9 ms·

Sperm Count in Western Men Has Dropped Over 50 Percent Since 1973, Paper Finds

105 points by acdanger 9y ago

RichardHeart 9y ago
Could this be from progress in pornography?
- locacorten 9y ago
  If this were an important factor, I would expect to see the same drop in non-Western countries. Porn is global. The data doesn't show a significant decrease outside the West.
- ovao 9y ago
  It's a fair question. I don't know of any correlation between an increase in porn-viewing and decreased sperm counts.
  - zumu 9y ago
    From what I understand, regular masturbation can decrease sperm count temporarily. But it will come back to normal within 2-3 days of cessation. This is what I've found from googling around, but I didn't stumble upon a definitive source. So make of this what you will.
- seandoe 9y ago
  was wondering the same thing. Not from some complex, hormonal thing, but more like men are possibly masturbating a lot more with porn's technological progress. Are the studies controlled for sex/masturbation frequency? ...whoops, I guess the study did account for it.
- 110011 9y ago
  It's sad that perhaps the most plausible (of the discussed reasons so far in this thread) is being downvoted. I guess people believe what they want to believe. Anecdotally, I have felt (and sounded) a whole better ever since I stopped consuming porn. There is also a very real drive and stubbornness that I feel in myself, markedly higher than before. I would chalk (without evidence but as a hypothesis) decreased levels of T to: - not working out (and having a desk job), - increased consumption of porn, - harmful substances in mass produced food that we don't understand fully.
  - ge96 9y ago
    I mean... If you stopped for a week would you have more? Or is it the same everyday haha.
byproxy 9y ago
Are we headed into a "Children of Men" scenario?
- petermcneeley 9y ago
  Children of men was infertility of women.
  - markcerqueira 9y ago
    The novel the movie was based upon used male infertility. Movie switched that and pinned the infertility on females. That said, infertility on the man or woman doesn't matter much in a "we want to make babies scenario." The end result is the same: a world like that in The Children of Men.
hyperdunc 9y ago
I've noticed over the last 20 or so years that men in the West, in general, appear increasingly effeminate. I've also noticed that a lot of male pop stars have really high voices. I've long suspected these observations are more than cultural. Recent studies seem to back this intuition.
- ekianjo 9y ago
  Is there a direct correlation between sperm count and appearance though? Its probably more relevant to consider testosterone.
- ovao 9y ago
  Effeminate by what attributes?
  - PrimHelios 9y ago
    Western cultural values, I guess. This seems to be a really weird talking point of the right wing (although I'm not saying that it's only the right, or that hyperdunc is right wing), that people have stopped caring about hyper-masculinity, and it must be caused by hormones and not just a change in cultural values.
- algesten 9y ago
  In the 1700s castratis were quite popular throughout Europe. Does that mean they had low sperm count then, or was it just something people liked? I really don't believe you can explain cultural phenomenon through medical science.
  - emersonrsantos 9y ago
    Castrati means literally castrated, normally boys before puberty to retain the soprano/mezzo-soprano pitch on adulthood. This got forbidden in 1870 in Italy and by the Roman church in 1902.
  - phamilton 9y ago
    castratis have exceptionally low sperm count
Tycho 9y ago
Is this result beyond dispute? No chance it's just a problem with the measurements/methodology?
- kirrent 9y ago
  Not beyond dispute at all. There's a huge number of confounding factors involved in comparing all the different datasets used over the time period concerned. One example is that older tests famously overestimated sperm counts. Additionally, many of the older data is from observational studies of people presenting at early fertility clinics. This paper attempts to control those factors and while I haven't seen any particular criticism of their methods it's an incredibly difficult problem to deal with. Especially when sperm count appears to be so responsive to small environmental variations to begin with. It'll be interesting to see more research in the field, probably spurred on by this study. Questions that need to be answered include, why only Western countries? Does that imply a correlation between technological development and fertility? What are the trends in Korea and Japan looking like considering they modernised a while before many of their neighbours? Halving counts sounds like a lot, but it isn't really and teasing out the ultimate causes is probably going to be incredibly difficult.
- jonnycomputer 9y ago
  My first thought was whether this could be an artifact of evolving measurement methods or changes in sampling. Another possibility is that baseline was actually higher than normal, because maybe it fluctuates depending on context (e.g. under certain stressors like war time). Or maybe we are just seeing the pr0n effect.
chrisreichel 9y ago
I was surprised to see Brazil, Chile and Mexico categorized as 'Non-Western countries'.
- nextstep 9y ago
  Yeah I saw that too... I don’t understand. Is Western a political definition?
  - oculusthrift 9y ago
