> “This study shows that paternal exercise can confer benefits — enhanced endurance and metabolic health — to offspring,”
So good habits can be good for offspring.
> For instance, mouse fathers exposed to nicotine(opens a new tab) sire male pups with livers that are good at disarming not just nicotine but cocaine and other toxins as well.
So bad habits can be good for offspring.
> “We just don’t have really any understanding of how RNAs can do this, and that’s the hand-wavy part,”
It seems to me to all be the handwavy part. I'm happy to wait until the research is considerably further advanced, past the clickbait stage.
But that's not what it says. RNA fragments are entering the ovum and having some sort of effect .... that's quite different from passing traits the way genes on chromosomes do.
Some trees have mechanisms, for instance, where they die quickly but signal other trees if exposed to certain issues, allowing the other trees to put up a better defense.
Ants and other insects sometimes do the same thing.
the section immediately after that you didn’t quote:
> evidence keeps piling up. Most recently, in November 2025, a comprehensive paper (opens a new tab) published in Cell Metabolism traced the downstream molecular effects of a father mouse’s exercise regimen on sperm microRNAs that target genes “critical for mitochondrial function and metabolic control” in a developing embryo. The researchers found many of those same RNAs overexpressed in the sperm of well-exercised human men.
I and others generally don't quote things that aren't relevant to the point we're making and I'm not keen on the crypt-accusation. I didn't say that there aren't downstream molecular effects--clearly there are. Rather, the article is very unclear about the nature of epigenetics, and the wording about "transmitting traits" is misleading at best and leads to many unwarranted conclusions, as evidenced in the comments here. The statements I quoted are not about transmitting traits. e.g., "paternal exercise" refers to a trait of exercising, taking time to exercise, being motivated to exercise, etc. The "conferred benefit" of "enhanced endurance and metabolic health" is a different trait. If that is the trait being transmitted then that should be the trait being identified in male parents, not "exercise". Similarly, being exposed to nicotine is not the trait of having livers that are good at "disarming" nicotine, cocaine, and a host of other toxins ... and this is an extraordinary claim that requires extraordinary evidence, and the article provides one citation, from 2017.
And as an epigeneticist says in the article, we have no idea how RNA is having the effects its having.
As I said, I'm happy to wait until we have moved beyond this early stage of research before making any radical inferences.
In the “paternal exercise” case the trait isn’t the habit of exercising, it’s the metabolic changes of exercise that are (apparently) conferred to both father and offspring.
You're completely missing the point that I explicitly stated. The trait that is purportedly being transmitted is metabolic changes that confer some advantage, but that's not what's being measured in the father, "exercise" is--not a word was said about fathers having better metabolic health, just that they "exercise". Which is reason to be skeptical of the claim.
Have you considered that checking for that specifically might not be actually needed? After all, the correlation between exercise and metabolic health is well established.
That was my original thought, however if you want to quantify an effect it would be ideal to measure the same trait in both parent and offspring. I assume that the reason that this was done (I didn’t read the papers) is because this is a retrospective study, where the participants self-report on the exercise level of their fathers, rather than a longitudinal study which could measure the fathers’ metabolic state fitness at time of conception.
Thus, although there is a plausible link, I now agree with the parent post that this is sufficient reason to take the study with a grain of salt (given well known academic incentives to produce positive results, etc).
Theres huge uncertainty and layered assumptions in all of microbiology and biochemistry about how exactly things work on small scale. Because it is really hard to study live reactions in little things you can just barely see on an electron microscope.
But yet humanity has managed to assert statistical truths about for example genetics and explain countless diseases, even cure and alleviate some. So even if you don’t have a theory on how exactly something works from the ground up, if you have statistical evidence, plenty of useful and practical advances can be built top-bottom and we have outcomes that validate this.
Not giving any opinion on this piece specifically but just saying there can be scientific value even if the details are hand-wavy.
> The point is that people are drawing all sorts of unwarranted conclusions from this lay report on early stage research.
That is partly because no one seems willing to summarize this work, in concise form, for nonspecialists. Such a summary might be, "This is an important finding, but it doesn't mean Lysenko was right, and the term 'inheritance' doesn't have just one meaning."
I think the term "inheritance" for both DNA and epigenetic information transfers (as in the linked article) is innately confusing.
I agree. The example with Nicotine intake having a somewhat positive effect on the children feels too wild at the money. Think of all the kids of the 60th and 70th. They must be immune to most toxins ;). Yes I take this example to the extreme. I also feel that this could maybe contradict what we learned from evolution theory. Why would it take so long for a given treat to establish itself. Maybe I mix too much into one bag after reading this one article.
>I also feel that this could maybe contradict what we learned from evolution theory.
