thanks for providing insight into the actual literature, and for clearly indicating why there are no studies of teenage sperm counts in normal individuals.
Your recitation of Kennedy's copious conflicts of interest was alone worth the price of admission. This is a kakistocracy chock full of the worst possible people. Hell, cabinet meetings alone have three rapists sitting at the table, including Mr. Sperm Count Kennedy.
Dr. Angela thank you for the humourous & factual rebuttal of one of RFK Jr's latest misrepresentations of scientific information.
Akin to his buffoon BBF aka DJT who similarly spouts unsubstantiated scientific misinformation, your readers are fortunate, yourself & others with knowledge, expertise & compassion counter their BS.
I have no vote in the USA but I have a fiduciary duty to remain current & knowledgeable to offer a rebuttal to the garage that gets repeated north of the 43rd parallel.
Until the elected members of the American Congress & Senate find the courage to push back against Trump & his feckless sycophants, we can remain hopeful those who understand the science & have no "conflicts of interest" other than the wellbeing of their fellow citizens will remain resolute in speak truth to power, albeit the latter is veiled 🤔
I posted on another site that I was never a supporter of New York's "Off-Track Betting," which are "parlors" for wagering during that sport's season. But when they elect a new mayor, I fully intend to lobby hard for a new betting category, "New Loony Assertions from the Secretary of HHS." By the way, this assertion that teens were experiencing lowering sperm counts has been circulating in the pre-MAGA circuit for several years.
Angela, you are something else. We need more people like you. In a way, hellscape events open our eyes to flaws in our society. The question is can we survive this version to fix it. Or does it have to fully collapse to start over.
Thank you for this great analysis. I’m not really surprised that the reference doesn’t match the claim, just disappointed. I did a deep dive into food dyes on my Substack because of RFK’s attack on them and claim that they cause ADHD and autism. The MAHA report linked to a meta-analysis. But when I found it, it was a non peer reviewed book chapter review of research that specifically stated, “…there is no evidence of a link between food dyes and autism.” So disappointing.
Even if the results of the meta analysis were correct sperm counts were still well above the level necessary for conception and therefore couldn’t explain decreases in fertility. There is little doubt that decreases in fertility are a consequence of increasing wealth and a world in which governments (society if you prefer), rather than family, provide support in old age.
But let’s go back to sperm counts. I think a much more plausible explanation of the data is that availability and use of porn has increased massively over the time period studied. Now I don’t know what researchers such as Levine think those men are doing, but without strong evidence that the samples are coming from men who have abstained for at least 7 or 8 days you are not going to have comparable data. You can try to adjust in the regression but there’s a lot of missing data and to be blunt if you ask a man about abstinence how likely is it that you get an accurate answer when even his wife doesn’t know. I don’t have enough interest to do it myself but I think an analysis of what abstinence data is available from the studies and how sensitive the results are to changes in that data would be interesting.
Finally this is a more recent and less sensational paper regarding US data
Lewis K, Cannarella R, Liu F, Roth B, Bushweller L, Millot J, Kuribayashi S, Kuroda S, Aguilar Palacios D, Vij SC, Cullen J, Lundy SD. Sperm concentration remains stable among fertile American men: a systematic review and meta-analysis. Fertil Steril. 2025 Jan;123(1):77-87. doi: 10.1016/j.fertnstert.2024.08.322. Epub 2024 Aug 14. PMID: 39128669.
Wow. Mad writing. You really broke it down. RFK Jr will prove his incompetence and unwillingness to change, or even consider the hard science.
Anti-Science is something we have to get over as culture. It’s ridiculous and embarrassing. Especially when the world looks on.
RFK is telling everyone and anyone that he has no amount of education and immediately started the blame game.
And Trump. Omg. He says, with an incredibly proud smile how he touched himself some other people could have his kids. He is literally proud to have spent decades with dick in hand. Jeez. The things these people take pride in.
