Hey, welcome to Sign Stuff, a production of iHeartRadio Horhea Cham and today we are tackling the science of baldness. Going bald is something that happens to a lot of people. But why do we go bald? Who goes bald? And why does it affect us so much? I'm going to be reviewing the most current theories about the origins of baldness, and I'm going to talk to a couple of experts on two related questions. Why is there a negative stigma
about baldness and is baldness really hereditary? In both cases, I think the answer will surprise you, so comb over with us as we uncover the hairy truth about the science of baldness. Enjoy. Hey, everyone, here are some interesting facts about baldness. According to a recent paper in the prestigious journal Nature Reviews, about fifty percent of men and twenty five percent of women experience some form of balding or hair loss by the time they're fifty years old.
This translates to roughly fifty million men and about thirty million women in the US alone. It also varies a lot with ancestry or race. If you're of South Asian descent, like from India or Pakistan, your chances of losing hair by the time you're fifty jumps to fifty eight percent, whereas if you're of East Asian descent, like from China or Korea, the number drops to twenty five percent. It
also depends a lot on your age. For example, if you're of East Asian descent, your chances of losing hair in your twenties is small, only about two point three percent. In your thirty s it's four percent. In your forties it's eleven percent, although way up to forty seven percent by the time you reach seventy. There are several types
of baldness for men and women. If names like M one or C two, or YOU three or type three, depending on the pattern of hair loss that you get, whether it starts in your forehead or the corners or the top of your scalp. Now, when I started this episode, I wanted to answer the question why do we go bald? But I quickly found out the answer is, we don't know. From an evolutionary perspective, we don't know why this is involved in humans. It's sort of related to your age.
So evolutionary biologists have proposed theories with that in mind. For example, one theory says that it may be assigned to the rest of your tribe that you're older and therefore more mature and wiser, and therefore you should have a position of dominance or leadership. But there are also theories that say that it's as signed to others that you're old and therefore not very good material. Both theories
but explain why baldness helps your species survive. We also don't quite know why baldness happens at the level of hair follicles. We know that when people experience androgenetic alopecia, which is the scientific name for male and female pattern hair loss, the hair follicles in your scalp shrink and become the kind of follicles that cover the non hairy parts of your body, But we don't really know why
this happens. Our current best theory is that it's kind of the opposite of when young men start to grow a beard during puberty. At some point, your hair follicles are just preprogrammed to be more sensitive to your hormones
and change from one kind of hair to another. So when you're a teenager, the hairs on your armpits pubic areas and your chin and upper lip for men, turn into the kind of thick and hairy kind of hair, and at some point, when you get older the hair is on your head do the opposite and turn into the thin, wispy kind. There are hormones that scientists think are involved, like testosterone or diehydrotest ptosterone or DHT, and enzymes that contribute to this, like five alpha reductase type
one and two. We can see that these molecules are more active involving hair follicles, but what sets this process in motion for what is actually happening at the cellular and molecular level is not quite clear. Now, there are some cool things we do know about the genetics of baldness. I'll get to that later in the program with a scientist who's done one of the largest ever genetic population
studies on baldness. But first, there was one section in this Nature Journal paper that caught my attention, and that is a section about how baldness impacts your quality of life. The scientists right, quote androgenetic alopecia can trigger profound negative psychological effects in affected individuals, owing to social pressure to maintain quote good hair end quote. In other words, the
only negative effective bondness are psychological. So to get to the bottom of this, I reached out to a psychologist who's made it his mission to debunk this negative stigma that bondness has in our society and to teach people that bondness, no pun intended, is all in our heads. Well, thank you, doctor Jenkowski for joining us pleasure. Can you please tell us who you are and what do you do?
Yes, I'm doctor Glennankovski. I am a associate professor University College Dublin, and I'm a researcher in psychology who specializes in the social and cultural interpretation of alopecia.
And is that the term we should be using for bondness or are ukay we say bondness or.
Yeah, I'm much more for a further term, boldness as well. I tend to use alopecia in the Ireland because my accent and a lot of Irish people think I'm saying bravery rather than boldness.
Is that true?
Yeah? I say boldness like being bold. Oh, I see, and it's happened so many times now an island that I really I've switched a bit.
Well, there might be another interesting topic for you to research boldness. Yeah, and whether it's related to baldness.
Yes, but you've done a lot.
Of research on this stigma against baldness. Can you tell us what that stigma is?
So there is a tendency for people to have attitudes that are stigmatizing towards men and their boldness in particular. Typically there's experimental studies that show that people hold more negative attitudes towards men with boldness than they do men with full heads of hair.