It doesn't, but the article doesn't go into this detail, so people unfamiliar with the field wouldn't understand why. The keyword is epigenetics. I.e. how certain genes become activated or deactivated through behaviour and/or environmental influences. But the DNA sequence itself remains unaltered. So no evolution necessary. There are basically a bunch of molecules than sit on top of your DNA that regulate gene expression. They don't just tell a cell to behave like a skin cell or a brain cell, they also regulate the entire cellular metabolism. The discovery that male sperm can also transmit this epigenetic information to offspring is relatively new, but now that we know that, it makes total sense that these gene-expression-modifying behaviours in fathers could affect their children. After all, they simply get to start with a good (or bad) bunch of epigenetic markers. They will not persist across many generations though, so it has no real long term effect on evolution. It may even be an evolved mechanism that allows organisms to respond to environmental changes on timeframes that would be prohibited by evolution.
Not all epigenetics is regulation of gene expression. The article says "these molecules transmit traits to offspring and that they can regulate embryonic development after fertilization" -- that's from the reporter, but I don't have faith that "transmit traits" is at all accurate--it certainly isn't true in the way that genes express traits. And then they quote an actual epigeneticist saying
“We just don’t have really any understanding of how RNAs can do this, and that’s the hand-wavy part”
>that's from the reporter, but I don't have faith that "transmit traits" is at all accurate
It is pretty accurate, even if we don't understand all details yet. Here's a review article of the current research that's not from a popsci journalist: https://www.nature.com/articles/s41467-023-37820-2
> ”They will not persist across many generations though”
Why not? Is there some tempering mechanism on epigenetic transfer? I could imagine that some sperm-conferred epigenetic markers could continue down the male descendants unbroken.
If I understand both correctly, a better answer to your question than sibling post is that yes, that could be imagined, but your dichotomy is not mutually exclusive, and the process described here is much more related to variable conditions of the environment and the parents’ health at the time of conception rather than to the replicable genetic structures.
Speaking mostly from personal experience here, if a kid gets a suped-up liver from their dad's smoking habits, cool. But how many kids fathers stopped smoking when the kid was born? My point, the father's smoking habits may have passed down a strong liver but his continued use damaged the child's lungs and possibly more.
These mechanisms of epigenetic inheritance or whatever need much more study. It is far too early to draw any conclusions other than we need to keep researching.
If true, I suppose there is also a opportunity cost involved. Meaning selecting for better coping with nicotine, does not help selecting for smarter offspring and maybe even preventing that. So it might be somewhat positive but at a cost unknown.
Also there are the very known costs of nicotine damaging sperms, or of course being in literal smoke as a child (or adult) and deal with those real effects.
>Think of all the kids of the 60th and 70th. They must be immune to most toxins ;).
60th and 70th what?? :)
But seriously though, "immune" is a humorous exaggeration, but I'm not sure we have data to rule out the idea that this cohort has increased tolerance to some environmental toxins.
So it's possible the level of harm we see today is already "post-" this protective effect, if any.
I figured, just a joke playing off their typo (hence the smiley).
There were plenty of non-"drug" toxins people were exposed to where levels peaked around that time — leaded gasoline, early food contact plastics with unsafe additives, pesticides that are now banned, etc. But thanks Nancy Reagan. ;)
I certainly didn't; I simply quoted a sentence from the article. (I've noticed that some people have difficulty distinguishing between the person who quotes something and the person being quoted ... it might be a Sally-Anne effect.)
> It’s the rest of the crap in smokes and vapes to be concerned with.
> nicotine is significantly more harmful than caffeine
“Significantly” is an opinion.
It’s more toxic by weight, yes.
Messes with vascular more than caffeine.
Both are an excellent way to screw up heart health.
> let’s not get started on the CFS stuff, treatments for functional disorders are often placebo-resembling.
Personally haven’t needed or wanted to use nicotine, but I have recovered from an array of chronic illnesses; I’ll get started on anything I please, thanks,
especially seeing how many of my peers are hopelessly exhausted and existing on abusive amounts of caffeine/prescription stimulants to get by.
> Both are an excellent way to screw up heart health.
Plain black coffee has, somewhat surprisingly, been repeatedly demonstrated to be very healthy - with substantial reductions in all-cause mortality as well as the chances of developing cardiovascular disease. I tend to live somewhat spartanly in terms of consumption, and wanted to drop my coffee habit which looks something like this [1], but looking up the data on it left me dropping that idea real fast.
does your opinion cover patents who have blood test results showing Lyme, and one or more known coinfections like Bab, Bart, (all known, and treatable bacterial infections),
although it's like milk too. exposure at an early age leads to the body producing more lactase enzyme to digest it. but lack of exposure often makes people lactose intolerant.
So good habits can be good for offspring.
> For instance, mouse fathers exposed to nicotine(opens a new tab) sire male pups with livers that are good at disarming not just nicotine but cocaine and other toxins as well.
So bad habits can be good for offspring.
> “We just don’t have really any understanding of how RNAs can do this, and that’s the hand-wavy part,”
It seems to me to all be the handwavy part. I'm happy to wait until the research is considerably further advanced, past the clickbait stage.