The Science of Healthy Hair, Hair Loss and How to Regrow Hair
Date: 2023-04-10 | Duration: 02:04:47
Transcript
0:00 Welcome to the Huberman Lab podcast where we discuss science and science-based tools for everyday life. I’m Andrew Huberman, and I’m a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today we are discussing hair. Hair is a topic that occupies the minds of many people. There are people that are losing their hair and want to halt or reverse that loss of hair, and today we will talk about all the ways that science has taught us we can slow or
0:30 even reverse hair loss. I confess that researching today’s topic was a particular joy for me, not because I’m obsessed with hair—mine or the hair of others—but because hair turns out to be fascinating from the perspective of cellular biology and stem cells, which is a topic that I’ve long been interested in and that for much of my career I’ve focused on in the context of development. When your brain and your nervous system develop, it develops from a small batch of cells that turns into billions of cells, and it does that by
1:00 cell replication, something that we call the cell cycle, and we’ll talk a little bit about this and so-called mitosis today. I promise not to get into too much detail, but what makes hair so very interesting from a biological standpoint is that every hair, every single individual strand of hair, has its own little stem cell niche, meaning its own little pocket down there in the follicle in which specific stem cells give rise to those hairs for different durations
1:30 of time depending on the hair, where it is on your body, etc. For instance, the hairs on your head will undergo ongoing growth for four to six or even eight years. Were you to not cut your hair, it would continue to grow—one single hair would continue to grow, all the hairs will continue to grow for up to eight years. That is very different from, for instance, your eyebrows, which have a much shorter period of hair growth, lasting on the order
2:00 of months. That’s why you don’t see people with eyebrows that extend down to their waist, but you can see people with hair on their head that extends down to their waist if they don’t cut it. That discrepancy illustrates for us just how incredible hair follicles and the stem cells that reside within hairs are, and their enormous potential to give rise to these things that we call hairs, which are simply proteins of varying length. Today we are going to address what determines the length of a hair, or rather what determines how long a
2:30 hair continues to grow before it ceases growing and eventually falls out. We’re going to talk about what regulates those stem cells, what allows them to continue to produce hair or cease producing hair, and as we do that, you will learn all the biology in clear, simple terms, regardless of your background, that will really set the stage for understanding what we’ll also talk about, which is how to slow hair loss or halt hair loss entirely or even reverse hair loss. We will talk
3:00 about hormone-related hair loss in both men and women. We will talk about some of the mechanical and stress-related influences on hair loss, and we will talk about the chemical and mechanical approaches to halting and reversing hair loss—everything from minoxidil to dutasteride to ketoconazole to microneedling to thyroid, estrogen, and IGF-1 pathways. Again, all made very clear regardless of whether or not you have a background in biology. I will
3:30 also dispel some of the common myths about balding and hair replacement. If you’ve heard, for instance, that you inherit your patterns of balding from your mother’s father, that is not true, although it is true that you do inherit certain genes that influence whether or not you have a predisposition to balding in particular parts of your head and, believe it or not, even particular parts of your body. But it is not the case that you can simply find a photo of your mother’s father, say at age 50 or age 60
4:00 or 75, and determine whether or not you’ll have the exact same pattern of hair loss. That’s a myth that I’d like to dispel right here and now, and I will dispel some of the other myths about hair loss, hair replacement, and hair regrowth as well. Before we begin, I’d like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero-cost-to-consumer information about science and science-related tools to the general public. In keeping with that theme, I’d like to thank the sponsors of today’s podcast. Our first sponsor is Helix Sleep.