Okay, can you describe these studies a little bit.
It is actually a large evidence space. So the majority of studies actually tend to be experiments where a group of people are divided randomly into two conditions and presented images of the same man airbrushed, typically with a full head of hair, and then with some boldness. And so it's that say, mimbiture of the man, same facial features, etc. And they are asked to rate the image of the man on certain characteristics like how masculine, how successful, etcetera.
And there's a bias towards certain attributes there.
Is, Yeah, and those tend to be that those men are less attractive, older, that they may be less dominant and some other negative characteristics.
So there is a negative bias that people have about bald men. But here's the thing about those studies. According to doctor Jenkowski, A, people also have a positive bias towards bald men in some categories, and b these negative and positive biases are not that big.
The re such does show that, and I don't mean to minimize it. However, I do question how totalizing that stigma is because there are also some positive attributes that people make about bold men, like that they're more inclined to be leaders, or that they're more affablen approachable than haired men. And then sometimes these differences are also quite small. People can exaggerate how bigly are, especially journalists or businesses, but actually if you look at their data, they're quite small.
New characterized how small they are.
Yeah. So one study found that out of a scale of one hundred of attractiveness, bold men were seven percent less attractive than their head counterpouts and rated on average about two years older than the head counterpart images. So two years older, seven cent less out of one hundred. It's not a huge amount.
No, it's not. I would have thought it was higher, but that seems are most negligible.
I would have thought that too if I wasn't a researcher studying this. Most people think this too, because most of us are influenced by advertising and marketing of anti bold products.
And this brings up the question where does this negative stigma against bog people, or at least the impression that is a big negative stigma against boldners come from. And here doctor Tinkowski has a s pricing theory.
It really does come from anti boldness businesses. They are the ones who profit from this stigma. And we've had a long history of it, and it's ramped up since the nineteen eighties when anti bold products for the first time in history, got more official approval.
Wow, so you're looking it to the business of selling anti partners treatments. It's sort of a timing issue.
Well, we've always had boldness since men have been around. But what we can see in the historical record is that there were many neutral interpretations of boldness. There were some negative and there were also some very positive interpretations. When we see the rise of snake oil products in the eighteen hundreds and the nineteen hundreds, some of them
were for hairy growth. Of course, they weren't effective, but their marketing was designed to show that old men needed these products, needed these treatments for this devastagencies, and if they didn't take it, they might not get a job, they might not get a date, they might not be happy. When they became approved in the eighties and onwards, that gave them scientific legitimacy these products so that doctors and professionals could start to say, these are treatments I see.
Whereas before you might tell your doctor, oh, I think I'm losing my hair, and the doctor might be like, yeah, it's normal, no big deal, nothing's going to happen to you. Now they might be like, oh, there's a treatment for that.
Exactly. Those pharmaceutical companies have done training videos, they've done training programs, They've targeted medical professionals and doctors to convince them that bolding men and bolding people in general need these treatments.
Now, it's hard to say how much of a role the pharmaceutical and Bontner's treatment industries have had in creating this negative stigma against baldness. As I mentioned, there are theories that tie it to our evolutionary history, but it's also hard to discount. For example, remember the Nature Journal paper I've been citing. That paper was written by nine scientists, all of whom have positions at major universities, but at the end of the paper, the journal requires them to
disclose any conflicts of interest. So here's the list of those conflicts of interest for that paper. Authors one two are inventors on patent applications related to hair loss treatment
filed by the University of California, Irvine. Author two is co founder and chief scientific officer at a corporation and has received consultation fees from Audit Labs and lorel Author three has received consultation fees from DS Laboratories, Almirale, thirty Madison, Eli Lilly and Company, Peiser, Iovan Sciences, Bristol Meyers, quibb
Ortho Dermatologics, and Sun Pharmaceutical. Author four has received consultation fees from Eli Lilly and Company, peiser Olaplex, and Maovn Sciences, and they direct the Ethnic Skin program at John Hoppins University, funded by an educational brand from Jansen. Author five has received salary payments from Life and Brain GNBH. Author six has received clinical trial funds from Eli Lilly, and company.
Author seven has received consultation frees from Eli Lillyan Company and has received clinical study funds from Eli Lillien Company, Pfizer, and ATB. Authors eight and nine declare no competing interests. Yeah, that's a lot of conflicts of interest.
All right.
