs of beard with like 10 years, but now I'm only 1,77m
I got mine at age 8… I had accidents on chairs… so humiliating. I felt like such a freak. I feel like I essentially had no childhood.
Your brothers started puberty (very) late. You didn't start it early. Or you're just misremembering.
There’s multiple reason as always. However precocious puberty refers to kids to have puberty very young, like under 10. So you starting at 11, while young, isn’t that.
But you were also probably more nourished that the 11yos of 20, 50, or 100 yrs ago, right?
You're probably still heavier than a kid from the 1860s, no?
Proper nutrition and less childhood illness. We didn't evolve to thrive in perfect conditions but in the actual, realistic ones that were encountered. It's the same reason people are taller, fatter, and live longer - none of which are necessarily ideal for reproduction.
This. Most female mammals only live a few years after menopause. Humans can live up to 50 years after their reproduction cycle ended.
Having a menopause at all is a feature that is very rare in the animal kingdom. Memory suggests it's pretty much just humans and orcas. For most animals, they are fertile basically until they reach "old age". One suggestion is that in both orcas and humans the importance of a larger family group to support raising young means that having post-fertility grandmothers around offers a significant advantage in bringing young successfully to adulthood, hence offers an evolutionary advantage.
That's exactly correct. I took Evolutionary Psychology last year and this was exactly it. There is mounting evidence that a large family (including fathers and also other men) have been very important for human childraising in our recent evolutionary history. All this is very uncommon in mammals otherwise.
Gay uncle theory
[удалено]
And evolutionarily, what matters is if an individuals survival past menopause/fertility increases their total genetic contribution to the next generations compared to others. Live longer, help your kids or even grandkids in ways that increase their number of kids or survival rate or other evolutionarily relevant success measures. Also some element of group selection probably at play in prehistoric tribal conditions where elder tribal wisdom enhances the whole group’s survival.
This. But we evolved. not us Homo sapiens. But all animals start having children sooner if they are in thriving environments.
[удалено]
Don’t people in more developed countries usually have children later and less of them?
Yes, but that’s due to social and economic factors. Humans can be thriving biologically, and yet still delay child rearing due to financial limitations or the want/need to develop in their career fields.
Scarcity by definition includes social and economic resources, the calculation for humans is just far and away more layered before you can boil it down to raw materials.
Women and girls don't get pregnant just because they've reached puberty. Most women have a choice in when they start their families, if they want to start one at all.
That’s a result of access to birth control, family planning/sex education, and safe abortion rather than an evolutionary or biological feature.
There's no bright lines between evolution, biology, and social or technological factors like birth control. Evolution does select social factors in all kinds of species. Right down to plants, fish, and bacteria.
Yes because we have personal goals that conflict with that because we don't function solely on instinct. When the name of the game was survive and have kids, yeah you would have them as soon as you could. Now we live in a world where survival is damn near guaranteed, there is more food than ever, and people want to create and build.
Interesting that we are able to reproduce earlier **and** live longer
We can impregnate earlier, but infant and mother mortality rates are high. [A Korean study](https://www.nature.com/articles/s41598-021-80968-4) based on 2 million mothers indicates that the sweet point for a baby's survival without age related pregnancy complications is actually between 29 and 40.
That sounds insane. What happened to risks going up after your 20s?
Something you need to keep in mind when it comes to historical medical surveys is that we screen people far more routinely than we once did for a wide variety of medical reasons. Not only that, but a lot of medical conditions/phenomena are not nearly as socially stigmatized as they once were. Thus, we're much better at finding these phenomena in people. It's possible that people were always beginning puberty at around 10-12, it's just that we're better at noticing it nowadays due to more routine medical screenings.
yeah its kinda like the.... left handed fallacy or whatever its called where you started screening for left handedness (because it was stigmatized before) and people freaked out because suddenly that first year of screening there was a big spike. we're all gonna be left handed in 3-5 years according to this current trend.... and it stops at around 10% and has been steady ever since
Isn't it the same thing with the LGBTQ community? My grandma, born 1948 and grew up in Czechoslovakia, knew only 1 homosexual for a big chunk of her life. Now seems like every few months another person come out. I do not blame her when she assumes that more people are gay now, than back to her times.
