For people interested in knowing (roughly) their own sperm count, you can use a hemocytometer and a cheap ~600x microscope (like the kid science kit ones) to measure your own. It's basically measuring overall volume, putting some on the slide, and counting so many squares. Then multiple that count to get to the 1ml volume based on the volume of the squares and them multiple by overall number of ml. And paying attention to how many are moving vs not to get an idea of motility.
Would have appreciated if they had included references to credible work that shows "Male infertility is on the rise" & "significant declines in sperm quantity and quality occurring across the human population worldwide in the past two decades" rather than taking it as an accepted fact.
See Shanna Swan and the Count Down book. This effect is already established, many of the mechanisms are established, science is discovering more mechanisms, but we already know enough to start taking public health actions.
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
I mean, it's been called "survival of the fittest" since as long as I can remember.
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.
The opening paragraph reads like something straight out of "Children of Men"[a]:
> 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 ...
Not sure of a specific one. I think RO removes it. Also, I think NAS has started certifying filters that remove PFAS. You can test your water for PFAS to see if you need one too. Sometimes the source of PFAS is from ones own plumbing and not the supply (if your supplier has a test that has lower levels than your home).
Generally a good activated carbon filter will get most of it. If you’re feeling particularly paranoid, a reverse osmosis filter will produce extremely clean water. So clean that there are disagreements about whether it will actually leach some of the salts and minerals back out from your body.
Peak conventional was 2008, it's hard(er) to make plastic from non-conventional oil, and plastic from plant don't need phtalates (at least PLA doesn't, i know there is other kind of plastic but i don't know about them).
This comes up every now and then, and I take a look at some research and it always seems pretty clear that it's obesity.
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.
BPA/BPB in plastics is another source. Unfortunately, this one is basically unavoidable since even if one doesn't own any of those plastics at home, there's bound to be some food product that uses a plastic container. Even more so, we don't know anything about how long it takes to leach into the food, what plastics do/don't contain it, stuff like that.
Plastics should just be banned from touching food entirely.
If you have running water in your home, every drop likely flows through hundreds of feet to miles of plastic pipe before you drink it. Even if you have a private well and copper plumbing, your pump and other components almost always contain plastic parts that make contact with the water.
I think it really depends on the food. Like processed or skinned meat absorbs more than seeds or dry food, frozen absorbs less, or something like that. I haven't read about it for a while but that's what I remember was kind of like the consensus about where to start looking into if it's feasible to ban BPA.
An interesting series of articles that came up on HN a couple months ago makes the argument that both infertility and obesity arise from environmental contaminates (although not necessarily phthalates). Regardless of whether you agree with the arguments presented, I think it’s really interesting to see just how complex of a problem it is to figure out what’s going on.
I don't particularly buy it. Again, sure, maybe it has a statistically significant effect, but it is undoubtedly dwarfed by people chugging sugary drinks and being more sedentary. A casual search suggests sugar consumption has increased 9 fold since the 1800s and 2 fold since the 1900s. The poor in particular are cornered into purchasing sugary foods due to weird economics around corn subsidies. And what do you know? They're the fattest by far.
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.
Well, if we control the epidemics of sedentarism and obesity doesn't follow, those complex causes may be worth investing on. But we have a very simple pair of problems (bad nutrition and sedentarism) that are able to explain more than all the obesity around without any need for a contributing cause.
(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.)
The second article in the series cites a 25% increase in calories consumed during the period where obesity is rising, but then tries to wave that away as inconsequential.
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.
It does seem painfully simple that consuming more energy than you burn/excrete is going to turn you into a sink, and a lot of that surplus energy is going to be stored as fat. (And the opposite process applies when you consume less than you use.)
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?
I read that blog series and it makes a decent case that there is some environmental contaminant that matters (or a combination of several), but it can't be the whole story because things like gastric bypass definitely work. Also just from observing obese people eat it is clear that few of them eat in a way conducive to weight loss. Perhaps some environmental contaminant causes them to crave calorically dense, non-satiating foods, but that seems doubtful to me.
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.
Incidents like this, small remote populations along the Amazon in Brazil rapidly becoming fat when given access to nestle food; make me think it's just the food (in practical terms).
People who eat meat and animal fat and cut out sugar report getting pregnant after years of not being able to. They also report iso-caloric weight loss, resolution of diabetes 2, thickening of hair and many other positive health heuristics. Obesity, diabetes and metabolic considerations are an absolute powder-keg of medical progress just waiting for mainstream acceptance
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.
That's an interesting idea, but I'm not sure the anatomy lines up. Like the mass of belly fat and fatty liver pressing down from above in upright humans resting on the pudendal artery wouldn't be the same as how the mass hangs on quadrupeds. This is an interesting line of thought too, like what organs get compressed under gravity from increased mass assuming it's primarily a mechanical problem.