When we come back, we're gonna talk about whether the treatments all these companies are pushing actually work. Do they stop baldness or is it all snake oil. Stay with us, we'll be right back. Welcome back. We're talking about the size of baldness, and so we've talked about what we know and don't know about what causes baldness. Now we're going to talk about the treatments that are out there
for hair loss. In terms of medicines, there's one called monoxidyl, which was originally made to treat hypertension, but then women patients started reporting extra hair growth and so it became a baldanis medicine that you put on the scalp. Scientists have some ideas about what this medicine actually does, but not really. Another class of treatments are five alpha reductase inhibitors,
which includes the popular drug called finasteride. Scientists know these treatments block the enzyme that splits the stosterone called five alpha reductas, but they don't know much beyond that. Now, do these treatments actually work a sort of, according to doctor Jenkowski.
So there are metro analyzes. These are series of studies that look at large pools of data of menking these products versus men who don't take these products, and they're more objective. So these matronalyses have looked many anti baldness products and what they've found is that most produced between eight to twelve hair follow calls in a centimeter squared area of scalp that's monitored, and that's some hairy growth.
It's not nothing, but on average most people have one hundred and twenty hair follow calls and that's centimeter squared area of regrowth.
What doctor Jenkowski seeing is that these treatments do help you grow back on average about eight to ten percent of the hair you lose, which is not nothing, but it's also not a lot.
So most people do not find that to be a cosmetically meaningful amount of hair regrowth. I see these products might be better at preventing further boldness. It's a bit hard to determine that, but in terms of actual hair regrowth is quite minimal.
And of course you have to weigh that against the potential side effects of these treatments.
And obviously the bigger issues which the Metro analyses to show as well, is that some of these products do risk quite severe side of x. You know, if you're taking finasteride, for example, this is a common antibodleness product. Typically it's taken orally and it disrupts your hormonal system, that's how it's working. But there's evidence so it's affecting all sorts of other things that are really important to
your bodily functions, like your mood. Men who've taken a finanasteroid of reported vision problems, reported mood issues, sexual dysfunction issues, these hosts of side effects.
For finasteride fills. The US Food and Drug Administration or FDA, has issued a warning that there is a risk of depression in suicide ideation when using this drug, and according to the Nature paper, there's also a risk of impotence after you start taking the drug.
And what's really difficult for men taking finasteride is you don't which kind of man you're going to be. The one that's going to be negatively somewhat permanently affected by these side effects, or the ones that might have safe experience of it.
Wow, in which case, maybe it's not worth it for those extra eight twelve pollicles exactly. There's also the possibility of hair transplants, which is where they take follicles from one part of your scalp and implant them in the areas where you're losing hair. This treatment is expensive and it's not for everyone. It sort of only works for thinning hair, not full hair loss. So now my question was is this all worth it? What's really the impact
that baldness has in people's lives? Is there any data as to how baldness affects you in life, or in your profession or in your social life?
There is, yeah, Bolting men are surveyed about discrimination romantically and employment socially. What's difficult is that most of these studies are commercially funded and biased, and some of the studies are very very poor, So it might just be a market research a series of questions that are really leading, that are kind of pishing men to suggest they're discriminated against when they're not. Those surveys do show that some men report some discrimination and many men do not report any.
A really important study by Goslin and colleagues in their eighties asked bolding men and haired men what they expected boldness discrimination to be, and then what the actual reality of old discrimination was, and in all cases the reality was much easier than bold men and haired men predict it. So I think those are really useful to put it into perspective for bolding men. We get told that there's huge amounts of discrimination, but actually the reality is that really it's quite rare.
What effect do you think this negative stigma and this commercialization, what does it have on men and people who might be dealing with boldness.
You know, there's a word called medicalization, and it's this term for how normal aspects of our bodies are often changed into diseases, sometimes for commercial profit, and it really changes how we respond to those aspects of our bodies and how we view them. Bold men increasingly see their boldness as a devastating, disadvantageous disease. It's real shame because if you look properly at history and you see so many bolding men of the norm, and that many many
accept it, and that also find positives from it. Shakespeare, for example, said boldness gives you wits. You don't have to listen to the political opinions of barbers. Shakespeare said, there are all these lovely little advantages from it as well. So it's a little bit about having a healthier perspective about it. The loveliest thing for me is that many bold men report a healthier perspective from it, including feeling
less superficial about their own appearance. You know, they accept their bodies and that's great because all of us age and all of our bodies change in different ways and that shouldn't be feared. But also they don't look at other people so superficially. They can also see past appearance, and that's a beautiful thing in a vain world.
