What's the deal with declining sperm counts?

In our inaugural episode, Emily and Perry talk all things sperm: if it's on the decline, how to juice its quality, the perils of tight underwear, and what a high sperm count says about your manliness (spoiler: absolutely nothing).

Plus, vitamin K shots at birth, the keto diet to treat schizophrenia, and, in honor of the Olympics, whether penis pumping helps your air time.

Submit a question for our weekly mailbag at wellnessactually.fm.

See omnystudio.com/listener for privacy information.

Episode Transcript

Speaker 1 (00:00):
Hey Perry, Hey Emily, So Perry.

Speaker 2 (00:03):
When you were in medical school studying the kidney and
other body parts, did you ever imagine that people would
get so much of their medical information from TikTok?

Speaker 3 (00:14):
No?

Speaker 4 (00:14):
I did not, But of course, full disclosure, TikTok did
not exist when I was in medical school. But no.
Broadly social media was out there, but it was like
people sharing recipes and stuff. It was not how people
got medical information. And it's a completely different world now.
It is an influencer's world and we're just living in it.

Speaker 1 (00:36):
It's a little bleak.

Speaker 4 (00:39):
It is bleak, and you're more social media savvy than
I am, Emily, Like, I'm just sort of getting into
this space and it's very eye opening.

Speaker 2 (00:50):
I think the high for me recently was a whole
social media era in which people were going on to
talk about how if you feed your baby butter, it
makes them sleep through the night, which was such a
great example.

Speaker 1 (01:03):
You probably haven't gotten.

Speaker 4 (01:04):
This, not gotten that one yet. My algorithm is turning
pretty weird, but not that weird.

Speaker 1 (01:10):
And what was interesting about that.

Speaker 2 (01:12):
What's interesting about this whole space is I think it's
so hard for people watching that to know is this
real People will say, oh, evidence says, studies show, but
they don't have any citations because it's TikTok or Instagram
and it's not the New England Journal of Medicine.

Speaker 4 (01:27):
That was one hundred percent as I start, you know,
I was on Instagram and stuff, and my feed before
we started this podcast was like, you know, like improve
your golf swing and you know, here's a great bread recipe.
And then started doing research and all of a sudden,
now my feed is like this wellness influencer style feed,
which I'm sure you're familiar with. And the thing that
stuck with me as I was watching this as someone

(01:49):
who comes from academics, is like, oh, you can just
say shit, like there's no there's no peer review. You
could just say whatever you want. And what I kept
coming back to, especially with things like that that sort
of seem ridiculous, you know, was like, wait, does this
person really believe what they're saying and they're a true

(02:10):
believer in this and they are like a butter advocate,
or do they not believe what they're saying and they're
just saying it for the clicks, or they're grifting and
they want to sell you their butter supplement, and like,
it's really hard to tell the difference, and I don't
even know which one is worse.

Speaker 2 (02:26):
I agree, I mean I think often you know it's
you know, comment supplement for my twelve step routine for
clearer skin, where you know, well, probably they're they're selling
you something. But it's really challenging when people watch this
kind of content to figure out what's real what's not real.
And you know, for me, I always think, even if

(02:48):
they're referencing studies, a lot of times those studies confuse
correlation and causation. You will hear me say that a
million times on this podcast.

Speaker 1 (02:57):
One of my life's.

Speaker 4 (02:58):
Passions, it's going to be on your tune.

Speaker 2 (03:00):
One of my life's passions is the confusion of correlation
and causation, by which I mean that a lot of
times the people who are doing one health behavior are
really different in many other ways. So sure they're taking
a vitamin D supplement, but they're also exercising and not
smoking and doing all kinds of other stuff, and you
don't really know that it's the supplement as opposed to

(03:23):
all the other things.

Speaker 1 (03:24):
And we'll talk about that a lot.

Speaker 4 (03:25):
The type of person who takes the supplement.

Speaker 2 (03:27):
Yeah, I get it, But for me, that's one of
the core confusions, even if we are taking people at
face value and assuming they're not trying to sell me supplements.

Speaker 1 (03:36):
Comment in the comments.

Speaker 4 (03:38):
Is that is why I was so excited when we
decided to do this podcast that we could look at
some of these claims. And actually, you know, you and
I are book people who can read a medical study,
like who know how to go into the literature and
our job figure that's what we do. That's our day jobs, right,
and like figure out what's true, figure out what's not true,
and tell people because you know, some of the stuff

(04:00):
it's not all fake, right, Some of the stuff out
there really can improve your health and some of it can't.
But we're all super busy, and if you don't know
which is which, you're going to like spend twenty nine
hours a day, you know, juggling eight different supplements and
shining red light therapy on your face.

Speaker 2 (04:16):
Absolutely, I think people need to understand both will this
make a difference and how big is that difference? So
I can decide what to spend my very limited amount
of time on.

Speaker 4 (04:26):
And selfishly, I will say that between the two of us.
Even though I'm the medical doctor and you're just whatever
other kind of doctor, you are the healthier one of
the two. So selfishly, I am excited to learn how
to take care of myself even a little bit better.

Speaker 2 (04:41):
I'm going to teach you so much, Perry. Okay, so
this is our first episode.

Speaker 1 (04:46):
What do we have on the menu for today?

Speaker 4 (04:49):
I wish you hadn't phrased it like that, because it's
sperm amazing.

Speaker 1 (04:57):
I'm Emily Astro, I'm an economist and a data x and.

Speaker 4 (05:00):
I'm Harry Wilson, I'm a medical doctor.

Speaker 2 (05:02):
It's Thursday, February twelfth, twenty twenty six, and this is
wellness actually.

Speaker 4 (05:08):
Because you're getting a staggering amount of health and wellness
information nowadays from every source imaginable, and some of it
is awesome and some.

Speaker 1 (05:17):
Of it is well actually bullshit.

Speaker 2 (05:21):
Fortunately, we are both people who know how to read studies,
how to parse the data, and can tell you what's
worth thinking about and what you can safely ignore.

Speaker 4 (05:29):
But before we dig in, a note that this podcast
is for educational purposes and should not be construed as
medical advice. We don't know your unique situation, so talk
to your doctor for personal health decisions.

Speaker 2 (05:40):
This week we're asking what's the deal with declining sperm counts?
And then we'll get to your question of the week,
But first let's do the health news roundup after the break,

(06:01):
all right, Perry, So, last week RFK Junior, the Secretary
of Health and Human Services, claimed that a ketogenic diet.

Speaker 1 (06:08):
Could cure schizophrenia.

Speaker 2 (06:11):
He said the quote is a doctor at Harvard had
cured schizophrenia using the keto diet, which is a high fat,
low carbohydrate diet, and also claim that there were studies
showing that people lose their bipolar diagnosis by changing their diet.
So how much of this is rooted in fact as
opposed to just in nothing?