    The term 'west' outdates the discovery of America and no longer has anything to do with Geography. It used to mean western Europe. Now it essentially means western Europe, canada, australia, and america. All of which have cultural roots in Western europe and liberalism etc.
    - emmelaich 9y ago
      Yep, and "South" is a somewhat archaic term to refer to developing countries. Australia is not of the "South" despite being in the southern hemisphere.[1] It's also weird to refer to the Asian countries north-west of Australia as "Far East"; though that usage is also fading. [1] https://en.wikipedia.org/wiki/North%E2%80%93South_divide https://en.wikipedia.org/wiki/North%E2%80%93South_divide
  - vacri 9y ago
    'western' means 'west european and similar', not 'western hemisphere'. It basically means most of europe (now) and the anglo 'new world' countries, though the exact countries involved vary depending on who is doing the defining.
- pcurve 9y ago
  Here's a map of Western countries. https://en.wikipedia.org/wiki/Western_world#/media/File:The_Western_World.png https://en.wikipedia.org/wiki/Western_world#/media/File:The_...
  - 9y ago
derping69 9y ago
BPA, birth control/estrogen in water, and increased obesity rates would be my guess.
- jkelsey 9y ago
  Interesting. Could you elaborate?
- emersonrsantos 9y ago
  Exogenous testosterone also lowers sperm count.
- imron 9y ago
  Not to mention estrogen from plastics: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/
- PrimHelios 9y ago
  >birth control/estrogen in water Is that actually a thing? I didn't find any sources definitively showing it was enough to warrant a concern.
  - azr79 9y ago
    women take birth control they pee and flush this water gets processed and re injected back into the pipes if you make the mistake to drink the tap water where they re purpose it from the canalisations, you just drink birth control water.
    - AstralStorm 9y ago
      Data to back it up please? As far as I know the hormones used have quite short half life in decent conditions. Much less metabolites.
    - xaqfox 9y ago
      Sounds like you have a local water supply problem if they serve you recycled sewage (or a regretful plumbing problem).
paulcole 9y ago
Anxiously awaiting the first comment on the feminizing effects of soy...
- marze 9y ago
  Here you go: http://www.menshealth.com/nutrition/soys-negative-effects http://www.menshealth.com/nutrition/soys-negative-effects
  - emersonrsantos 9y ago
    And the counter argument: http://ussec.org/wp-content/uploads/2015/10/SOY13_7_Soy-and-Mens-Health.pdf http://ussec.org/wp-content/uploads/2015/10/SOY13_7_Soy-and-...
  - waterhouse 9y ago
    In particular, the article says: "In a Harvard study published last year in the journal Human Reproduction, Jorge E. Chavarro, M.D., Sc.D., and his colleagues found a strong association between men’s consumption of soy foods and decreased sperm counts." The study in question seems to be this: https://academic.oup.com/humrep/article/23/11/2584/2913898/Soy-food-and-isoflavone-intake-in-relation-to https://academic.oup.com/humrep/article/23/11/2584/2913898/S... "The intake of 15 soy-based foods in the previous 3 months was assessed for 99 male partners of subfertile couples who presented for semen analyses to the Massachusetts General Hospital Fertility Center. ... There was an inverse association between soy food intake and sperm concentration that remained significant after accounting for age, abstinence time, body mass index, caffeine and alcohol intake and smoking. In the multivariate-adjusted analyses, men in the highest category of soy food intake had 41 million sperm/ml less than men who did not consume soy foods." (For reference, various sources say anywhere from 20 to 150 million sperm/ml is average.) Contrariwise, the Wiki article on soy points to this meta-study (from four years before the above): https://www.ncbi.nlm.nih.gov/pubmed/20378106 https://www.ncbi.nlm.nih.gov/pubmed/20378106 "Clinical evidence also indicates that isoflavones have no effect on sperm or semen parameters, although only three intervention studies were identified and none were longer than 3 months in duration." Here's another from a few months after the meta-study: https://www.ncbi.nlm.nih.gov/pubmed/19819436 https://www.ncbi.nlm.nih.gov/pubmed/19819436 That last one seems to be a randomized controlled study, where they gave a bunch of college men either milk protein or one of two variants of soy protein. I don't know if there's anything in soy that isn't in the "soy protein isolates" from the last study. If there isn't, then the last study seems like strong evidence. The first one could conceivably come down to some sort of selection bias.
AndrewKemendo 9y ago
Previously: https://news.ycombinator.com/item?id=14855796 https://news.ycombinator.com/item?id=14855796 As I said in that thread, this is another statistic that had a rapid and precipitous change starting in the early 1970s. I've stated this elsewhere, but it's like something(s) happened the late 60s/early 70s that totally transformed our world and I have no clue what they were nor can I find anyone who has written about it. Wealth inequality [1], Real Wage stagnation [2], Obesity Rates [3], Divorce Rates [4] [1] http://inequality.stanford.edu/sites/default/files/Pathways-SOTU-2016-Wealth-Inequality-3.pdf http://inequality.stanford.edu/sites/default/files/Pathways-... [2] http://www.epi.org/publication/charting-wage-stagnation/ http://www.epi.org/publication/charting-wage-stagnation/ [3] http://az616578.vo.msecnd.net/files/2015/11/20/6358359882436216361965175721_obese.gif http://az616578.vo.msecnd.net/files/2015/11/20/6358359882436... [4] http://www.stateofourunions.org/2009/si-divorce.php http://www.stateofourunions.org/2009/si-divorce.php