Yeah, oh that's interesting. It can change how you see others. Yeah, it is beautiful. It can also help you see.
Beauty, real beauty, which is inner beauty, which is making someone laugh or you know, acts of kindness. It's that kind of beauty that you know, sustains a long term relationship as well. If we're judging people on their head hair follow calls, I don't think that makes a good marriage. I think a good marriage is you know most people realize is beyond the surface.
All right, we talked about the word when and why of boldness. Now we're going to talk about the who who ends up losing their hair is a genetic and if it is, is it something we can predict When we come back, We're going to talk to each geneticis, especially in appearance traits, and who was involved in creating one of the largest and most comprehensive genetic population models, that is the world's or most expert in predicting who will go bald. We'll see what it says about me.
So stay with us and we'll be right back. Hey, welcome back. We're now going to talk to Professor Manfred Kaiser, a molecular biologist at Erasmus University in the Netherlands who specializes in the genetics of appearances. Now this is pretty cool. Imagine that you're at a crime scene and you find some DNA of the person you think might have committed
to crime. What if you could take that DNA and from that genetic code you could tell if the person was tall, or had dark hair or blue eyes, or had a small nose, or was bald or what if you found the DNA of a famous historical person like Genghis Khan or Cleopatra, or the DNA of a distant human ancestor, could you tell from their DNA what they looked like. That is the dream of doctor Kaiser and his colleagues, and to test his idea, they decided to
start with baldness. In twenty twenty two, they published the results of one of the largest genetic population studies ever done on baldness, where they looked at the DNA and the hairline of one hundred and eighty six thousand men of European descent, and then they looked at whether the resulting data could predict who was going to go bald or not. To tell us about what they found, here is Professor Manfred Kaiser. Well, thank you doctor Kaiser for joining us.
Well, you're welcome.
You recently posted the paper on the genetic markers of baldness.
Yeah.
So, baldness, of course is a very remarkable visible trade, especially in men. So we were interested in looking into the predictability. So people do what they call genome white association studies, so they basically scan the genome of one thousands and tens of thousands and hundreds of thousands of which they know, for instance, may it pad on baldness.
So you need these two types of information, and then they ask is there one site in the human genome that is more frequent in people with baldness.
In other words, doctor Kaiser and his team had access to the DNA of one hundred and eighty six thousand men in Europe, for which they knew if they had baldness or not. Then they asked that there was one gene that could predict whether a man was going to be bald or not. And they found two things that are surprising. The first is that there isn't a gene that is going to make you bald. There's hundreds of them.
For male pattern baldness. It seems to be hundreds of genes. All these different genes work together and make what we actually see in the end as made pattern baldness.
Yes, it's not just one gene that makes you go bald, it's hundreds of genes. Wow, so many genes. Why are there so many genes involved in something like hair loss.
Yeah, that's a good question. That's a good question. You have to ask evolution why they made it so complicated. Apparently. You think, oh, so the hair falls out, that is simple, But the reason why a hair may fall out is not simple at all. And of course these genes, they all play different roles in molacular pathways that exist, and that makes the complexity.
I see. It's not a simple process, even though the end result is relatively simple. Indeed, yeah, baldness is complicated. You might have heard that male pattern baldness was due to one gene that is passed down from your mother's side of the family, but this is not quite true. When you look at the genome of hundreds of thousands of men, you see that there are hundreds of genes
that influence the end result of losing your hair. There is one gene in particular that does come from your X chromosome, which is passed down from your mother, that has a higher influence than others, but it's not higher by a lot, according to doctor Kaiser, and there are still hundreds of other genes involved. And doctor Kaiser says this is not unusual. In the human body. Any single thing about the way you look is determined by many
many genes. Your height, your skin color, the shape of your face or nose, whether you have curly or straight hair, studies have found that those are also determined by many many genes. According to doctor Kaiser, there's only one appearance trade that scientists have found is the by a single gene.
So red hair is the only human appearance trait which is actually monogenic, one gene, one trade, but all other appearance traits are influenced by a large number of genes.
That's right, there's a single gene for red hair. If you have it, your hair is red. If you don't have it, your hair is not red. But that's the only gene related to how you look. That's like that.
Well, people thought in the past. Eye color is simple. I mean, there is the notion that brown eye is dominant, and in many cases, if you have one brown eye parent, the child is brown. But not in all cases. And this is not because the father is not the father. This is actually because eye color does have many more than one or two genes. We actually found more than fifty genes for eye color, but there is indeed one
or two that have a larger effect. And therefore, in many situations, if you have one brown eyed parents, you have a brown eyed child, but not in all cases.