Speaker 4 (06:32):
So this is really typical of Rfk's style, which is
like there is a kernel of fact in here that
then gets just like expounded to one hundredfold higher, which
you know, is fine if you're maybe an influencer on TikTok,
but is not great if you're the Secretary of Health
and Human Services. So ketogenic diets and what they're talking

(06:52):
about here is not like I'm keto, like you know,
I try to avoid carbs. A medical ketogenic diet is
really hard to do, like it's it's you have special
foods and stuff, you are in the state of ketosis.
And we do use it to prevent seizures in people
who have refractory epilepsy that no drugs work, so it
does affect the brain. There was a small study which

(07:16):
showed a keutogenic diet had modest effects on schizophrenia symptoms
in a subset of people with schizophrenia. The author of
that study was asked about RFK Junior's quote and said themselves, no,
this is not this is not a cure. I mean,
it's clearly not. It's interesting, but this is just, you know,

(07:37):
it speaks to this thing that keeps happening where it's
like your medical problems are kind of your fault. There's
always this subtext that's like, oh, well, if you only
ate a better diet, maybe you wouldn't have schizophrenia, and
it's just it's really like disabling to people with this
kind of condition.

Speaker 2 (07:54):
I think the other piece for me here was this
this sort of taking of what should be the first
step in a kind of research program and deciding that
we're done right the process of science. I mean, you
know this as a researcher, like the process of science
is like, Okay, we do an experiment with like two

(08:15):
people and we see, huh, like maybe there's something interesting there,
and maybe there is something interesting here. But then you
sort of expand it out and think about what would
be feasible, could it work on a larger scale, how
big are the effects? And this is kind of taking
that first step and being like, oh, we're done, we
fixed it, like just eat a lot of bacon or yeah,
And that's not the solution absolutely, And the history of

(08:37):
these interventions across all of medicine is typically that something
that works in a small.

Speaker 4 (08:42):
Group or in lab animals or something's kind of interesting
doesn't scale up, like it doesn't work. The literature is
littered with failed interventions like this. So irresponsible to say,
but let's move on, Emily. Did you see this article
in the New York Times reporting that there has been

(09:02):
an increase in refusals of the vitamin K shot after birth?
So what is going on with vitamin K?

Speaker 3 (09:09):
Now?

Speaker 2 (09:10):
So it's worth saying why we might give kids a
vitamin K shot right after birth, which is that.

Speaker 1 (09:15):
It prevents bleeding.

Speaker 2 (09:17):
So infants who do not have a vitamin K shot
or at a much higher risk for later bleeding, which
can be fatal. And so there are really good reasons
to give infants a vitamin K shot immediately after birth.
It has been done for many decades. It's extremely safe.
But in our current vaccine hes agency environment, this shot,

(09:42):
like many others, has become sort of part of the
kind of we're afraid of shots thing, and more parents
are refusing it, which of course is very dangerous for
their infants.

Speaker 4 (09:52):
But not a vaccine, right, I mean, just let's be clear.

Speaker 1 (09:55):
It's not a vaccine. It's a vitamin shot exactly.

Speaker 2 (09:58):
Yeah, And that's what's I mean, that's sort of a
maz because people are thinking, okay, this is like a vaccine.

Speaker 1 (10:02):
No, it's a vitamin shot. It's a vitamin.

Speaker 4 (10:05):
And yet, right, we like vitamins.

Speaker 2 (10:08):
We like vitamins, I mean the same. What's so interesting is,
of course the same space they love vitamins that are useless.
This is a vitamin that's very helpful, and yet.

Speaker 1 (10:17):
You know, people are refusing it.

Speaker 2 (10:19):
I think it's just an example of where some of
this vaccine hesitancy has spilled over even into things that
are not vaccines and in this case have no side
effects that have very clear obvious beneth.

Speaker 4 (10:32):
Right, there's obviously an element of mistrust of medicine here
that's taking place. There's also this movement towards kind of,
you know, a more natural experience, right, like we didn't,
you know, our ancestors didn't give their kids vitamin K shots.
But I will point out, as I often do, that
things were really way worse in the good old days.
So prior to nineteen hundred, infant mortality was twenty five

(10:54):
percent in the United States, So that's death before age
one one out of every four kids before age five
was about fifty percent. So that is not something we
want to go back to. And the thing that has
changed infant mortality rates so dramatically are interventions like this
kind of you know, straightforward dumb interventions like, oh, babies

(11:15):
are deficient in vitamin K and they have intro you know,
hemorrhage in their brain, and let's give them vitamin K.

Speaker 2 (11:21):
Yeah, so please, if you're having an infant, get at
the vitamin K shot. Okay, So let's turn to a
I would say arguably more important topic than schizophrenia and infants,
which is ski jumping yeah, so it's the Olympics. I
love the Olympics. I like the endurance sports, but I
also like ski jumping, and there's a report of some

(11:45):
mechanical doping in ski jumping which is working like the following.

Speaker 4 (11:49):
Oh, I know where you're going with this.

Speaker 2 (11:50):
Apparently, in ski jumping you want your suit to be
very big because if your suit was like really loose,
it would be like a sale. So before you ski jump,
they take scan of you in your suit to make
sure that the suit is not too far from your body.
So there's a report, it is admittedly from a German tabloid,
that some male ski jumpers are injecting their penis with

(12:12):
acid so their penis will grow, and then the three
D scanner will make it seem like they're filling up
the suit more and so they'll be able to have
a bigger suit. But then the penis goes back down
before the ski jumping, so they get the sale like effect.
I just want to know will this work increase your
penis size and would it have other uses beyond ski
jumping that we should be considering.

Speaker 4 (12:33):
I saw this article too, and yeah, real hard for
me to read. I have to say, I think they
really dropped.

Speaker 1 (12:43):
Because you feel like you caned out on some opportunities.

Speaker 4 (12:47):
You know, I could have been a I could have
been a champion ski jumper. I'll let you draw your
own conclusions. But but no, I mean they missed the
opportunity to call this inflate gate first of all, which
is just journalistic malpractice. I think if these ski jumpers
have the balls to inject their penis, you know, more
power to them. Just to answer the medical side of this,

(13:09):
how uronic acid which is what they're talking about, injecting it, like, yes,
it does swell tissues. I mean so yes, it will
make something bigger transiently. It then gets absorbed by the body.
There's some bodybuilders who have been accused of doing this
and they're you know, pecks and stuff to make them
more swollen. This is a bad idea. You do not
want an infection in your penis or around your penis.

(13:32):
It doesn't turn out well. If you want to never
sleep again, google Fournier's gangreen and you'll you will see
what can happen if you do something like this. So
just you know, fly through the air with your regular penis, please.

Speaker 2 (13:50):
I think that's a good place to stop with our
health news. But after the break we'll come back and
ask what's the deal with declining spurm counts?

Speaker 1 (14:03):
Okay, Perry.