- yters 9y ago
  1965 is when birth control pills became legal.
  - bane 9y ago
    It's also about the time that High Fructose Corn Syrup started to be shipped in bulk. HFCS-55 in particular became the dominant sweetener in soda sometime during the late 1970s. The late 70s was also the introduction of video games and home computers. A general explosion of electronic devices has permeated almost everywhere. Unleaded gas was introduced in 1974. What replaced lead as the antiknock agent? The space race? Here's a 1966 video by NASA on toxic propellants. https://www.youtube.com/watch?v=ND2TeNfcmKA https://www.youtube.com/watch?v=ND2TeNfcmKA
    - bonzini 9y ago
      Re. lead tetraethyl, unleaded gas has more benzene than leaded one as a side effect of the productive process, but the answer is more complicated. Benzene is only released in the environment when the engine is cold. The "replacement" for lead tetraethyl is a combination of better valves, higher octane rating when gasoline is produced, and electronic control of spark plugs. There's some feedback between these too, for example improved burning of fuel and the introduction of catalytic converter lets you increase the octane rating without suffering increased pollution from benzene.
marze 9y ago
Can anyone summarize the various theories developed to explain this decline?
- Deestan 9y ago
  The ones I have read while scrolling to this comment: 1. Jet fuel 2. Sugar 3. Plastics 4. Space Rockets 5. The gays
  - JPLeRouzic 9y ago
    Thanks, you can add changes in body's probiotics and water contamination. Water contamination is my favorite, animals share water with us and it is treated with obsolete technologies (and people fantasize about springs and pure aquiferes when it is mostly about recycling used water or polluted water from rivers and swamps)
innovate 9y ago
could we be simply better at doing these tests? eg more accuracy today vs ~44yrs ago?
roceasta 9y ago
I find this fascinating. It's an important biological phenomenon and we don't know if it's due to culture or to chemistry.
cmurf 9y ago
Something in the water or the milk? Something basic enough that a significant majority is in contact, but culturally distinct enough that a significant minority elsewhere are not in contact.
nocoder 9y ago
The phathalates hypothesis sounds plausible to me. However, it will be a combination of factors social, economical and biological. One hypothesis, I have been thinking of is about relation between the age of the father when the child was conceived and it's correlation with sperm count of the child when he grows up. I am not sure if this data was collected in the study. Does anyone know about any such study?
teekert 9y ago
Quote from article (meant as response to AndrewKemendo): "Phthalates are a group of chemicals used to make plastics more flexible and harder to break. In several studies over the last two decades, they have been shown to disrupt the operation of male hormones like testosterone and have been linked to genital birth defects in male infants. Dr. Swan, who conducted a 2008 study about phthalate exposure, said that scientists have had the ability to measure exposure to plasticizers only since about 2000, via urine. That has led to a 20-year lag in the process since researchers cannot enroll men to produce sperm until they are in their 20s. That evidence is the “missing piece of the puzzle,” she said." Here in the Netherlands several partie are trying ot get hormone disturbing substances on the political agenda but even BPA is apparently not even illegal here. There was even a show where they measured BPA in the urine of politicians and still, very little attention is given to such substances. [0] [https://radar.avrotros.nl/uitzendingen/gemist/14-11-2016/hormoonverstorende-stoffen-in-urine-kamerleden/ https://radar.avrotros.nl/uitzendingen/gemist/14-11-2016/hor...]
- adrianN 9y ago
  Another problem is that if you ban BPA you have to replace it with something else that makes plastics less brittle. It's completely unclear whether the replacement chemical will be better or worse. Almost all chemicals we use industrially are untested.
  - AstralStorm 9y ago
    Albeit if you do not need durability or huge oil resistance you can go very far with silicone tubing which does not need plasticizers. Nobody likes the expense or maintenance though.
whizzkid 9y ago
My theory goes like this; > In the recently released research, no significant decline in sperm quality was seen in men from non-Western countries, but this segment made up only about a quarter of the results. There is something in developed countries that the male do not experience during his lifetime. It can be lack of fear, adrenalin, less activity, or something else. I think statistics hold up with the historic wars as well. As WW2 ends and people starts living without any fear of life, male sperm quality drops. I think it is about what male experiences and which hormons are triggered in his lifetime.
- pasquinelli 9y ago
  that sounds magical.
  - AstralStorm 9y ago
