My belief is that the primary cause is environmental chemicals, specifically Phthalates and BPA (and related chemicals). The science on this is fairly conclusive. We can show that these chemicals bind to estrogen receptors, that they're present in everyone's body, and that if you're acutely exposed to a higher dose, your testosterone goes down. In my opinion, these chemicals are having social and cultural effects bey…
The linkage between consumption of these chemicals, and their exact nature of harm, is not well established- it's not "fairly conclusive" at all. What we have is a bunch of in vitro and in vivo studies, but not actual epidemiological evidence of the quality required to make rational policy decisions. If you believe otherwise, I'm happy to ready any high quality studies you can find. Pleaes don't just cherry pick a fe…
Just picking articles at random, I don't have time for a full literature review for Hacker News, but the evidence taken in totality is overwhelming:
1. BPA (and related chemicals) activate estrogen receptors, causal study: https://www.ncbi.nlm.nih.gov/pubmed/28407500 This has been repeatedly demonstrated.
2. Direct human effects, correlational study: Working in a factory with BPA makes you impotent: http://www.oxfordjournals.org/news/dep381.pdf
3. Direct human effects, correlational study: BPA exposure by parents, especially mothers leads to reduced anogenital distance in children: https://www.ncbi.nlm.nih.gov/pubmed/21987463
4. Direct human effects, correlational: BPA and other EDCs are associated with penile defects: http://www.acmt.net/_Library/PEHSU_Webinars/Is_Hypospadias_A...
5. Human ingestion routes, correlational: Blood BPA levels are highest occupationally among cashiers (thermal receipts), and people who eat a lot of canned vegetables (plastic can liners): https://www.ncbi.nlm.nih.gov/pubmed/21205581
There are loads more where that came from. You've got a very direct mechanism of action, clear effects in animal models, and correlational studies showing people who are exposed to larger quantities show clear medical problems. You have clear, understandable routes of ingestion, and correlational data that shows that people who are exposed more to those routes of ingestion have more in their blood. I suppose you can complain that the human studies are correlational, but you can't legally perform a blinded study on this, because we know that BPA is harmful, and you won't get it past an IRB. Maybe you formed your opinion on this in the nineties or 2000s when only the hippies were trading out their nalgene bottles, but the science has come a long way, and the hippies were right. Phthalates are a very similar story.