Speaker 2 (14:04):
So if your social media feed is like mine, you
are probably hearing a lot about declining sperm counts in
a very panicked way. So one of the things I
keep hearing is like, if we are going in this direction,
by twenty thirty five, no one will have any sperm.
And I keep thinking about this graphic novel that my

(14:25):
husband liked called Why the Last Man, which is about
a world in which there's just one guy who has
sperm and all the ladies are like chasing him?

Speaker 4 (14:32):
Did you It's classic wish fulfillment graphic novel exactly.

Speaker 2 (14:37):
So I want to talk about whether this concern about
our declining sperm is a real concern or just a
kind of imaginary panic sperm problem like many other things.

Speaker 1 (14:52):
So we're going to talk about that today, But before we.

Speaker 2 (14:54):
Get into it, I think we should make sure everybody
understands what sperm are, where they come from, and how
we would know how many we have and how many
should you have?

Speaker 1 (15:04):
Give me doctor one on one on sperm?

Speaker 4 (15:06):
Okay, all right, Medical school, one on one on sperm.
Here we go. So, sperm are the male unit of
fertilization to carry. A sperm carries half of your genetic information.
The egg has the other half. You combine and you
make a baby. Most people know this. Sperm are produced
in the testes and it's not a simple process. There
are stem cells in the testes that go through multiple

(15:28):
cycles of generation. There's multiple sort of stages of evolution
of sperm, and the testes like some kind of sexual pokemon.
It takes about ninety days between eighty and one hundred
to go from that stem cell to a fully functional
sperm that is ready to go, so to speak. Testes

(15:50):
are busy little guys. They are producing two hundred to
three hundred million sperm cells a day. That's a lot.
That being said, only half are viable in your typical man.
So you know, you produce anything at that rate, you're
going to get some flaws. So only half are going
to be good enough to sort of make it all

(16:10):
the way out. And that's where we get into sperm counts.

Speaker 2 (16:13):
Can I ask when you make sperm that are not used? Obviously,
if you're making three hundred million sperm a day, Is
that right?

Speaker 4 (16:22):
A day? Yeah, they got to go somewhere, right.

Speaker 2 (16:23):
Okay, they got to go somewhere. Like, what happens? Are
you peeing them out? Do they get eaten?

Speaker 1 (16:28):
What happens?

Speaker 4 (16:29):
They kind of get eaten. They just get reabsorbed, So
they don't have an unlimited life span. They'll just kind
of die. And like any dead cell in your body,
once a cell dies and breaks down, these big white
blood cells called macrophages, which are just like big cells
that are specialized in eating dead stuff, come in. They
live in the testes and they eat them up and

(16:50):
they dissolve them and all the nutrients and stuff go
back into your body. So they just get recycled basically. Yeah,
no big all right, no big deal.

Speaker 1 (16:57):
So you have these sperms. Some of them are good,
some of them good.

Speaker 2 (17:00):
When we say that we have good sperm, and I
think this is relevant for talking about declining sperm counts,
because really what we mean is a decline.

Speaker 1 (17:07):
In viable sperm.

Speaker 2 (17:09):
What are the things you need for a sperm to
be capable of fertilization, which is its primary measure of quality.

Speaker 4 (17:17):
Yeah, I mean it's it's a lot more than just
sheer numbers, I think as you're alluding to. Right, So
there's all this social media talk about sperm counts and
declining sperm counts. That's only one parameter in about ten
that urologists, for example, will look at to tell you
what your sperm quality is. So, yes, you need a
certain number. We'll get into what kind of normal numbers
are in just a second. But they have to be

(17:38):
able to move. Sperm swim, so they have to they
have to be motile, they have to move around. You
can see that under a microscope. They have to have
a sort of standard morphology, that tadpole ish thing that
you look at. Some sperm have two heads, some sperm
have two or three tails, and those are not going
to be efficient at getting into an egg. They have
to contain the nuclear payload of half of your genetic material.

(18:01):
If they don't, you're not going to get a viable embryo.
So they have a lot to do, and it's you know,
it's a numbers game basically. In the end, it's a
pretty difficult trek for a sperm to make it all
the way to an egg. It's a hostile environment for
very good reason. The week are weeded out on this

(18:23):
trek to the egg. We were all traumatized as young
children by watching Luk Who's talking where we saw graphic
depictions of sperm competing with each other to get to
the egg. And but that's, you know, that's how biology
is supposed to work. But sperm count is certainly one
part of all this.

Speaker 2 (18:43):
And I also think when we talk when people talk
about declining sperm counts, I think they mean both counts,
but they also often mean some of these other things.
So a decline in sperm that are in decline in
the number of sperm, and decline and the number of
sperm with the right morphology, with the right motility, so
sort of sperm they can have the right shape, they
can swim, they can get to the egg. That's what
where that's what we're focused on. That's what we're what

(19:05):
we're worried.

Speaker 4 (19:05):
About right now. When it comes to count though, because
it's always nice to put like a simple number on things,
there's essentially two counts that get talked about in different studies.
One is actually the sperm concentration, which is the count
per millileter of fluid basically, so how much per mili
leader And then one is the total count. So if
you take all the milli leaders in a particular sample,

(19:28):
how many sperm are in there. Most researchers are focusing
more on that concentration the count per mili leaders as
a better proxy of overall sperm health. And just to
give you some numbers, most men will have you know,
who are healthy and fertile have numbers in the sort
of sixty to one hundred and twenty million range per

(19:52):
milli leader. The who defines any sperm count above sixteen
million per milli leader as normal, they used to say
twenty that's been reduced. And Emily, you're going to tell
me in a second why or if that's for real.
But you know, most most people are actually quite a
bit above that minimum threshold. Nevertheless, lots of panic about

(20:15):
declines in the count over time. So Emily, you tell
me what's the deal with this, Like, what is the
data show? And is it for real?

Speaker 2 (20:23):
I think what's most interesting to me here is why
this is so hard to answer. So if you sort
of think about what you would like to be able
to see to have a measure of sperm counts over time,
Really we would like to sort of take every you know,
person with testicles when they are eighteen, bring them in,
you know, have them jack off into a cup, measure

(20:44):
their sperm, and then we could have if we had
that starting in like nineteen twenty, you know, we could
really get a very good sense of how sperm has
changed over time because you'd have a random sample, or
you have everybody, even just a random sample.

Speaker 1 (20:57):
I would take a random sample.

Speaker 4 (20:58):
Yes, yes, as any economist would. I will point out
that the time of abstinence is an important factor in
sperm counts. So you'd need these eighteen year olds to
hold off on any sort of ejaculation for five days,
which I think is really the hurdle people aren't discussing.
But go ahead, that's the ideal.

Speaker 1 (21:21):
My study is going to totally take care of that.