    It is easily testable. Take samples of war veterans.
    - whizzkid 9y ago
      Not sure if it helps though. It has been so long since they have experienced a tough life, levels may already gone back to same levels as others.
29052017 9y ago
This thread is hilarious
stephen82 9y ago
One word: stress.
cameldrv 9y ago
I think it's pretty clear that Phthalates are a big piece of the puzzle. Here's the chain of evidence: I just picked one study for every link, but there are many for each. People have significant levels of Phthalates in their blood: http://www.ourstolenfuture.org/NewScience/oncompounds/phthalates/2003/2003-0101kochetal.htm http://www.ourstolenfuture.org/NewScience/oncompounds/phthal... People who have higher levels of Phthalates in their blood tend to have lower testosterone: http://www.medscape.com/viewarticle/830137 http://www.medscape.com/viewarticle/830137 There are several pathways how Phthalates might cause this to happen in the human body, including: https://www.ncbi.nlm.nih.gov/pubmed/26385792 https://www.ncbi.nlm.nih.gov/pubmed/26385792 Testosterone levels in Men have been dropping about 1% per year for at least the past 20 years, about the same rate as sperm counts: https://www.healio.com/endocrinology/hormone-therapy/news/print/endocrine-today/%7Bac23497d-f1ed-4278-bbd2-92bb1e552e3a%7D/generational-decline-in-testosterone-levels-observed https://www.healio.com/endocrinology/hormone-therapy/news/pr... Low Testosterone causes low sperm count: https://www.ncbi.nlm.nih.gov/pubmed/6772497 https://www.ncbi.nlm.nih.gov/pubmed/6772497
- Tharkun 9y ago
  Have there been any studies on how to reduce phthalate levels in humans? Does limiting exposure help? Can the body expell the stuff?
  - AstralStorm 9y ago
    1) pilot studies. 2) it is very hard to limit exposure, they're too widespread. The main effects happen in childhood and adolescence. They may last for life. 3) not clear and not studied, but likely yes. This might not help at all like with many endocrine toxins that act on development.
  - cameldrv 9y ago
    I know of one, fairly questionable study that showed that you could reduce Phthalates in your blood by about 50% by eliminating processed food, never storing or heating food in plastic, and switching to Phthalate free personal care products. There have been a few studies that have shown that the main route of exposure is through ingestion. Processed foods are more likely to contain Phthalates, probably because the ingredients may have flowed through PVC tubing that leaches them. It's really impossible to know, but the fewer processing steps your food has gone through, the less chance that this has happened. The biggest industrial use of Phthalates is as a plasticizer, and they are present in several types of plastic, in large quantities. Heating food in plastic containers has the potential to volatilize Phthalates and leach them into your food. This is a particular risk in prepared frozen food that you microwave. Many personal care products, such as soaps, shampoos, deodorants, and perfumes, contain Phthalates. Try to find ones that don't. One particularly bad source of exposure is certain enteric coated medicines and supplements. I would strongly advise anyone to not take anything that is enteric coated unless you know what the coating is made of. Some pills can spike Phthalate levels by 50x in a single dose. Almost all foods that contain animal fat will contain Phthalates, and this is a big source of exposure. Milk, meat, cheese, etc, all contain them, as they are fat soluble. The good news is that your body seems to clear these chemicals fairly quickly, but the problem is that you're constantly exposed to them. Ultimately, these are chemicals that we've produced over a billion tons of. It's just not possible to avoid them entirely. If you have a baby on the way though, make sure that the new mom does everything she can to minimize exposure, as what happens during that time really can never be taken back.
DKnoll 9y ago
I can no longer sit back and allow Communist infiltration, Communist indoctrination, Communist subversion, and the international Communist conspiracy to sap and impurify all of our precious bodily fluids.
techaddict009 9y ago
What does Western Men means exactly? (I am from India so asking.) As every country has their own west. Does this mean West of US? Or West of whole world?
- romanovcode 9y ago
  EU + USA
  - hawski 9y ago
    ... + Canada + Australia
visarga 9y ago
In other news, population still rising.
- txmx2000 9y ago
  Decellerating worldwide and decreasing within a couple of decades.
- deleted 9y ago
  [deleted]
ge96 9y ago
Man that's messed up about the plastic. Everytime I heat up food in plastic now at my job I will think some guy out there I'm killing his sperm. Ahh the sugar too man... Alright will try to keep that in mind when eating/shopping. Soda though, it's what keeps me awake/engaged at work, coke it's nasty as hell but... There is also unsweetened tea, I don't know if it's too strong, seems to have the opposite effect of feeling more alert. Often I go to work without sleep but that's my own problem, that's why I look forward to being self employed haha.
MicroBerto 9y ago
Atrazine.... And all the other endicrine disruptors. Packaged food is literally toxic at this point.
chewz 9y ago
Perhaps the Nature is starting to fight back against explosion of human population and associated damage.