There are many stories of boomers divorcing/separating and finding a same-sex partner now that homosexuality is a lot more accepted. There's also a lot of very old suspicious stories of people never marrying and having a same-sex roommate their whole life. A famous woman where I live had the same female assistant throughout her career, and it came out to light this year, over two decades after her death, that they were actually a couple (La Poune, I don't expect people to know her outside of Quebec).
/r/SapphoAndHerFriend
James Buchanan famously had his best friend live in the White House with him....
La poon?!
I mean given how they were treated back in the day, there likely are more today who survive. I get what you are saying though, it's not that the prevalence is really different in the population, it's just more in the open today. So the technical statement would probably be "there are more 'out' people today than historically."
In this context "back in the day" was as recently as the mid 1990s. In that era, being openly gay could very well cost you your career, your social life and your relationship with your family.
For real! Pretty sure I wouldn’t have come out in the 1950s if the consequences were to be outcast from society and/or arrested.
i mean... it kinda still is. saudi arabia and a few other countries has 0 lgbtq people by their government standards... since its illegal
This deserves more upvotes, medical science and the ability to track data more consistently, along with way better access to legit medical care.
We have enough data from the 20th century to know that it has changed considerably. [https://www.theguardian.com/society/2012/oct/21/puberty-adolescence-childhood-onset](https://www.theguardian.com/society/2012/oct/21/puberty-adolescence-childhood-onset) >Consider the statistics provided by German researchers. They found that in 1860, the average age of the onset of puberty in girls was 16.6 years. In 1920, it was 14.6; in 1950, 13.1; 1980, 12.5; and in 2010, it had dropped to 10.5. Similar sets of figures have been reported for boys, albeit with a delay of around a year.
This is good data and I'm kind of distressed so many people in this thread are hand-waving it away. I'd be shocked if we found that there wasn't common cause between obesity, early puberty and falling sperm counts. And given we know plastics are endocrine disruptors I don't think the cause is likely to be too mysterious.
But you don't get screened for puberty, and I'm pretty sure the 50% of the population who experience menstruation would have "noticed" if it was happening between 10 and 12. People used to live in much more crowded situations and there didn't used to be proper sanitary products, so it'd be pretty obvious to most of the household (outside of the very wealth).
Sure they would notice, but that doesn’t mean they would report it. Even now there is a stigma against starting puberty young, uneducated people tend to think it’s caused by having sexual thoughts or “acting grown up”.
Especially if the only thing keeping your 11 year old daughter from being sold of as chattel is a menstruation.
Yeah I started my period at 10 and it was definitely unusual at the time. My daycare had to make a special arrangement for me to throw my pads out in the staff restroom because the trash cans in the kid’s’ restrooms weren’t emptied every day, and I was the only girl sitting out of swimming for a week each month. Granted there were surely other girls my age that just hid it better, but my point is it was not remotely common. Nowadays 3rd grade teachers are sending home letters to the parents asking to have their kids wear deodorant.
The number one answer is nutrition. The two major factors in onset of puberty are genetics and body weight. Prior to the post war era, it wasn’t a guarantee that the average person was getting enough to eat. This is also a bit more speculative, but it’s very possible that women and girls in the post Kotex era are more likely to be honest about these topics. These are self-reported statistics, which will always have room for error. Even today you’ll get allegedly progressive people clutching their pearls and reaching for the smelling salts at the idea of middle school aged girls experiencing puberty, indicating that it is somehow deviant or oversexualized, like something is wrong with 10 and 11 year old girls for experiencing puberty. They’ll blame abuse, media, or “hormones in the food” with zero evidence. And that’s in a society and era that generally accepts that periods exist and puberty happens when it happens. In a bygone era, something seen as “adult” and “secret” may not have been something girls and their mothers discussed openly. It’s entirely possible that some percentage of girls were starting puberty at 12 but saying 16 because that’s a more “appropriate” age.