Speaker 2 (21:23):
I have different ideas, but at any rate, whether I
would be able to do that or not, we have not.
And so most of our numbers about sperm counts come
from selected populations without very good controls. So often we'll
see data from infertile men. Well, that's not very helpful

(21:44):
as a metric over time for a bunch of different reasons. Sure,
so we're kind of working with a lot of pretty
incomplete data, which is why I think the results are
quite vary. So I would say if you look at
meta analyses where they bring together a lot of different
studies of sperm counts over time in a global context,

(22:05):
mostly those suggest some moderate decline in sperm counts over time.
I think the sort of most recent data maybe is
a little more reassuring and suggests maybe it hasn't declined
very much. But I guess my read of the evidence,
I'm curious if you read it differently, is it does
seem like there's some decline, but it's probably not as

(22:27):
extreme as you would take away from some of the
hyperactive claims on the internet.

Speaker 4 (22:35):
Yeah, the sort of catastrophizing of the sperm content. Yeah,
I mean, the one nice meta analysis actually broke down
this issue you're referring to, which is like selection bias
for men who are having fertility problems, right, or couples
that are having fertility problems. So overall, this study found
that the average sperm count in men's sperm concentration in

(22:58):
men from nineteen seventy three to twenty eighteen went from
one hundred million to about fifty million. And that's like, Okay,
all right, So that's you know, almost half, that's pretty solid.

Speaker 2 (23:09):
That's a solid decline, that's a cline, that's a very good,
big decline.

Speaker 4 (23:12):
But when they restricted to the studies that only included
fertile men, so you know, sperm counts for other reason,
the decline was from seventy seven million to seventy two million,
which is like, really not that much. Now, maybe there's
more infertile men, right, Like, it doesn't necessarily mean that
this is just total hocum, but you got to think

(23:34):
through it a little bit more, in a little bit
more detail, right.

Speaker 2 (23:37):
Yeah, And I think that that you know, you're citing
sort of one particular study, and I think one that
got a lot of attention, But there are other meta
analyzes with sort of similar.

Speaker 1 (23:49):
Approaches that to do more.

Speaker 2 (23:52):
Adjustment for say what area you're in or or some
of these fertility metrics which don't actually see sort of
significant or see much much smaller declines. So, you know,
I love data so much. I love numbers and data,
and that in a case like this, I think what's
so hard is because the data is imperfect, it matters

(24:14):
very much what choices you are making about exactly who
you're looking at exactly how you're looking at it, exactly
what you're adjusting for. And so it's not that surprising
that the literature can kind of find everything from there's
no change at all to like, you know, the sperm
counts down by half, and if we keep going on
this trend, you know where we're all doomed forever.

Speaker 4 (24:36):
Well, I'm going to force you to put your nickel
down here. You've read a lot about this. I've read
a lot about this. Yes, data is a little bit
you know, wishy washy here and there, But like heart
of hearts, do you think there's a decline in sperm
counts overall over time?

Speaker 1 (24:49):
I do.

Speaker 2 (24:50):
I mean my read is that there's been a modest
decline in sperm counts over the past fifty years.

Speaker 1 (24:56):
What about you?

Speaker 4 (24:57):
I think that's probably right. That was the vibe I'm
getting to.

Speaker 2 (25:00):
Yeah, I think that there's enough data that points in
that direction. That's an interesting thing about how we sort
of look at data, Like you kind of read enough
of this, and you read it, and you read it,
you sort of get a picture. It's a little hard
to put your finger on. It's not that I'm saying
like I looked at this one study. It's that you
look at all of it together and kind of evaluate, basically,
with the background of being a person who thinks a

(25:21):
lot about evidence, you kind of come out with something.

Speaker 1 (25:24):
So yeah, for me, modest decline. All right, So a very.

Speaker 2 (25:29):
Reasonable follow up question if we both think there's been
some modest decline, is is it relevant?

Speaker 1 (25:34):
Right?

Speaker 2 (25:34):
So, we talked about like the who's got a threshold
of you know, sixteen or twenty. We talk about numbers
like seventy five million per you know, semen unit, you
really only only need one, You only need one Perry. Yes,
So I guess the question is, you know, is this
clinically relevant? Is this the reason we're talking about a

(25:57):
fertility decline in you know, the entire world?

Speaker 4 (26:00):
Like, Okay, a lot to unpack on this, but I'll
start off by saying absolutely not. This is not the
reason for a fertility decline across the world. There are
many more important factors in that, including deliberate choices by
people who are hostly doing meal family planning, and of
course economic conditions that might influence those choices and many

(26:23):
other things. So let's just put that aside. Let's talk physiology.
We actually have pretty good data from in vitro fertilization
studies to know how many sperm it typically takes to
like fertilize an egg. And yes, it only takes one,
but as I said, they're running a gauntlet to get there.
It's very it's very hard. And what these studies show

(26:45):
is sort of a diminishing returns as sperm count increases.
So at the very low end, yes, there's there's less fertility, right,
We're talking less than twenty million per per mili leader.
You know, there's less fertility there. But once you start
getting over that threshold, it really flattens out. There's like
not much of a change in pregnancy rates fertility rates

(27:09):
once you get kind of into the normal range, which
of course leads me to the question, like why are
people so obsessed about this? Like why is it that
your social media feed like God, like I God forbid
searched sperm counts once and now it's just it was
a huge days. It's I need like a I need
a burner account just for this podcast. You know why

(27:32):
the obsession? And I don't want to like armchair psychologists this,
but like is this just a manly thing. Is this
totally like just like a like a tech bro like, yeah.

Speaker 2 (27:43):
Yeah, I for for me. I mean this is a
very interesting question. I think really a question about psychology.
But I think that it is a signal of your
manhood that you have a lot of sperm. Like sperm
is like a like it's a thing you could measure.
And I think particularly for people who'd like to measure stuff,
you know, like I like to feel like you like
to measure HRV, you like to measure your you know,

(28:05):
this hormone and that hormone, and like you want to
measure a sperm count because you want to have the
best you want to have the best sperm.

Speaker 1 (28:12):
But but just.

Speaker 2 (28:13):
Like to have it, you know, not not to do
anything with it, just to have it around for having
and for telling people what it is.

Speaker 4 (28:20):
Yeah, it's like it's like an online IQ test exactly,
or like joining MENSA.

Speaker 2 (28:28):
So what about testosterone? Is testosterone? Are a tesosterone a
sperm count the same? Are they correlated? What do we
see in that?