I'm not talking about anatomy, but rather physiology (obesity affects hormones related to sperm). Do you have some information to suggest this is an anatomical issue (other than sleep apnea) rather than physiological one?
nothing specific other than speculating about hearing about stuff around that bottom part of the body: lower sperm count, slower bowel movements with constipation and stuff. I wonder if there's anything else anatomical down there that could potentially get disrupted from extra mass bearing down on it.
I thought I remember reading it is dropping across the line, including for fit and healthy individuals. Is that not right, and if it is, what could that mean?
I can recall only one article that was posted here which included that, but I came away thinking it was misleading. It binned weight categories(e.g. BMI ranges from X-Y) and showed that over time, people were falling into heavier categories, and that sperm outcomes were getting worse in every category (heavily in the obese, less so in the normal weight range). But if you eyeballed the curve it felt very likely that the distribution of individuals was just shifting the the heavier end within each category.
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.
If obesity it perhaps should be studied as a realtime pushback against modern diets by nature/natural selection, in reducing unhealthy people from the gene pool.
Risks for cardiovascular disease, stroke, cancer, and of course diabetes, are all significantly increased with obesity. Risk of getting severe covid-19 is significant increased with obesity.
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.
Or perhaps the correlation between obesity and low fertility is not causation, obesity could very well be a symptom of whatever is causing it, alongside low fertility.
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.
From a purely observation perspective, pornography consumption has increased dramatically at the same time as falling fertility. Even if a mechanism isn't obvious, it at least seems like there is a possibility of a connection.
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.
The lower cost of sexual release in porn leading to less motivation to pursue relationships with the opposite sex, an activity which in our current state of reproductive preferences, moral values and technology is strongly correlated with instances of human reproduction.
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.
I think "lack of fertility" to design low sperm count/inviable spermatozoids is accurate. Lack of virility would be impossibility to use your own penis for different reasons. 10-8 year ago i knew a trans who was fertile and could give sperm to her lesbian friends, but lacked virility.
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.
There's no evidence that japan has lower testosterone than an average country. The only study I could find suggested it had a higher average than the US.
That supports what others have commented, which is that obesity is likely the main culprit, at least in terms of low testosterone. The US has a much worse obesity problem than Japan does.
I don't see why, there's a physiological basis for it. It's well known that fat cells have higher level of aromatase which converts testosterone to estradiol.
As others have said: sedentary lives in front of screens, declining nutrition and rising obesity are all culprits. Western media loves to gawk at Japan from a cultural perspective but I would be careful about drawing social parallels there. It's easy to cherry-pick social trends to confirm bias one way or another. But the physical and material conditions people live in are very tangible and demonstrably unhealthy.
> Men are made to be dumb, reckless and horny, the moment they become cerebral, emotional and scared that's the signal that society is on the brink of collapse.
This statement is wholly unsupported by history or science.
Those "experiments" have long since been recognized as broken and invalid. The mice were severely overcrowded, because Calhoun didn't actually understand the animals' need for spread out, large territories, and was more concerned with churning out dozens of ridiculous mouse-panopticons.
Mice have biological processes that are sometimes analogous to humans, making them useful for some forms of experimentation. Their social behavior is anything but human-like.
That is because when you look closely at factors that led to those wars, you find people reacting on self interest in situations where going to war is has high chance of being beneficial to them.
It is easy to create slogans and such. But real history when you look at it is not as simple as dumb guys being dumb.
If past performance is not an indicator of future outcomes than why did you reference history(the past) in your last point to reinforce what you think will be happening in our future?
So say the NIH finds that some compounds in our environment that get in our bodies are causing this. Leeching from plastic food containers, chemical pesticides, soy, whatever it is. What do you think is going to happen? The government is almost certainly not going to destroy it's chemical or agriculture industries to prevent this. No matter the findings nothing will come of it.
It's easy to say that but look at the reduction in smoking over the last 20 years... it was unimaginable that the government would crack down and actively reduce smoking and cigarette accessibility and advertising but it did once the magnitude of the harm was recognized and accepted.
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.
We're in a Utopia. Utopias destroy purpose. Without purpose intelligence can not exist, so the rate of apoptosis surpasses the rate of reproduction. Obesity is a symptom of this, not the cause.
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."
The "study" is horrifying because the mice were severely overcrowded, and suffered some extreme psychological breakdowns as a result. Not because it can predict human behavior and socialization in any way. 2,200 mice stuffed in a 10'x14' pen? It's insanity. It's not even possible to make an analogy for humans, because humans are fundamentally social, across individuals and family units and more, in a way that mice are not.
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 mice choose to put 2,200 of them into that small environment. The researcher wasn't forcing them to procreate, just giving them sufficient food to do so.
The effects would have been just as surprising if only 100 of 50 mice were involved.
I don’t think we’re in a utopia. Most people do have food, comfort, and safety. But most don’t have much free time (jobs), good relationships, clean air, and an overall lack of stress (plenty of things to worry about). Maybe we live in a society like Universe 25, but it isn’t a utopia.
Life is better than it used to be, but it’s far from perfect.