I am sitting here grinning like a buzzard on a shitwagon at your excellent takedown of this very deserving person masquerading as someone with expertise that is capable of being in charge of our health. You are my hero!
Ever since I read Rachel Carson's "Silent Spring" I have always been wary of exposure to chemicals - specially when gardening (over time I have used what was once approved but now banned from use). I am still a relatively healthy boomer.
Thankfully we no longer have the sales promotion of the past (someone once actually drank a glass of a chemical in a commercial) to show the so called safety of chemicals and the impact on health from exposure - either at work or at home.
I worked in the chemical industry in a number of roles - including product safety. The profit motive behind new product introduction creates enormous pressure on getting the product into the market and the regulatory assessments needed to show impacts are enormously complicated by the test and statistical proof needed.
I believe the European Chemical Agency (ECHA) approach of using the precautionary principle - where the risk assessment is done up front - before commercial approval is the right one but regulators are behind the curve in risk assessment - just from the sheer volume of new chemicals being introduced into the market.
Right now ECHA lists 140 chemicals as endocrine disruptors, 250 as substances of very high concern and numerous others such as biocides and Nanomaterials still awaiting analysis and reporting under the ECHA for toxicity and reproductive impacts.
Ever since Silent Spring was published - the late 1950's - there have been an untold number of new chemicals introduced into the market place and the workplace - so I can understand how the impact studies can be misconstrued and used to agitate the public.
Even with my extensive chemical knowledge I wonder if I am really safe from all the multiple exposures I face daily- currently from the nanoparticles and micro-plastics found in my food, water and sunscreen. I wonder who is looking at all that exposure instead of sperm counts!
That is a lot of sticky data to comb through. Perhaps Hegseth should be advised as he may be interested in pairing that with testosterone levels, and, possibly he already has a high interest level in sperm, as might RFK, Jr. The soldiers involved are going to have to consider the fatigue factor.
thanks for providing insight into the actual literature, and for clearly indicating why there are no studies of teenage sperm counts in normal individuals.
Your recitation of Kennedy's copious conflicts of interest was alone worth the price of admission. This is a kakistocracy chock full of the worst possible people. Hell, cabinet meetings alone have three rapists sitting at the table, including Mr. Sperm Count Kennedy.
“Our parent aren’t having children”. Uh …..
Dr. Angela thank you for the humourous & factual rebuttal of one of RFK Jr's latest misrepresentations of scientific information.
Akin to his buffoon BBF aka DJT who similarly spouts unsubstantiated scientific misinformation, your readers are fortunate, yourself & others with knowledge, expertise & compassion counter their BS.
I have no vote in the USA but I have a fiduciary duty to remain current & knowledgeable to offer a rebuttal to the garage that gets repeated north of the 43rd parallel.
Until the elected members of the American Congress & Senate find the courage to push back against Trump & his feckless sycophants, we can remain hopeful those who understand the science & have no "conflicts of interest" other than the wellbeing of their fellow citizens will remain resolute in speak truth to power, albeit the latter is veiled 🤔
JJF Phm 🇨🇦
I posted on another site that I was never a supporter of New York's "Off-Track Betting," which are "parlors" for wagering during that sport's season. But when they elect a new mayor, I fully intend to lobby hard for a new betting category, "New Loony Assertions from the Secretary of HHS." By the way, this assertion that teens were experiencing lowering sperm counts has been circulating in the pre-MAGA circuit for several years.
Angela, you are something else. We need more people like you. In a way, hellscape events open our eyes to flaws in our society. The question is can we survive this version to fix it. Or does it have to fully collapse to start over.
Thank you for this great analysis. I’m not really surprised that the reference doesn’t match the claim, just disappointed. I did a deep dive into food dyes on my Substack because of RFK’s attack on them and claim that they cause ADHD and autism. The MAHA report linked to a meta-analysis. But when I found it, it was a non peer reviewed book chapter review of research that specifically stated, “…there is no evidence of a link between food dyes and autism.” So disappointing.