Speaker 4 (28:35):
Yeah, I've seen a lot of people say like, oh,
sperm count is this proxy for like everything about male health,
including testosterone? Not true? Actually true? With the tiny caveat.
So testosterone levels are correlated with sperm counts in the
first three months of life. So apparently for babies AGC
or the three months, the testosterone level there is important

(28:57):
for proper testicular development. But that's it. Now. You will
see studies that show that men who have very low
sperm counts, like less than twenty million, are more likely
to have low testosterone. So when you have sperm counts
that are low enough to cause a fertility issue, you
are also more likely to have low testosterone. Those things

(29:17):
can be related. But in the normal range of sperm count,
there is no correlation between testosterone and sperm count. So
a sperm count of forty million versus eighty million, those
testosterone levels have no effect on that. And so if
you're using sperm count as a readout of your testosterone,
it's a bad readout, or maybe it's only a readout
of when you are a tiny baby. If you want

(29:38):
to know what your testosterone level is, you can measure
your testosterel test.

Speaker 2 (29:43):
For that one question that I want to come back
to about what you said. So we talked about the.

Speaker 1 (29:49):
Fertility environment being hostile to speram.

Speaker 2 (29:55):
What do you mean, like the vagina eats the sperm
in a negative way.

Speaker 4 (30:00):
Kind of The big issue is acidity.

Speaker 3 (30:03):
So the.

Speaker 4 (30:06):
Vagina, the filopian tubes of these whole areas are are
quite acid. I think the pH I'd have to check,
but it's like four point five or something like that,
which is certainly toxic to sperm. The semen that they
come with is basic, so there's a little acid base
reaction there, like when you do the baking soda and vinegar.

(30:27):
It's less dramatic than that, fortunately, but that's but that's
the primary reason. And and and as I said, it's
like it's for a good reason because there you want
to kind of select for the sperm that is most motile,
most robust, because that's probably the one that has the
best genetic material inside.

Speaker 2 (30:47):
Yeah, so you're really using you're basically using the hostility
as an evolutionary mechanism to kind of find find the
good sperm. Men are just producing just a billion, you know,
so many of these, and we're kind of have a
million different ways that we're trying to get sort of
them out as opposed to taking more time to produce
good ones in the first place, which doesn't seem to
be the approach that we've taken.

Speaker 4 (31:06):
You got it, So let's go through. Now. Okay, so
we're going to take it on a little bit of faith.
But some data that that sperm counts really are declining.
We both think that this is happening, And of course
then the next question is why. And even before we
get to some of the like really rigorous studies on this,
I think we need to address just a handful of

(31:28):
the things that I have heard on social media about this.
Let me start with a clip from the Hubreman podcast
about this issue.

Speaker 3 (31:39):
You might have heard that carrying your phone in your
pocket can reduce your testosterone levels and sperm count. And
guess what that is true? The data contained within this
meta analysis and other MEDA analyzes clearly point out that
it can reduce sperm count and maybe testosterone levels significantly,
but certainly sperm count and motility significantly. It reduces sperm quality.

(32:00):
So should you avoid putting your phone in your pocket,
certainly your front pocket, I would suggest yes, right if
you are somebody who is seeking to conceive.

Speaker 4 (32:09):
Emily, Before I get your response to that, I just
want to say that that was one of the most
epic eye rolls. I have ever seen your opinion.

Speaker 2 (32:19):
I do not think we have good evidence that cell
phones reduced sperm counts. You know, we have a little
bit of like confounded evidence that people who talk of
the phone war maybe have lower sperm counts, but of
course that's not a piece of causal evidence. There's this
idea you often hear about, like when you have your

(32:39):
cell phone in your in your pocket, it reduces your
sperm count. But again we sort of look at the
better evidence on that, where they know where people are
carrying their phones and so on, just don't see any
impact on sperm count. There's also no reason to think
that your cell phone waves would impact your There's no
reason for that.

Speaker 4 (32:55):
Yeah, yeah, there's no biologic plausibility, something we biologility always
always talk about. You want, at the very least the
sort of floor the table stakes are. There has to
be like a reason to believe this would be true,
and then you need to look for evidence that actually
is true. And I agree, I don't know why, but
this is all over the place. I actually saw a

(33:16):
clip of a woman responding I like to this Huberman clip,
and it was like it was like reacting to the
Huberman clip, and I was like, oh, this is going
to be one of my people who's going to be like,
what the hell's you talking about? And it was a
woman being like, good job, Andrew Huberman and also, don't
put your cell phone in a fanny pack if you're
a woman, because that can affect your eggs. And I'm like, oh, man,

(33:37):
like now we can't even use fanny packs, and they.

Speaker 1 (33:40):
Were coming back.

Speaker 2 (33:41):
I mean, I think that this is an example where
people are pulling causality of time trends, where it's sort
of easy to say, oh, look, you know, we think
sperm counts have gone down over time. Cell phones have
gone up over time, and so you know, those two
things move together. Of course, many things have gone up
over time, not just cell phones. And so the idea
that two trends that moved in the same direction is

(34:01):
not a way that we generate causality. Ever, Yeah, terrible,
terrible way to do causality.

Speaker 4 (34:06):
My Nickel down here that the actual reason for declining
sperm counts is the rise in political violence. What about okay,
what about laptops on laps because okay, here we got
some biological plausibility. Laptops are warm. You know, the reason
that the testes are outside of the bodies because sperm

(34:28):
development is inhibited at ninety eight point six degrees at
body temperature, they have to be slightly cooler than that.
I saw a nice study looking at like the measured
scrotal temperatures. This is in a lap, so measuring scrotal
temperatures of people with a laptop on their lap, and
it found about two and a half to three degrees

(34:49):
celsius higher with the laptop on their lap, And like, okay,
so more biologically plausible. What do you think about laptops?

Speaker 2 (34:58):
Yeah, so I think it's actually is pretty I want
to put a pin on the heat thing, because actually
one of the things that does reliably impede sperm production
is having your testicles be very hot. And there are
other things more important than laptops for that, like very
tight underwear. So like heat is an important consideration here.

(35:21):
The laptop explanation, My guess is it's like it is
biologically plausible. My guess is it's not very important just
in terms of total magnitude, partly because I don't actually
think people have their laptops on their laps like that much,
and those effect sizes are not that big, and I
would be surprised if this explained much of a time trend.

Speaker 1 (35:45):
But I would say, like, from.

Speaker 2 (35:46):
An individual standpoint, if you are worried about your sperm count,
if you're trying to get pregnant, if you're worried about
your fertility, you're thinking about your sperm count, and you're
carrying your laptop on your lap all the time, maybe
don't do that.

Speaker 1 (35:56):
Put it on a table.

Speaker 2 (35:57):
Yeah, all right, so we got we're we're going to
carry our cell phone, but we're not going to put
our laptop.

Speaker 1 (36:02):
What about pesticides? Toxins?

