Sperm Count in Western Men Has Dropped over 50% Since 1973, Paper Finds (2017) | Hacker News Reader

Sperm Count in Western Men Has Dropped over 50% Since 1973, Paper Finds (2017)

nytimes.com

69 pointsgiansegato26 comments

It's a real shame that so many of our datasets start out in the middle of the 20th century when people used atmospheric nuclear tests to light cigarettes [0] and then drove home in their lead gasoline fueled trucks to eat in lead painted dining rooms food grown under the protection of DDT. I would guess if one looked at the chemical environment for all of human history, somewhere between 1950 and 1970 would probably be the absolute furthest from the baseline.

[0] https://www.wearethemighty.com/mighty-history/physicist-lit-...

Neither radiation nor lead nor DDT have these kinds of effects. The most likely scenario are endocrine disrupters in the form of any number of industrial chemicals introduced over the 20th and 21st centuries. The EPA has no protocols or rules for detecting if a new chemical is an endocrine disrupter. There are also no protocols for long-term mental effects. It's simply not tested for, there is no currently known ways of doing so and there are no laws requiring it anyway.

So the average case is quite contaminated and later generations enjoy it either directly or indirectly. I recently went down the rabbit hole but I decided to mind my own business for the moment. I think pretty much every spot on earth around that timeframe with some growing economy had under-earthly environmental standards. Certain cancer rates having increased over time is really deterministic from that point of view.

Leaded gas has still been in production and use up till this year 2021. Its finally gone though.

Isn't some of the propeller airplane gasoline still leaded? Isn't it even worse as it's sprayed on top of us?

You are right I missed that. Even worse its like 90% rich people just tooling around in their hobby plane while literally crop dusting the area with poison. Strange how nobody talks about that yet as simple as the solution is.

Just watched an interesting presentation by Shanna Swan, who has a book out on this exact topic[0]. I haven't looked into the veracity of her claims but basically her argument is as follows:

TL;DR - its chemicals in the environment, particularly those that disrupt hormone production in utero.

- Sperm count and testerone levels having been falling at a rate of about ~1% per year. This also coincides with cases of miscarriage and erectile disfunction rising at a rate of about ~1% per year.

- This suggests something is affecting the human reproductive system.

- Three possible factors could include genetics (not likely since the change is too rapid to be evolutionary), lifestyle (certainly a factor), and but also potentially environmental

- Hormonal disruption from environmental chemicals has the most lasting effect when children are in utero, particularly any chemicals altering testosterone production. Testosterone is important because, biologically, female is the default. In the absence of sufficient levels of testosterone in utero, male children will have underdeveloped masculine traits (biologically, not psychologically).

- One measure of underdeveloped masculine traits is anogenital distance (look it up, but not at work if your really curious). Phthalates is one class of chemical that has been demostrated in rats to disrupt in utero testosterone production and reduce anogenital distance. There is growing evidence this also occurs in humans.

- Phthalates are used extensively in a number of products, including food products (basically anything with soft plastic)

- Other classes of chemicals exist which also disrupt hormone function. These hormone disruptors have an even more pronounced effect when combined together.

[0] https://youtu.be/Uo-kSxHNSDQ

I know that increased numbers of fat cells can lead to estrogen production in men. I kind of wonder how these reproductive issues plot with respect to obesity.

I have no evidence for this but I wonder whether, in the more sexist/male-dominated society of the 70s and early 80s, it was more common for doctors to deliver reports to men that did not question their own "virility" when assessing fertility problems.

Note that a lot of these alarming studies/articles focus on sperm count while this is only one of the 3 important factors for healthy sperm. The others being motility and shape. I dont know if count is disproportionately more important than the other 2 though.

Nobody seems to mention EMF

RF-EMF exposure negatively affects sperm quality.

The influence of direct mobile phone radiation on sperm quality

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4074720/

The Effects of Exposure to Low Frequency Electromagnetic Fields on Male Fertility

http://www.clevelandclinic.org/reproductiveresearchcenter/do...

Effect of electromagnetic field exposure on the reproductive system

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6240172/#:~:tex....

and many more...

Samples are mostly from men that already have problems with fertility. Helthy mens probably wont give samples for studies etc. So those general conclusions are not valid so much.

Where's the source for your "mostly"? And you're arguing against a study with "probably"?

That's not a compelling argument.

I don't think you can say that and that would be controlled for anyway.

Ban all plastics from ever touching food/water. This problem will go away overnight.

Silver bullets rarely work, but even if this was the singular root cause, and it were possible to enact and enforce such a ban - it will probably take multiple generations. And that assumes this problem doesn't involve epigenetics - it could be hereditary.

Don't forget about PFAS.

Not really. There's also estrogens from birth control, for instance.

Ban all internet porn. This problem will go away overnight.

can someone non-lazy provide link to the study?

This has been widely disputed take it all with a grain of salt , https://news.harvard.edu/gazette/story/2021/05/fears-over-fa...

That article doesn’t say anything disputing the main result about lowered sperm counts. Rather, it

- Questions whether there is a causal link between lowered sperm count and lowered fertility.

- Declares the design of the original study racist because it categorizes countries as “Western” and “Other”

- Expresses concern that aspects of the study could be used by alt-right white supremacists for their own agendas.

They then propose an alternative framework to conduct this research, but from what I can tell did no science of their own.

Links like that are just PR fluff written by university admin/funding departments. We should hardly ever link those; link the actual research paper instead: https://academic.oup.com/humupd/article/23/6/646/4035689

Ugh thank you I couldnt find it.

Another example of an experiment widely criticized is the Milgram Experiment (where you trick people into thinking they are electrocuting and eventually killing other people).

But the criticism is of the methods used being unethical - nobody is disputing the conclusions of the research (that more than half of the public will knowingly kill someone else when instructed to do so by a scientist they have only known for 15 minutes).

There is a link in the first paragraph

https://academic.oup.com/humupd/article/23/6/646/4035689

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