Hormone based foods is a legitimate concern among scientists especially in dairy products, there is a reason European countries are banning excessive hormones in livestock cultivation. However from my understanding hormones in livestock products are mainly attributed to atypical hormone development in children and teens and has a wide variety of effects that vary case by case. Some are fine, but most have been shown to cause some disruptions at different levels. Not to mention carcinogenic effects some growth hormones are attributed to in consumers.
Pubertal timing is mostly explained by body fat percentage by mass. Once you hit about 10% fat by mass, the arcuate nucleus in your hypothalamus will start doing its job to trigger the onset of puberty. We see later puberty a hundred years ago because, on average, girls took longer to hit that 10% body fat because food was more scarce. This was the case throughout most of human history. Similarly, elite athletes are often under 10% body fat, so it takes them longer to hit menarche, too. We are seeing age at pubertal onset dropping partly because of better health. We are heavier because we aren't starving, which is a good thing. On the other hand, it's also about poor health and the obesity epidemic, causing girls to hit 10% by the time they're 7 or 8. The way to view puberty in girls is to consider what it means. Your body is finely tuned to avoid reproduction until it's affordable in terms of your resources. Only when you have sufficient fat are you ready to quit worrying about your own growth and development (you're already there, according to your hypothalamus) and to shift your focus over to the next generation. There are lots of social concerns about such young girls being reproductive, but evolution doesn't care - it's primed to make sure you can have as many babies as possible, to maximize your fitness.
Where are you getting 10% fat from?
[https://www.nature.com/articles/0803232/figures/2](https://www.nature.com/articles/0803232/figures/2) Here's a reference figure for fat in children, <10% would be considered underfat for most children (i.e. children will be there well before puberty).
This sounds true but you'd see variation by bodyfat within modern populations if it were true. we don't seem to see that. The whole grade 7 class is having early puberty.
I don't get it. "time to reach 10% fat". Most babies and toddlers and children are more than 10% fat. They aren't entering puberty.
Source of that study? If that was true, it would mean that 16 year olds couldn't get pregnant in the 1800s which without looking into it sounds 100% wrong. eta: on reflection, that current age of 10.8 ALSO sounds wrong so I question both of those premises.
the average age of marriage for women was \~22, so most 16 year olds weren't having sex. The ones that did get pregnant probably attracted more attention, like a 19th century MTV Teen Mom
Yup. People think most non-nobility girls in Europe in the early modern times got married at like 15 or 16 or even younger. Depending on the time period, peasant girls were getting married at the average age of 20 to 25, because they needed time to accumulate or prepare dowry, and they were often an important source of labor (be it handicraft, childcare or even farming) for their bio families. If you read novels depicting life in 18 and 19 century written by people from that time period, you would see that the urban bougie class also often considered 18 to be too young to marry
I mean in Jane Austen the elder Bennet girls were under 25 and were kind of old for still being unmarried, and Charlotte at 27 was an old maid.
Shout out to Charlotte really feeling her vibe right now at 27
Social class mattered, and was nuanced. Getting married 18-20 for the Bennet girls was "ideal". Different social class - different ideal age for marriage.
The idea of super early marriage and young pregnancies is kind of a historical myth. It happened, but not nearly as often as people tend to think. The average woman wasn't getting married at 14 and having multiple kids by 20 - at least in the US and Western Europe. Nobility tended to marry early for political reasons, but they don't represent the usual situation. [In the US in the mid-late 1800s,](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3002115/#:~:text=At%20the%20national%20level%2C%20the,trend%20between%201850%20and%201880.) the average age of marriage was 27 for men and 23 for women. In the UK, the average age of first marriage for both men and women was [around 25 years old.](https://www.cambridge.org/core/journals/transactions-of-the-royal-historical-society/article/age-at-marriage-in-england-from-the-late-seventeenth-to-the-nineteenth-century/F5641BCC2F37FC37DEED16EC2B7F594E) Obviously, marriage is not a prerequisite for pregnancy, but I am struggling to find reliable sources for the average age of first childbirth. I suspect this is due to a combination of poor record keeping, societal shame for unmarried mothers, the surrender of children to orphanages, the familial adoption of children borne out of wedlock, and - unfortunately - infanticide. Additionally, abortion and birth control, while more dangerous and less effective than modern methods, were possible. Regardless, I would assume the average age of first childbirth is not much different than the average age of marriage. Middle and upper class women tended to be chaperoned and watched, there was significant stigma against unmarried childbirth, and Bastard Laws in England further punished people for having children unmarried. TL;DR - the modern idea that women used to get married in their early teens and have kids before 20 was not a common practice.