Speaker 4 (36:06):
Okay, toxins. So you know, this is interesting because toxins
is such a huge term. It's such a huge umbrella,
and it can range from everything from like yeah, the
stuff we sparan crops to like automobile exhaust and particulate matter,
and depending on who you ask, like corn stuff like yeah,

(36:28):
atizes right, like all this stuff, and so it's so
difficult to pin down exactly what's happening. I will say
that there is some interesting data and pesticides, I'm not
quite ready to like pooh pooh this entirely. So the
one that people will have probably heard of. Most is

(36:50):
called atrazine. And the reason you see a lot about
this is because this was the pesticide that in like
a lab and animal or like in a frog embryo study,
was able to change the gender of the frogs. Right,
this is like the pesticides are turning frogs gay type
of things. So like a lot of hype, I think

(37:12):
a lot of misunderstanding of what these studies actually looked at.
But some of these pesticides do have hormonal activity, like
can be hormonally disruptive, changing levels of estrogen and testosterone
in animals at least and potentially humans. There was a
small ish case control study looking at infertility, So I'm

(37:38):
moving away from sperm counts here. I'm I'm just talking
about infertility. Fifty men who were infertile, fifty men who
weren't infertile, where the levels of pesticides were measured in
their blood and there was a signal that the men
who were infertile were more likely to have higher levels
of pesticides in their blood. Now, like, does that mean
it's the pesticides? Does it mean they tend to eat

(38:00):
that contain more pesticides? Are like they don't wash their
foods off with pesticides. We have no idea. But in
contrast to cell phones, which always feels like a little
like wishy washy woo science to me, you know, pesticides
are chemicals. They kill bugs, they may do something to us.

Speaker 2 (38:16):
Right, So let me just say I hear you on
the biological plausibility. I find the study you just described
to be ridiculous. It is a kind of study I
hate called a case control study. And in a study
like this, I'm sorry, I'm going to nerd out for people.
But what we're doing is we're sort of taking people

(38:36):
who have some condition and then in this case, infertility,
and then finding some other people who don't have the
condition and then asking them.

Speaker 1 (38:42):
We're looking at, you.

Speaker 2 (38:43):
Know, different exposures, look different at different features of these people.
And the problem with the study like that is twofold one.
There are many other potential differences across people, so you know,
it's definitely not randomized, and if you look at those
two groups are going to be different all all kinds
of other things, not just pesticides, And so we're potentially

(39:05):
confusing correlation between pesticide exposure and infertility with causality, no
reason to think it's causal. The second thing is, in
that particular kind of study, you also have a problem
because you're selecting the people totally differently, and so that
makes your kind of correlation problem worse. So I hear

(39:25):
you on the biological plausibility. I think case control studies
are so deeply stupid. It's like one of my just
total pet peeves that anyone ever uses them.

Speaker 4 (39:35):
Sorry, I'm quickly going to search my Google scholar record
for all case control studies that I may or may
not have aged totally.

Speaker 2 (39:48):
That's the gold standard, and it probably doesn't show this, Okay.
So I mean, look, it's very difficult with something like toxins.

Speaker 1 (39:54):
I think in the end it's going.

Speaker 2 (39:54):
To be very difficult to say, well, it's not taught
like because that means kind of anything.

Speaker 1 (40:00):
But I would be surprised.

Speaker 4 (40:02):
It also perpetuates the sort of like decline of civilization
narrative that I think goes along with the sperm count decline. Right,
It's like there's this weird overlap almost from you know,
like everything is getting worse, right, the sperm counts are
going down and the pesticides are going up, and you know,
of course the data dogs are gay, right, So I

(40:25):
think we are. We are definitely in that sort of
time period, and it's going to be hard to disabuse
people of any notions like that.

Speaker 2 (40:32):
All right, So what about last thing I think we
hear about is soy so so for your sperm.

Speaker 4 (40:39):
So if your sperm count is like the true measure
of your masculinity, and the like opposite of that is
how much soy you drink?

Speaker 1 (40:47):
Totally okay.

Speaker 4 (40:51):
So the reason people even talk about this, the soy
boy phenomenon, right, the reason people even talk about this
is because soy, like many plants, contains chemicals which are
called phyto estrogens, which just means plant estrogens something like that.
These are chemical compounds that have a similar chemical structure

(41:14):
to human estrogen, and in some extraordinary cases, in very
high doses, can mimic some of the effects of human estrogen.
You can see, I'm qualifying this quite a lot. That
is that's it, right, Like, that's all that's based on,
is like there's a little molecule in soy and lots

(41:34):
of other plants, by the way, that like looks you know,
if you squint, kind of like the same chemical structure
as estrogen. There is no good data to suggest that
soy intake has any effect on sperm count whatsoever, really none.
In fact, there's there's quite good data that shows that
it has no effect whatsoever. There's even emily randomized trial
data where they took men and randomized them to have

(41:58):
like a high SOI diet versus not a high soy
diet and measured their sperm counts and there was still
no difference. So it's not soy.

Speaker 1 (42:06):
It's not soy, it's not soil. Okay, So it's not
any of these things. I think we should talk about
what it is.

Speaker 2 (42:15):
Yeah, potentially like what might be responsible for this change?
And to do that we basically like for something to
explain this trend, it needs to both impact sperm count
and be trending over time, and I actually think those
are like a sort of both pretty important. So there
are some things that are that do affect your sperm

(42:37):
count but are not trending over time, and then things
that are trending over time, which we've talked about many
that don't affet sperm size.

Speaker 1 (42:44):
You kind of need something to intersect to matter there.

Speaker 4 (42:48):
Yeah, So what is it? Well? All right, let me
let me go for low hanging fruit. You mentioned earlier
one when we were talking about laptops that he is
a major consideration here, So talk to me about heat.
What's going on there?

Speaker 2 (43:02):
Yeah, So I think heat is very important because it
is one of the pieces here where when I talk
to people about sort of infertility and about male factor,
infertility is actually something not everybody thinks about and is
potentially quite important. So, as we mentioned, your testicles need
to be slightly cooler than body temperature in order to
efficiently produce sperm, which means if they're very hot, either

(43:26):
because you're making them hot with some external source like
a sauna or a hot tub frequently, or if they're
too close to your body, that can reduce spermcat And actually,
like one of my favorite studies of this is one
in which researchers took men and they gave them these
like super tight underwear, So you know, they had them
wear super tight underwear all the time for several months,

(43:49):
and you can actually see this for science, and you
can actually see this sperm count go to zero.

Speaker 1 (43:55):
So there's sperm count. There's sort of a like effective
sperm count.

Speaker 2 (43:58):
Basically goes to zero and then comes back up after
they take off the underwear. So you know, this is
a great system for birth control that I think we're underutilizing.
But also it really illustrates like this actually potentially quite
quite important. And so this can apply, you know to
again tight underwear, not clinically study tight, but just in general,

(44:21):
tighter underwear may lower.

Speaker 1 (44:23):
Your sperm count.

Speaker 2 (44:24):
People who are doing like a lot of like cycling,
you know, not like I ride my bike to work,
you know, every day kind of cycling, but like you're
in the cycling peloton wearing the tight bike shorts on
your bike for nine hours a day.