All right. The second surprising thing that doctor Kaiser and his colleagues learned about the genetics of bondness was when they tried to use the one hundred genes they found to predict who is going to go bald and who is not. And when you do that, you find that you can't.
And we have done this prediction and tens of thousands of people. Yeah, so it's large data set. So in a prediction studies, people use a term that includes sensitivity and specificity, and you don't have to understand what that term is. You only have to know that this term runs between point five and one. So what we see with these different categories of maypattern baldness is that they run between say point seven and maybe point seventy five.
So it's somewhere in the middle between random prediction and accurate prediction.
What doctor Kaiser is saying is that even if you take these one hundred genes into accounts that we know are associated with baldness, you still can't accurately predict who's going to go bald. Your prediction falls somewhere between a random guess and always being right. So what does that tell you? So it tells you that they predict something, but this is far away from accurate prediction, which also tells you that these hundreds are not enough, and that
tells that people have to find more genes. Doctor Kaiser thinks there may be more than a thousand genes that determine whether you will go bald or not, and to find out what they are we need more data because that difference in accuracy might be hidden in genes that have a low effect on hair loss, which means they are hard to find. Okay, you might be wondering, for hey, what if hair loss is not one hundred percent genetic, wouldn't that explain why it's so hard to predict? And
that is true. There may be some environmental components to baldness, but doctor Kusler says scientists are pretty sure baldness is mostly genetic, and we know this from twin studies. Scientists attract identical twins separated at birth and compare them to twins that grew up together. For the most part, if you're twin who has the same DNA you do is bald, there is a pretty good chance you are bald too. Okay, so what does this all mean and specifically, what does
this all mean for my hair. Okay, so I'm training fifty this.
Year, but you know that's quite good in terms of bolts, I cannot see.
Thank you. So far, so good. So my father still has all his hair. And on my mother's side my grandfather, her father was bald. Oh, and some of my mother's brothers are bald, but some are not. So what does that mean for me? Do you think?
Well? Not so easy indeed. But obviously this one gene that comes from your mother's side, that's only one of one hundreds of thousands, so that per se doesn't tell you much. So if they're fifty percent from your father, give you all the non bold then of course the sum of all the others is larger than the effect of this one gene on the X chromolome. So maybe you will not develop it.
At least that's the hope.
If you would do the genetic tests, you would come up with a fairly low probability.
Okay, I guess my hair loss is TBD to be determined or is it to bald determined. We'll have to check in in a few years to see how good this prediction was. But doctor Casher thinks there's maybe a more important question to ask here.
So the question is why are you doing this? Why do you want to know?
In other words, if someone could predict whether you were going to go bald or not, what are you going to do with that information? We now know it's not going to be possible to perfectly predict baldness. I mean not even red hair can be predicted with one hundred percent accuracy, because our ability to read genes and identify mutations and sequences is never are going to be perfect. So what if a doctor told you you have a fifty percent chance of going bald or an eighty percent chance.
Would that make you start treatments which have serious risks of side effects, or would you wait and see, knowing that starting treatments then might be too late, Or, as doctor Kyser argues, maybe it's better not to know, or maybe we should just accept that there's nothing wrong with being bald.
No indeed, And actually I can tell you that this country, in the Netherlands, I'm not Dutch and Germans. I came here for work, so it's quite fashionable here to shave completely boiled. So I've never seen so many completely shaved persons. It's just fashionable.
Wow. Maybe the real solution Niston moves to the Netherlands. Indeed, all right, there you have it. Maybe the real cure for baldness is for everyone to go Dutch to see it as normal or even beautiful. Thanks for joining us. See you next time you've been listening to Science Stuff. The production of iHeartRadio written and produced by me Or hitch Ham, credited by Rose Seguda, executive producer Jerry Rowland, and audio engineer and mixer Kasey peckram Hey. Thanks to
our experts today. If you're interested, Doctor glenchen Kowski has written a book called Branding Baldness, published by Cambridge University Press that he has pushed to make open access, which means it's free for anyone to download. I also want to thank Professor Luis Garza of John Hopkins University for filling me in on a lot of the details of what we know about baldness. And you can follow me on social media. Just search for PhD Comics and the
name of your favorite platform. Be sure to subscribe to Sign Stuff on the iHeartRadio app, Apple Podcasts or wherever you get your podcasts, and please tell your friends we'll be back next Wednesday with another episode