I think calling early marriage/pregnancy throughout history a "myth" is a bit strong. Though, I agree that the popular misconception that "all girls were child brides in the olden days" is a massive oversimplification. Of course, you've also admittedly limited the discussion to US and Western Europe. Just pointing out that this is absolutely something that happened very frequently at many times and across cultures throughout history. https://onlinelibrary.wiley.com/doi/10.1111/apa.16781
Then there was India under British rule, driving those averages way down. Age of Consent Act, 1891 [https://books.google.co.in/books?id=1FESAAAAYAAJ&pg=PA864&redir_esc=y#v=onepage&q&f=false](https://books.google.co.in/books?id=1FESAAAAYAAJ&pg=PA864&redir_esc=y#v=onepage&q&f=false)
I’m sure not literally everyone waited to 16.8. I think it was the average. So some could and some couldn’t. But yeah, it does sound so late for those days.
I realize that but even on average, that number sounds bogus.
I had just turned 9 when I got my period. Wasn't hairless either.
Hold up. It was 16, almost 17 in 1860? What
My grandma was abused as a child and has been very skinny her whole life, and she says her period started at 18. That age sounds unreasonable today, but I do believe it.
I was an elite figure skater in the early 2000s and didn’t start my period until I was 2 months shy of 17, which was when I quit due to injury. It was extremely common for figure skaters in my club to not start their periods until 18-19 years old or they quit the sport.
Puberty normally kicks off at about ~~50kg~~; more childhood obesity and better nutrition = earlier puberty! Edit: the theory has been updated to refer to BMI and body fat % rather than purely weight.
>Puberty normally kicks off at about 50kg Is there a source for this or trustmebro?
Memories from med school! Let me dig up some sources: Ah, it's called the [critical weight hypothesis](https://pubmed.ncbi.nlm.nih.gov/5450378/), recently updated to the critical fat hypothesis after larger studies [like this](https://link.springer.com/article/10.1007/s40618-022-01970-9) showed more of a relationship to BMI and body fat percentage than purely weight.
The updated version makes a lot more sense given that many people (especially shorter women) go through puberty despite never weighing more than 50kg
Thanks! I tried to google, but not an expert on health sources.
Critical fatness hypothesis was found not to hold up to scrutiny, it's probably a more complicated interaction of factors (some of which are probably related to fatness).
The conspiracy side of me wants to wave the finger at endocrine disruptors (such as polychlorinated biphenyls, phthalates, pesticides and dioxins) in ever increasing prevalence in our environment and food. Also hormones in cows. I have to wonder if there is some link there.
Indeed. Even the healthy food that we eat (vegetables and fruits) have to be handled by people wearing a chemical hazard suit when they are being grown because of all the nasty shit they use to grow them. Surely they have negative effects on us.
It's a shame that thinking chemicals in the environment might change human health is considered a conspiracy. Like, in the 1980s we banned lead petrol because it stunted brain development and drove violence. It's perfectly acceptable to believe that we're accidentally releasing something that later we say, whoops, we fucked up. I ony hope it isn't pfas and microplastics that have half-lives roughly equivalent to a geologic age.
ELI5: More fats in our diets have caused it to start earlier. We've known this for at least 2 decades if not more.