Speaker 1 (44:38):
That's not gonna be good. It's like, be good for
your sperm.

Speaker 2 (44:41):
So heat is a I think actually heat is a
big factor. I don't think it is likely that it
is a factor that explains much of the trend over time,
because I'm not sure why people's testicles would be hotter
now than they were.

Speaker 4 (44:52):
This isn't a global warming argument that you're making, Not.

Speaker 1 (44:54):
A global warming argument.

Speaker 2 (44:55):
This is just like, this is an individual actionable thing.
And I will say there's two other kind of individual
actionable things which I also don't think are anything about
the trends, which are heavy alcohol consumption and smoking. So
both consumption of alcohol at a very high rate and
cigarette smoking definitely affect sperm counts and sperm quality. But

(45:17):
those two things have both declined over time globally, so
unlikely to explain trends in sperm counts, even if they
are potentially important changes for some individual looking to improve
their sperm So we got to look for something else.

Speaker 4 (45:30):
So we need to look for something that affects sperm
count and has been rising since the seventies.

Speaker 1 (45:37):
And what do you think it is?

Speaker 4 (45:39):
I will tell you. As I was digging into the
medical literature, scientific literature on this, thinking that there would
be more controversy just based on what I saw on
social media, I was like, oh, there are eight million
studies that show that higher BMIs associated with lower sperm count.
Obesity is nearly a major factor in sperm counts. It

(46:03):
was like not subtle. It wasn't one of those situations
where it's like, oh, well, this study says this, and
this study says that it's like a consistent finding. Did
you find the same thing? And like, why why isn't
this just like the obvious answer?

Speaker 1 (46:14):
I found exactly the same thing.

Speaker 2 (46:16):
I actually would take it one step further, which is
you can see both the impacts of obesity on sperm counts,
and you can see on the flip side with weight loss,
and particularly with GLP ones, you can actually see men
who go on to GLP one sperm parameters improve, sperm counts,
improve sperm mobility improves as.

Speaker 1 (46:34):
A result presumably of weight loss.

Speaker 2 (46:37):
And so this, to me, this jumped out very obviously
as a clear explanation something we know has trended up
over time, something that's very clearly associated with sperm counts.
And it kind of left me, as I'm often in
these situations, being like, Okay, given that the decline in
spermcout's not very big, this probably explains almost all of

(46:58):
what we have seen when we go into these like
cell phones and this and that and soy and all
this other stuff. There's like an obvious explanation staring you
in the face that almost certainly explains like ninety five
percent of anything that we're seeing.

Speaker 1 (47:12):
Yeah, ended up being kind of it was like a little.

Speaker 4 (47:14):
Right, right right. It's anticlimactic, and maybe that's why you
don't see it on social media as much as you
should because you know, it's more it's it's it's more
interesting to say, oh, it's this thing you haven't thought of, right,
Like you didn't realize that fluorescent lights are you know,
talking to your supermatosites in some weird way.

Speaker 1 (47:32):
Yeah.

Speaker 2 (47:32):
I also think people are looking for solutions. If you
sort of if this is something you're worried about, you're
looking for a solution. Potentially it's sort of interesting or
different or like you know, and things.

Speaker 1 (47:43):
Get clicks the solution.

Speaker 2 (47:44):
That's like people, you know, obesity is a metab issue
that we should be addressing in our health choices. That
is something people have been hearing for all kinds of reasons,
not just for this reason. And so just this is
like yet another reason and it's just like that's boring,
like just another like shamey, well you lose weight. It's like, yeah,
hear that, We hear that all the time already.

Speaker 1 (48:06):
Yeah.

Speaker 2 (48:07):
So we talked before about biological plausibility in this explanation
about obesity, is this biologically plausible explanation?

Speaker 4 (48:15):
And why it is definitely biologically plausible, although like all things,
it's complicated. So fat is a hormonally active organ, so
so the more body fat, there is the more levels
of certain hormones, including estrogen like hormones even in men
get generated by fat tissue. And so there's this sort

(48:38):
of endocrine phenomenon that will happen with overweight and obesity
that could affect sperm production. But like that has not
been totally well elucidated. There may well be other reasons,
whether it's like glucose metabolism and things like that which
might be important for keeping sperm alive longer and stuff
like that. Whether it's vascular you know, there needs to

(48:59):
be a quit blood flow and things that all remains
to be seen. But we talk emily a lot about
correlation versus causation. We kind of throw that out, but
I just to get metaphysical for a second. I think
the way I define this for like my students people say, oh,
you know A causes B, that's important to know. The

(49:20):
reason we care if A causes B or if it
is just associated with B is because if A causes B,
then changing A changes B. And that's where the rubber
meets the road in terms of health. Right. And so
what you pointed out was like if obesity overweight causes
low sperm counts, then changing your weight will increase your

(49:42):
sperm counts, and that is the level of evidence we
have from the GLP one trials. So that's like, you know,
I'm sure a philosopher would take issue with that particular
definition of causality, but as a doctor, like, that's all
I care about, Like can I change this and make
you better? Yes? Great?

Speaker 1 (49:57):
Yeah, yeah.

Speaker 2 (49:57):
I think when we think about causality as economists also
are actually much more focused on the idea of if
I change this, well this other thing change, as opposed
to exactly why right, So I sort of asked you about.

Speaker 1 (50:09):
Like what is the mechanism for this? But in practice, you.

Speaker 2 (50:12):
Know, one of the things we get out of that
GLP one evidence is if we change this, then sperm
count would change, and that's the.

Speaker 1 (50:19):
Behaviorally relevant thing.

Speaker 2 (50:20):
It is interesting to think about, well, why, you know,
what would be the mechanism there, partly because it might suggest,
you know, variations on the behavior change, or it just
might help us understand people better. But causality is really
about if I change X, would Y change?

Speaker 1 (50:37):
And that is very different.

Speaker 2 (50:38):
From when we talk about correlation, and we just see
like these two things are moving together, which could be
because X causes why.

Speaker 1 (50:45):
Could because of why causes X. It could because some.

Speaker 2 (50:47):
Other things Z causes X and causes why. And that's
that's not super helpful. That's not super helpful for a decision.

Speaker 4 (50:55):
So I want to drill down. Now, we've talked about
the population. We've talked about millions of people and the
average sperm count and stuff like that. We've said, how,
you know, a lowish sperm count at a very low
end kind of impact fertility, but beyond the very low
end doesn't seem to matter too much. But let's take
an individual like I would probably argue if a patient

(51:16):
came to me and said, you know, my sperm count
is sixty million, I'd like to get it up to
one hundred million. I think my answer would be, like,
why you're not having fertility issues? Like, sperm count doesn't
correlate with you know, how strong you are, how fast
you can run a mile, like how good you are
in bed, Like, none of these things correlate. Nevertheless, people

(51:37):
seem to care. So what is your sort of set
of recommendations for like, like, let's do that thing where
you say, oh, get your sperm count up for some reason.