105 points by acdanger 9y ago

RichardHeart 9y ago

Could this be from progress in pornography?

locacorten 9y ago
If this were an important factor, I would expect to see the same drop in non-Western countries. Porn is global. The data doesn't show a significant decrease outside the West.
ovao 9y ago
It's a fair question. I don't know of any correlation between an increase in porn-viewing and decreased sperm counts.
- zumu 9y ago
  From what I understand, regular masturbation can decrease sperm count temporarily. But it will come back to normal within 2-3 days of cessation. This is what I've found from googling around, but I didn't stumble upon a definitive source. So make of this what you will.
seandoe 9y ago
was wondering the same thing. Not from some complex, hormonal thing, but more like men are possibly masturbating a lot more with porn's technological progress. Are the studies controlled for sex/masturbation frequency? ...whoops, I guess the study did account for it.
110011 9y ago
It's sad that perhaps the most plausible (of the discussed reasons so far in this thread) is being downvoted. I guess people believe what they want to believe. Anecdotally, I have felt (and sounded) a whole better ever since I stopped consuming porn. There is also a very real drive and stubbornness that I feel in myself, markedly higher than before. I would chalk (without evidence but as a hypothesis) decreased levels of T to: - not working out (and having a desk job), - increased consumption of porn, - harmful substances in mass produced food that we don't understand fully.
- ge96 9y ago
  I mean... If you stopped for a week would you have more? Or is it the same everyday haha.

byproxy 9y ago

Are we headed into a "Children of Men" scenario?

petermcneeley 9y ago
Children of men was infertility of women.
- markcerqueira 9y ago
  The novel the movie was based upon used male infertility. Movie switched that and pinned the infertility on females. That said, infertility on the man or woman doesn't matter much in a "we want to make babies scenario." The end result is the same: a world like that in The Children of Men.

hyperdunc 9y ago

I've noticed over the last 20 or so years that men in the West, in general, appear increasingly effeminate. I've also noticed that a lot of male pop stars have really high voices. I've long suspected these observations are more than cultural. Recent studies seem to back this intuition.

ekianjo 9y ago
Is there a direct correlation between sperm count and appearance though? Its probably more relevant to consider testosterone.
ovao 9y ago
Effeminate by what attributes?
- PrimHelios 9y ago
  Western cultural values, I guess. This seems to be a really weird talking point of the right wing (although I'm not saying that it's only the right, or that hyperdunc is right wing), that people have stopped caring about hyper-masculinity, and it must be caused by hormones and not just a change in cultural values.
algesten 9y ago
In the 1700s castratis were quite popular throughout Europe. Does that mean they had low sperm count then, or was it just something people liked? I really don't believe you can explain cultural phenomenon through medical science.
- emersonrsantos 9y ago
  Castrati means literally castrated, normally boys before puberty to retain the soprano/mezzo-soprano pitch on adulthood. This got forbidden in 1870 in Italy and by the Roman church in 1902.
- phamilton 9y ago
  castratis have exceptionally low sperm count

Tycho 9y ago

Is this result beyond dispute? No chance it's just a problem with the measurements/methodology?

kirrent 9y ago
Not beyond dispute at all. There's a huge number of confounding factors involved in comparing all the different datasets used over the time period concerned. One example is that older tests famously overestimated sperm counts. Additionally, many of the older data is from observational studies of people presenting at early fertility clinics. This paper attempts to control those factors and while I haven't seen any particular criticism of their methods it's an incredibly difficult problem to deal with. Especially when sperm count appears to be so responsive to small environmental variations to begin with. It'll be interesting to see more research in the field, probably spurred on by this study. Questions that need to be answered include, why only Western countries? Does that imply a correlation between technological development and fertility? What are the trends in Korea and Japan looking like considering they modernised a while before many of their neighbours? Halving counts sounds like a lot, but it isn't really and teasing out the ultimate causes is probably going to be incredibly difficult.
jonnycomputer 9y ago
My first thought was whether this could be an artifact of evolving measurement methods or changes in sampling. Another possibility is that baseline was actually higher than normal, because maybe it fluctuates depending on context (e.g. under certain stressors like war time). Or maybe we are just seeing the pr0n effect.

chrisreichel 9y ago

I was surprised to see Brazil, Chile and Mexico categorized as 'Non-Western countries'.