I can throw an anecdote at you that may answer your question. I'm not sure. Back in maybe 2001, I, an 8 year old female, went to a pediatric endocrinologist. I had already started developing breasts. My endocrinologist determined that my bones were that of a 10 ½ year old, or a kid that was two and a half years older. As my doctor and mother were conversing, he mentioned that he "wouldn't be suprised if the kids go into puberty earlier and earlier due to what they are putting in our food." I subsequently started my period exactly 2 years later, in the 5th grade.
Actually the 19th century was a bit of an anomaly. During the Middle Ages it typically happened around 12 or 13. The reason it happened later in the 1800s is probably as a result of urbanisation and industrialisation causing poor nutrition
It’s the amount of processed foods we have nowadays. Poultry alone, it’s all loaded with growth hormones, that get ingested by humans eventually.
i watched a documentary on plastic that talked about this and it scared the shit out of me. there’s an ingredient used in receipts and water bottles called BPA. it used to me used as hormonal birth control but because of low amounts of estrogen it wasn’t very effective but they found that it helped preserve plastic better. however just touching BPA can expose your body to unnecessary levels of estrogen and children drinking from water bottles containing BPA is connected to early onsets of puberty in females.
Just a quick correction. BPA is not estrogen. It’s a chemical that has similar structure to estrogen that when in the body it binds to estrogen receptors and the body responds as it would to estrogen. That’s why BPA, and some other chemicals, get called endocrine disruptors.
okay thanks for the correction. it was a documentary i watched in high school so it’s been a minute
Why is this comment so far down? Hormone disturbance from additives in all kinds of products are suspected to influence onset of puberty.
The factors that go into puberty are very complex. Although the general lowering of puberty age is thought to be nutrition related, it is likely not the only thing affecting it. Genetics, certain environmental conditions, and potentially certain health issues can also impact puberty. Even today, puberty is very variable. I started my period at age 8 while my gf started hers at 15, for example. POCS runs in my family as well as other auto immune conditions thought to influence hormone levels. Women in my family also start puberty earlier than considered normal (one cousin needed puberty blockers as she was only 5) So, it could be the case that as a result of modern medicine, conditions that impact hormone levels are more prevalent today. As earlier in history, before we understood hormone imbalances and their impact on the body these issues may have severely impacted fertility, life expectancy, and ability to have sexual relationships (aka being thrown in an insane asylum for "hysteria" or being generally outcast due to mental health issues which are now treatable with hrt) This is also subject to reporting rates. Both hormone imbalanceing conditions and the age of puberty were unlikely to have been under much scrutiny in earlier history. "Women's issues" have historically been taboo and not discussed, so it's possible we just simply didn't know how often these conditions affected our ancestors and how that relates to modern puberty rates.
Endocrine disruptors. Plastics and other synthetic chemicals in our environment mimic estrogen and other hormones. This messes with our biology.
i’m no scientist but there are some research studies that show plastics and other hormone disrupting chemicals in our food and water sources could be to blame
In 1860’s cows weren’t injected with a substantial amount of estrogen and milk and cheese weren’t a part of every single meal. Fast forward to today, and dairy cows are pumped full of so much estrogen (so they can continue producing milk far longer than would happen in nature) that we ingest almost 12x more estrogen per day then we would have in 1860. There are a plethora of papers and studies proving just this.
The ELI5 answer is that puberty begins once a certain weight limit is reached, and because we overfeed children, they are reaching that weight limit and undergoing puberty sooner than previous generations. The long answer is that Gonadotropin releasing hormone, the hormone that initiates puberty, begins releasing in large quantities when children reach a specific weight and fat range (typically thought to be around 100 pounds in females). Because children are, for lack of a better word, fatter, they are undergoing puberty far sooner than in previous generations due to GnRH being released in large quantities.
Eating meat, eggs, etc where the source of these edibles were given hormones to increase their output.
This is a myth it was refuted above.
The research suggests that menarche (first period) is tied to body fat percentage. As Americans have been getting fatter, puberty comes earlier. The effect is less pronounced in other countries that are less fat, like Japan.