Speaker 2 (51:45):
Yeah, So First of all, I think there are a
set of people who would care if you are trying
to get purent and maybe not to go from sixty
to one hundred. But I actually think we're probably in
some sets of populations undertesting people sperm. I think when
couples go to try to get pregnant, they often, like women, do.

Speaker 1 (52:00):
A fertility work up.

Speaker 2 (52:01):
I actually think it's a lot of value in men
doing some fertility work up to.

Speaker 1 (52:05):
Begin with, partly because this is movable right in ways.

Speaker 2 (52:08):
I will say, so, if you come you do a
sperm workup and you find your sperm count is, you know,
twenty million, there may well be things you can do
to raise it, which would be and this because it
is not too complicated. You know, don't drink heavily, So
if you're doing a lot of binge drinking, try to
cut down. If you are smoking a lot of tobacco
or cannabis, try to cut down or quit altogether. If

(52:31):
you are doing a lot of activities that keep your
testicles very hot, like regular sauna, the most common thing
would be people doing like regular sauna or hot tub usage,
try to take a break from doing those. And the
fourth one is you know, if people are struggling with obesity,
I think a GLP one is worth thinking about in
that situation. But again, I would recommend these things for

(52:54):
someone who was trying to use their sperm for pregnancy.

Speaker 1 (52:57):
Right if you said I'm hoping to use sperm.

Speaker 2 (53:00):
Pretty soon to you know, get into somebody's egg, that's
kind of when you want to be thinking about this.

Speaker 1 (53:06):
You shouldn't.

Speaker 2 (53:07):
This isn't just like you know, for fun. I mean
it could, but like it's it's not a point if
you're not using it.

Speaker 4 (53:14):
I just to drive that point home. And I'm going
to geek out a little bit here now and talk
about this thing called the coefficient of variation. When you
measure something, there's a question you have to ask, which is,
if I measure this again at some time in the future,
well I get the same result. And how much that

(53:34):
changes from one measurement to another can be statistically defined
as this thing called the coefficient of variation. A typical
lab test like you might get in the hospital, like
your hemoglobin test, has a coefficient a variation of about
four percent, which means that if I measure you today
and I measure you tomorrow, on average, there'll be about
four percent different, you know, kind of bounces around just

(53:54):
a little bit, No big deal. There are few tests
with a higher coefficient variation sperm count. It's about fifty percent.
So I just want people to on the individual level, right,
So if you measure me today and even all like
taking care of all the variables, right, like remaining abstinent
for five days whatever, fifty percent difference on average between

(54:15):
test and retest. So everyone needs to keep in mind
when they see those people on social media who are like,
my sperm count was forty million and then I'd like,
you know, eight keenwa for eight meals a day, and
then it went up to seventy million, Like, that's within
the range of expected variability. So the decline of sperm
count is a population wide phenomenon, like it can be

(54:37):
real on a population for an individual. It's actually recommended
in fertility testing that men get tested multiple times because
of this issue because there's so much variability. And certainly
if you're just using it as like I want to
put this on my Tinder bio or whatever, well you
should test a bunch of times and take the average.

Speaker 2 (54:56):
It's like retaking the essay because they only caught the
highest one.

Speaker 1 (55:00):
So just keep testing and testing until you get a
number that you like. Put that your tender bio, and
then you're done. I'd say good.

Speaker 2 (55:06):
Luck with that, all right, Perry, what's your one thing
on sperm Uh.

Speaker 4 (55:11):
Here's my one thing. Here's my hot take. There's no
reason to care about your sperm count if you're not
trying to get someone pregnant, full stop.

Speaker 1 (55:19):
My one thing is keep your balls cool.

Speaker 4 (55:22):
Keep it cool, keep it cool. That's it for sperm counts.
We'll get to your listener questions after the break. We've
got a great question here from Anna in Columbus, Ohio.

Speaker 1 (55:39):
Hi, Emily and Perry. I'm excited for this podcast, and
I have a fun question for you. Is there anything
health related.

Speaker 2 (55:45):
That you do that isn't supported by data but you
just do it out of habit or for juju like
the rest of us.

Speaker 1 (55:52):
Thank you.

Speaker 4 (55:53):
I do have a belief that blueberries are way healthier
than people think they are, and I have never looked
it up and they just taste healthy to me. But
maybe I'm right. Maybe if we do a dig into that,
it does have data to support.

Speaker 1 (56:08):
It, like healthier than other fruits.

Speaker 4 (56:11):
They're the healthiest tasting food. That's so all right.

Speaker 1 (56:19):
Can't you just say you like blueberries?

Speaker 4 (56:21):
I don't. I mean, I like other things more than blueberries,
but they the taste of health to me is somewhat
tart blueberry, I think, But I have no data to
support that they're particularly healthy.

Speaker 2 (56:33):
Wow, I cannot think of a single This is so
I feel like such a jerk.

Speaker 1 (56:39):
I can't.

Speaker 2 (56:40):
I do all kinds of weird stuff, but I feel
that all of it could be supported by data.

Speaker 4 (56:47):
That's the problem with this question is that you probably
can find that you like, you could find data to
support anything, Like I can find you a study that
shows the blueberries to reduce the risk of cancer, right,
like totally.

Speaker 1 (56:58):
Oh, I'll tell you what I do.

Speaker 2 (56:59):
I hold a very strong superstition about I am extremely
neurotic about which shoes I wear at which times for
when I run. And I have like very strong feelings
like this is a shoe that you have to use
when you're running easy, This is a shoe when you
use for this kind of run. This is a shoe
and some of them are literally the same shoes, but
like one of them is an older version, Like I've
run on them more so they've gotten like downgraded to

(57:21):
like the medium long run from the And I think
that if you open the cabinets in my family room
where I.

Speaker 1 (57:28):
Keep the shoes, you would be disturbed.

Speaker 4 (57:32):
Okay, we will be sure to post a picture of
Emily's weird shoe closet. Stick with us next week when
we will ask what's the deal with peptides?

Speaker 2 (57:42):
Wellness Actually is produced in association with iHeartMedia. Our senior
producer is Tamar Avishai. Our executive producer is Jennifer Bassett.
Our theme music is by Eric Deutsch, and our content
is for educational purposes only.

Speaker 4 (57:55):
If you like the show, help other people find us.
Leave a rating and review on Apple Podcasts or your
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the show. Don't give the TikTokers all the power, and
don't forget we want to hear from you. Head over
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for our mailbag or suggest a topic for a future show.

Speaker 1 (58:15):
We'll let the influencers have the last word.

Speaker 4 (58:18):
Sperm counts have drop more than fifty percent in the
last fifty years. If this keeps up, natural conceptions going
to be as rare as a Cleveland Brown Super Bowl parade.
Your grandkids might need a lab just to exist.