nextstep 9y ago
Yeah I saw that too... I don’t understand. Is Western a political definition?
- oculusthrift 9y ago
  The term 'west' outdates the discovery of America and no longer has anything to do with Geography. It used to mean western Europe. Now it essentially means western Europe, canada, australia, and america. All of which have cultural roots in Western europe and liberalism etc.
  - emmelaich 9y ago
    Yep, and "South" is a somewhat archaic term to refer to developing countries. Australia is not of the "South" despite being in the southern hemisphere.[1] It's also weird to refer to the Asian countries north-west of Australia as "Far East"; though that usage is also fading. [1] https://en.wikipedia.org/wiki/North%E2%80%93South_divide https://en.wikipedia.org/wiki/North%E2%80%93South_divide
- vacri 9y ago
  'western' means 'west european and similar', not 'western hemisphere'. It basically means most of europe (now) and the anglo 'new world' countries, though the exact countries involved vary depending on who is doing the defining.
pcurve 9y ago
Here's a map of Western countries. https://en.wikipedia.org/wiki/Western_world#/media/File:The_Western_World.png https://en.wikipedia.org/wiki/Western_world#/media/File:The_...
- 9y ago

derping69 9y ago

BPA, birth control/estrogen in water, and increased obesity rates would be my guess.

jkelsey 9y ago
Interesting. Could you elaborate?
emersonrsantos 9y ago
Exogenous testosterone also lowers sperm count.
imron 9y ago
Not to mention estrogen from plastics: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/
PrimHelios 9y ago
>birth control/estrogen in water Is that actually a thing? I didn't find any sources definitively showing it was enough to warrant a concern.
- azr79 9y ago
  women take birth control they pee and flush this water gets processed and re injected back into the pipes if you make the mistake to drink the tap water where they re purpose it from the canalisations, you just drink birth control water.
  - AstralStorm 9y ago
    Data to back it up please? As far as I know the hormones used have quite short half life in decent conditions. Much less metabolites.
  - xaqfox 9y ago
    Sounds like you have a local water supply problem if they serve you recycled sewage (or a regretful plumbing problem).

paulcole 9y ago

Anxiously awaiting the first comment on the feminizing effects of soy...

marze 9y ago
Here you go: http://www.menshealth.com/nutrition/soys-negative-effects http://www.menshealth.com/nutrition/soys-negative-effects
- emersonrsantos 9y ago
  And the counter argument: http://ussec.org/wp-content/uploads/2015/10/SOY13_7_Soy-and-Mens-Health.pdf http://ussec.org/wp-content/uploads/2015/10/SOY13_7_Soy-and-...
- waterhouse 9y ago
  In particular, the article says: "In a Harvard study published last year in the journal Human Reproduction, Jorge E. Chavarro, M.D., Sc.D., and his colleagues found a strong association between men’s consumption of soy foods and decreased sperm counts." The study in question seems to be this: https://academic.oup.com/humrep/article/23/11/2584/2913898/Soy-food-and-isoflavone-intake-in-relation-to https://academic.oup.com/humrep/article/23/11/2584/2913898/S... "The intake of 15 soy-based foods in the previous 3 months was assessed for 99 male partners of subfertile couples who presented for semen analyses to the Massachusetts General Hospital Fertility Center. ... There was an inverse association between soy food intake and sperm concentration that remained significant after accounting for age, abstinence time, body mass index, caffeine and alcohol intake and smoking. In the multivariate-adjusted analyses, men in the highest category of soy food intake had 41 million sperm/ml less than men who did not consume soy foods." (For reference, various sources say anywhere from 20 to 150 million sperm/ml is average.) Contrariwise, the Wiki article on soy points to this meta-study (from four years before the above): https://www.ncbi.nlm.nih.gov/pubmed/20378106 https://www.ncbi.nlm.nih.gov/pubmed/20378106 "Clinical evidence also indicates that isoflavones have no effect on sperm or semen parameters, although only three intervention studies were identified and none were longer than 3 months in duration." Here's another from a few months after the meta-study: https://www.ncbi.nlm.nih.gov/pubmed/19819436 https://www.ncbi.nlm.nih.gov/pubmed/19819436 That last one seems to be a randomized controlled study, where they gave a bunch of college men either milk protein or one of two variants of soy protein. I don't know if there's anything in soy that isn't in the "soy protein isolates" from the last study. If there isn't, then the last study seems like strong evidence. The first one could conceivably come down to some sort of selection bias.

