NIH-funded research to address rising male infertility
news.cornell.edu
news.cornell.edu
The epi evidence is clear and the mechanisms behind several exposure like phthalates have been established in animal studies and human epidemiological studies.
notable are:
1. The question of declining sperm density revisited: an analysis of 101 studies published 1934-1996.
2. Environmental phthalate exposure in relation to reproductive outcomes and other health endpoints in humans
It's still turning out to be true, even with all our 21st century medical knowledge of science. Healthy at every size? Not if you want to procreate!
It's weird. I absolutely love the feeling of "I knew this was very likely true and didn't need a study to prove it" and have a study come out that proves my hunch was mostly correct or on the right path. Probably some kind of suuuper duper biased positive feedback loop but something like this just totally makes sense to me. If you don't take care of your body, then things are going to start breaking down earlier than expected.
> Male infertility is on the rise, with significant declines in sperm quantity and quality occurring across the human population worldwide in the past two decades. The reason for this is poorly understood, but scientists suspect ...
Hmm...
https://www.usatoday.com/story/news/2021/02/27/falling-sperm...
edit: the phthalates comes up every time. Yeah it does seem to have some effect, but the effect sizes found in papers doesn't seem to be that huge, meanwhile the effect size of obesity is very large, and the prevalence of it is observably growing rapidly. You also have to consider that the people with the most bioaccumulant shit like this are the people with large reserves of fatty tissue to absorb it.
Studies have indicated that long-term pornography use correlates with erectile dysfunction and loss of interest in sexual relationships. It's not hard to imagine that fertility might be related to these other aspects of reproductive health. Unfortunately few long-term studies seem to focus on fertility specifically.
Short term studies on the influence of porn find that novel sexual stimulus seems to increase sperm quality while it attenuates in response to repeated exposure to the same stimulus. This is bad news for real life humans who cannot change as rapidly or dramatically as one can switch videos.
Indeed ... wasn't it supposed to cause blindness?
P.S. The use of "fertility" to describe men is weird and seems recent. Fertility is passive and receptive and thus better fits women (hence the use in agriculture to describe the earth). Virility is a better term because it is active. Some people seem to falsely claim that it doesn't refer to procreative or generative power, but it does as this entry in Etymology Online[0] shows (emphasis mine):
"period of manhood," 1580s, from French virilité, from Latin virilitatem (nominative virilitas) "manhood," from virilis "of a man, manly, worthy of a man," from vir "a man, a hero," from PIE root wi-ro- "man." Meaning "power of procreation, capacity for sexua[l] intercourse" is from 1590s; sense of "manly strength" is recorded from c. 1600.
There's not much power to procreate if you have a low sperm count.
[0] https://www.etymonline.com/word/virility#etymonline_v_30873
The female counterpart of virility should be femininity.
DNA and knowledge of the specific of procreation is probably as recent as the use of fertility.
Wanted to comment about obesity but i guess most people said what i wanted to say, so i'm rebounding on a tangent for my own self-esteem, sorry.
But If I was a researcher, I would stay clear of using a term that could be understood as some kind of endorsement of toxic masculinity, heteronormativity or whatever.
Better to use the slightly less accurate term, overloading its original meaning with a new one, and avoid being the subject of a witch hunt.
https://slimemoldtimemold.com/2021/07/07/a-chemical-hunger-p...
If it were mostly environmental you'd see broader gains. variation. But in my little bubble in upper middle class Massachusetts, I don't know ANYONE who is obese. In other areas of the country it's hard to find anyone who isn't.
(Anyway, the odds that there isn't any contributing cause on the tons of changes we made on the world are pretty small, and it's important to study those for individual health. It's just for societal health that there's no mystery to solve.)
It seems obvious that obesity is the result of the increased caloric intake with secondary effects from the increasingly sedentary lifestyles we all lead.
Environmental toxins might play a tertiary role, but it’s definitely the calories driving most of the obesity issue.
Is this an oversimplification, or is the average education/propaganda/understanding so confused, and so overwhelmed with different nutrition ideas that the wood is being missed for the trees?
Edit: The other thing I noticed when reading the series was that the author had a habit of discounting anything that refuted his thesis (calling it a minor effect and so forth), while giving greater credibility to similarly weak evidence for his theory.
https://wearemitu.com/wearemitu/things-that-matter/nestle-fl...
Plastics should just be banned from touching food entirely.
Sorry for lack of source, it’s not my area.
E.g. if a healthy BMI is 18-25, and you look at the the average outcome for that group over time... if the whole population gets fatter then the mean value in the 18-25 group could shift from 20 to 22. So... take it as you will. Sorry for no source here either.
The obesity thing tends to hold across many other species too. I would guess you are right about this being the main driver. A classic example would be dealing with animal husbandry and obese pigs. Fertility in obese females can be impacted too.
A variety of toxins have been shown to cause fertility issues too, such as lead and pesticides. It's also possible that estrogen and estrogen mimicking compounds found in drinking water could fall into this category (estrogen can adversely affect male fertility).
Testoterone is also a factor which has seen a large decline over the last 50 years. Obesity and sedentary lifestyle can cause a decline in testorerone and other hormones/enzymes related to sperm.
Then there's a possible link to RF reducing sperm quality. Although I think this is probably a secondary factor that might exacerbate the others.
https://www.hsph.harvard.edu/news/hsph-in-the-news/excess-we...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3521747/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5657098/
You can find more without much effort. What I don't see are epidemiological studies trying to track the prevalence of obesity vs. the average sperm quality across different nations. Unfortunately.
I know plenty of relatively wealthy people who are fat or even skinny fat (arguably worse condition), it's not only about access to reasonable nutrition.
I don't think cigarettes are comparable to agriculture products and plastics and other chemicals because all of those things serve other purposes, they have economic uses. It's one thing to crack down on something that all it does is fleece people til they die painfully from it, it's another thing entirely to retool material production around a health concern.
This is Universe 25:
> According to Calhoun, the extinction consisted of two stages: the “first death” — characterized by the loss of purpose in life beyond mere existence (including the loss of desire to mate, raise young, or establish a role within society) — and “second death” marked by the literal end of life and the extinction of Universe 25.
> "Males who failed withdrew physically and psychologically; they became very inactive and aggregated in large pools near the center of the floor of the universe. From this point on they no longer initiated interaction with their established associates, nor did their behavior elicit attack by territorial males," read the paper. "Even so, they became characterized by many wounds and much scar tissue as a result of attacks by other withdrawn males."
https://historyofyesterday.com/the-horrifying-study-that-pre...
It's ridiculous pseudo-science that's taken at face-value as presented by Calhoun only because it makes an empty clickbait article sound deep.
The effects would have been just as surprising if only 100 of 50 mice were involved.
Life is better than it used to be, but it’s far from perfect.