Even if the results of the meta analysis were correct sperm counts were still well above the level necessary for conception and therefore couldn’t explain decreases in fertility. There is little doubt that decreases in fertility are a consequence of increasing wealth and a world in which governments (society if you prefer), rather than family, provide support in old age.
But let’s go back to sperm counts. I think a much more plausible explanation of the data is that availability and use of porn has increased massively over the time period studied. Now I don’t know what researchers such as Levine think those men are doing, but without strong evidence that the samples are coming from men who have abstained for at least 7 or 8 days you are not going to have comparable data. You can try to adjust in the regression but there’s a lot of missing data and to be blunt if you ask a man about abstinence how likely is it that you get an accurate answer when even his wife doesn’t know. I don’t have enough interest to do it myself but I think an analysis of what abstinence data is available from the studies and how sensitive the results are to changes in that data would be interesting.
Finally this is a more recent and less sensational paper regarding US data
Lewis K, Cannarella R, Liu F, Roth B, Bushweller L, Millot J, Kuribayashi S, Kuroda S, Aguilar Palacios D, Vij SC, Cullen J, Lundy SD. Sperm concentration remains stable among fertile American men: a systematic review and meta-analysis. Fertil Steril. 2025 Jan;123(1):77-87. doi: 10.1016/j.fertnstert.2024.08.322. Epub 2024 Aug 14. PMID: 39128669.
What a fantastic comment — beautifully written and full of insight. Thanks
Wow. Mad writing. You really broke it down. RFK Jr will prove his incompetence and unwillingness to change, or even consider the hard science.
Anti-Science is something we have to get over as culture. It’s ridiculous and embarrassing. Especially when the world looks on.
RFK is telling everyone and anyone that he has no amount of education and immediately started the blame game.
And Trump. Omg. He says, with an incredibly proud smile how he touched himself some other people could have his kids. He is literally proud to have spent decades with dick in hand. Jeez. The things these people take pride in.
I am sitting here grinning like a buzzard on a shitwagon at your excellent takedown of this very deserving person masquerading as someone with expertise that is capable of being in charge of our health. You are my hero!
Your logical emissions are as penetrating as your capacity for subtle euphemism.
Bravo!
Ever since I read Rachel Carson's "Silent Spring" I have always been wary of exposure to chemicals - specially when gardening (over time I have used what was once approved but now banned from use). I am still a relatively healthy boomer.
Thankfully we no longer have the sales promotion of the past (someone once actually drank a glass of a chemical in a commercial) to show the so called safety of chemicals and the impact on health from exposure - either at work or at home.
I worked in the chemical industry in a number of roles - including product safety. The profit motive behind new product introduction creates enormous pressure on getting the product into the market and the regulatory assessments needed to show impacts are enormously complicated by the test and statistical proof needed.
I believe the European Chemical Agency (ECHA) approach of using the precautionary principle - where the risk assessment is done up front - before commercial approval is the right one but regulators are behind the curve in risk assessment - just from the sheer volume of new chemicals being introduced into the market.
Right now ECHA lists 140 chemicals as endocrine disruptors, 250 as substances of very high concern and numerous others such as biocides and Nanomaterials still awaiting analysis and reporting under the ECHA for toxicity and reproductive impacts.
Ever since Silent Spring was published - the late 1950's - there have been an untold number of new chemicals introduced into the market place and the workplace - so I can understand how the impact studies can be misconstrued and used to agitate the public.
Even with my extensive chemical knowledge I wonder if I am really safe from all the multiple exposures I face daily- currently from the nanoparticles and micro-plastics found in my food, water and sunscreen. I wonder who is looking at all that exposure instead of sperm counts!
That is a lot of sticky data to comb through. Perhaps Hegseth should be advised as he may be interested in pairing that with testosterone levels, and, possibly he already has a high interest level in sperm, as might RFK, Jr. The soldiers involved are going to have to consider the fatigue factor.
No ylab(, angle(0)), no credibility
Yes there are some studies like this. Not very many and not enough to make comparisons across age groups at population level.