AndrewKemendo 9y ago

Previously: https://news.ycombinator.com/item?id=14855796 https://news.ycombinator.com/item?id=14855796 As I said in that thread, this is another statistic that had a rapid and precipitous change starting in the early 1970s. I've stated this elsewhere, but it's like something(s) happened the late 60s/early 70s that totally transformed our world and I have no clue what they were nor can I find anyone who has written about it. Wealth inequality [1], Real Wage stagnation [2], Obesity Rates [3], Divorce Rates [4] [1] http://inequality.stanford.edu/sites/default/files/Pathways-SOTU-2016-Wealth-Inequality-3.pdf http://inequality.stanford.edu/sites/default/files/Pathways-... [2] http://www.epi.org/publication/charting-wage-stagnation/ http://www.epi.org/publication/charting-wage-stagnation/ [3] http://az616578.vo.msecnd.net/files/2015/11/20/6358359882436216361965175721_obese.gif http://az616578.vo.msecnd.net/files/2015/11/20/6358359882436... [4] http://www.stateofourunions.org/2009/si-divorce.php http://www.stateofourunions.org/2009/si-divorce.php

yters 9y ago
1965 is when birth control pills became legal.
- bane 9y ago
  It's also about the time that High Fructose Corn Syrup started to be shipped in bulk. HFCS-55 in particular became the dominant sweetener in soda sometime during the late 1970s. The late 70s was also the introduction of video games and home computers. A general explosion of electronic devices has permeated almost everywhere. Unleaded gas was introduced in 1974. What replaced lead as the antiknock agent? The space race? Here's a 1966 video by NASA on toxic propellants. https://www.youtube.com/watch?v=ND2TeNfcmKA https://www.youtube.com/watch?v=ND2TeNfcmKA
  - bonzini 9y ago
    Re. lead tetraethyl, unleaded gas has more benzene than leaded one as a side effect of the productive process, but the answer is more complicated. Benzene is only released in the environment when the engine is cold. The "replacement" for lead tetraethyl is a combination of better valves, higher octane rating when gasoline is produced, and electronic control of spark plugs. There's some feedback between these too, for example improved burning of fuel and the introduction of catalytic converter lets you increase the octane rating without suffering increased pollution from benzene.

marze 9y ago

Can anyone summarize the various theories developed to explain this decline?

Deestan 9y ago
The ones I have read while scrolling to this comment: 1. Jet fuel 2. Sugar 3. Plastics 4. Space Rockets 5. The gays
- JPLeRouzic 9y ago
  Thanks, you can add changes in body's probiotics and water contamination. Water contamination is my favorite, animals share water with us and it is treated with obsolete technologies (and people fantasize about springs and pure aquiferes when it is mostly about recycling used water or polluted water from rivers and swamps)

innovate 9y ago

could we be simply better at doing these tests? eg more accuracy today vs ~44yrs ago?

roceasta 9y ago

I find this fascinating. It's an important biological phenomenon and we don't know if it's due to culture or to chemistry.

cmurf 9y ago

Something in the water or the milk? Something basic enough that a significant majority is in contact, but culturally distinct enough that a significant minority elsewhere are not in contact.

nocoder 9y ago

The phathalates hypothesis sounds plausible to me. However, it will be a combination of factors social, economical and biological. One hypothesis, I have been thinking of is about relation between the age of the father when the child was conceived and it's correlation with sperm count of the child when he grows up. I am not sure if this data was collected in the study. Does anyone know about any such study?

teekert 9y ago

Quote from article (meant as response to AndrewKemendo): "Phthalates are a group of chemicals used to make plastics more flexible and harder to break. In several studies over the last two decades, they have been shown to disrupt the operation of male hormones like testosterone and have been linked to genital birth defects in male infants. Dr. Swan, who conducted a 2008 study about phthalate exposure, said that scientists have had the ability to measure exposure to plasticizers only since about 2000, via urine. That has led to a 20-year lag in the process since researchers cannot enroll men to produce sperm until they are in their 20s. That evidence is the “missing piece of the puzzle,” she said." Here in the Netherlands several partie are trying ot get hormone disturbing substances on the political agenda but even BPA is apparently not even illegal here. There was even a show where they measured BPA in the urine of politicians and still, very little attention is given to such substances. [0] [https://radar.avrotros.nl/uitzendingen/gemist/14-11-2016/hormoonverstorende-stoffen-in-urine-kamerleden/ https://radar.avrotros.nl/uitzendingen/gemist/14-11-2016/hor...]

adrianN 9y ago
Another problem is that if you ban BPA you have to replace it with something else that makes plastics less brittle. It's completely unclear whether the replacement chemical will be better or worse. Almost all chemicals we use industrially are untested.
- AstralStorm 9y ago
  Albeit if you do not need durability or huge oil resistance you can go very far with silicone tubing which does not need plasticizers. Nobody likes the expense or maintenance though.

whizzkid 9y ago

My theory goes like this; > In the recently released research, no significant decline in sperm quality was seen in men from non-Western countries, but this segment made up only about a quarter of the results. There is something in developed countries that the male do not experience during his lifetime. It can be lack of fear, adrenalin, less activity, or something else. I think statistics hold up with the historic wars as well. As WW2 ends and people starts living without any fear of life, male sperm quality drops. I think it is about what male experiences and which hormons are triggered in his lifetime.

pasquinelli 9y ago
that sounds magical.
- AstralStorm 9y ago
  It is easily testable. Take samples of war veterans.
  - whizzkid 9y ago
    Not sure if it helps though. It has been so long since they have experienced a tough life, levels may already gone back to same levels as others.

29052017 9y ago

This thread is hilarious

stephen82 9y ago

One word: stress.

cameldrv 9y ago

I think it's pretty clear that Phthalates are a big piece of the puzzle. Here's the chain of evidence: I just picked one study for every link, but there are many for each. People have significant levels of Phthalates in their blood: http://www.ourstolenfuture.org/NewScience/oncompounds/phthalates/2003/2003-0101kochetal.htm http://www.ourstolenfuture.org/NewScience/oncompounds/phthal... People who have higher levels of Phthalates in their blood tend to have lower testosterone: http://www.medscape.com/viewarticle/830137 http://www.medscape.com/viewarticle/830137 There are several pathways how Phthalates might cause this to happen in the human body, including: https://www.ncbi.nlm.nih.gov/pubmed/26385792 https://www.ncbi.nlm.nih.gov/pubmed/26385792 Testosterone levels in Men have been dropping about 1% per year for at least the past 20 years, about the same rate as sperm counts: https://www.healio.com/endocrinology/hormone-therapy/news/print/endocrine-today/%7Bac23497d-f1ed-4278-bbd2-92bb1e552e3a%7D/generational-decline-in-testosterone-levels-observed https://www.healio.com/endocrinology/hormone-therapy/news/pr... Low Testosterone causes low sperm count: https://www.ncbi.nlm.nih.gov/pubmed/6772497 https://www.ncbi.nlm.nih.gov/pubmed/6772497

Tharkun 9y ago
Have there been any studies on how to reduce phthalate levels in humans? Does limiting exposure help? Can the body expell the stuff?
- AstralStorm 9y ago
  1) pilot studies. 2) it is very hard to limit exposure, they're too widespread. The main effects happen in childhood and adolescence. They may last for life. 3) not clear and not studied, but likely yes. This might not help at all like with many endocrine toxins that act on development.
- cameldrv 9y ago
  I know of one, fairly questionable study that showed that you could reduce Phthalates in your blood by about 50% by eliminating processed food, never storing or heating food in plastic, and switching to Phthalate free personal care products. There have been a few studies that have shown that the main route of exposure is through ingestion. Processed foods are more likely to contain Phthalates, probably because the ingredients may have flowed through PVC tubing that leaches them. It's really impossible to know, but the fewer processing steps your food has gone through, the less chance that this has happened. The biggest industrial use of Phthalates is as a plasticizer, and they are present in several types of plastic, in large quantities. Heating food in plastic containers has the potential to volatilize Phthalates and leach them into your food. This is a particular risk in prepared frozen food that you microwave. Many personal care products, such as soaps, shampoos, deodorants, and perfumes, contain Phthalates. Try to find ones that don't. One particularly bad source of exposure is certain enteric coated medicines and supplements. I would strongly advise anyone to not take anything that is enteric coated unless you know what the coating is made of. Some pills can spike Phthalate levels by 50x in a single dose. Almost all foods that contain animal fat will contain Phthalates, and this is a big source of exposure. Milk, meat, cheese, etc, all contain them, as they are fat soluble. The good news is that your body seems to clear these chemicals fairly quickly, but the problem is that you're constantly exposed to them. Ultimately, these are chemicals that we've produced over a billion tons of. It's just not possible to avoid them entirely. If you have a baby on the way though, make sure that the new mom does everything she can to minimize exposure, as what happens during that time really can never be taken back.

DKnoll 9y ago

I can no longer sit back and allow Communist infiltration, Communist indoctrination, Communist subversion, and the international Communist conspiracy to sap and impurify all of our precious bodily fluids.

techaddict009 9y ago

What does Western Men means exactly? (I am from India so asking.) As every country has their own west. Does this mean West of US? Or West of whole world?

romanovcode 9y ago
EU + USA
- hawski 9y ago
  ... + Canada + Australia

visarga 9y ago

In other news, population still rising.

txmx2000 9y ago
Decellerating worldwide and decreasing within a couple of decades.
deleted 9y ago
[deleted]

ge96 9y ago

Man that's messed up about the plastic. Everytime I heat up food in plastic now at my job I will think some guy out there I'm killing his sperm. Ahh the sugar too man... Alright will try to keep that in mind when eating/shopping. Soda though, it's what keeps me awake/engaged at work, coke it's nasty as hell but... There is also unsweetened tea, I don't know if it's too strong, seems to have the opposite effect of feeling more alert. Often I go to work without sleep but that's my own problem, that's why I look forward to being self employed haha.

MicroBerto 9y ago

Atrazine.... And all the other endicrine disruptors. Packaged food is literally toxic at this point.

chewz 9y ago

Perhaps the Nature is starting to fight back against explosion of human population and associated damage.