4:30 Helix Sleep makes mattresses and pillows that are of the absolute highest quality. I’ve talked many times before on this podcast about the fact that sleep is the foundation of mental health, physical health, and performance. Helix understands that everybody’s sleep needs are slightly different. If you go to their website, you can take a brief quiz, and that quiz will ask you questions such as: Do you sleep on your back, your side, or your stomach? Maybe you don’t know, which is fine; you can simply answer “I don’t know.” Or, do you tend to run hot or cold during the night? Helix takes those answers and then matches you to a mattress that’s ideal for your sleep
5:00 needs. For me, it matched me to the Dusk mattress, and I’ve been sleeping on a Dusk mattress for over two years now, and my sleep has been better than it ever was previously. If you’re interested in upgrading your mattress, go to helixsleep.com/huberman, take their brief two-minute sleep quiz, and they’ll match you to a customized mattress for you. You’ll also get up to $350 off any mattress order and two free pillows. They have a 10-year warranty, and you get to try out their mattress for 100 nights risk-free. They’ll even pick it up for you if you don’t love the mattress, but I think
5:30 you will; I certainly love mine. Again, if you’re interested, go to helixsleep.com/huberman for up to $350 off and two free pillows. Today’s episode is also brought to us by HVMN Ketone IQ. Ketone IQ is a ketone supplement that increases blood ketones. I want to be very clear that I, like most people, have heard of the ketogenic diet, but I, like most people, do not follow a ketogenic diet—that is, I’m not in ketosis. However, most people don’t realize that you can still benefit from increasing your blood ketones, which is what HVMN Ketone IQ does. I take Ketone
6:00 IQ prior to doing really focused cognitive work. I take it once in the afternoon anytime I’m going to prepare for a podcast or do a podcast, or if I’m going to do some research or focus on a grant—anything that requires a high level of cognitive demand. That’s because ketones are the brain’s preferred use of fuel, even if you’re not following a ketogenic diet. I sometimes also use Ketone IQ prior to workouts, either resistance training workouts or endurance workouts such as running. Again,
6:30 that’s because Ketone IQ, by raising blood ketones, is really a brain fuel. If you’re interested in trying Ketone IQ, go to hvmn.com and use the code HUBERMAN to get 20% off. Again, that’s hvmn.com and use the code HUBERMAN to get 20% off. Today’s episode is also brought to us by ROKA. ROKA makes eyeglasses and sunglasses that were designed with the biology of the visual system in mind. I’ve spent a lifetime working on the biology of the visual system, and I can tell you that your visual system has to contend with an enormous number of challenges for you
7:00 to be able to see clearly throughout the day. For instance, when you go from a shady area to a well-lit area, your brain and eyes have to make a bunch of different adjustments that eyeglasses of the conventional type don’t always compensate for. ROKA eyeglasses and sunglasses compensate for those sorts of changes and all the sorts of changes that your visual system has to contend with, so you always see things with crystal clarity. The company was founded by two All-American swimmers from Stanford, and initially, their eyeglasses and sunglasses were designed for sports performance. Indeed, all of their eyeglasses and sunglasses can be used
7:30 while running or cycling; they won’t slip off your face if you get sweaty. They’re extremely lightweight, but they also have an enormous number of varieties of eyeglasses and sunglasses that are designed to be worn at work or to dinner. They have the classic performance eyeglasses that make you look like a cyborg if you like those; they also have more conventional aesthetics that you’d be comfortable wearing pretty much anywhere. If you’d like to try ROKA eyeglasses or sunglasses, you can go to roka.com and enter the code HUBERMAN to save 20% off your first order. Again, that’s roka.com,
8:00 enter the code HUBERMAN at checkout. Let’s talk about hair. In researching this episode by talking to experts in the biology of hair and the stem cells that exist in all of us that give rise to our hair growth and the pigmentation in our hair, and in talking to experts who understand how to halt and even reverse hair loss, I’ve found that there is a tremendously interesting biology surrounding hair, but there’s also an incredible psychology around hair. In
8:30 fact, most people who experience even marginal hair loss undergo pretty severe anxiety. I confess this is not something I can relate to. I am losing my hair in certain places—I’m 47 years old, I’ve got a couple patches up front where there’s very minimal hair. I think that, as we’ll later learn in this episode, reflects a higher density of DHT (dihydrotestosterone) receptors at that particular location as opposed to elsewhere in my scalp, but keeping my hair is not something that I’ve fretted about
9:00 much of my life. And yet, as I was researching this episode, I remembered an anecdote from my childhood where my father told me—and I think it was because I was stressing about something and I was trying to get to sleep—and he said, “Don’t stress, calm down, and here’s why: if you stress too much, it can actually make your hair fall out. In fact, I have a cousin who lay down one night stressed and woke up the next morning and all of his hair was on his pillow.” I’ll never forget that story. I
9:30 think he was trying to get me to stress less. I don’t know if that story made me stress less or not, but in any event, I don’t know that that story is true. I’m not going to challenge the authenticity of that story—I didn’t have a chance to reach out to my father and ask him to verify or not—but as we’ll soon learn, it is true that our psychological well-being can impact both the coloration, or lack thereof, and the growth rates of our hair. That’s a real thing. And the reverse is also true, which
10:00 is that as hair starts to thin or fall out or change color, many people experience intense anxiety or even depression. This was not something I was really aware of; perhaps that’s just because I’ve always kept my hair pretty short anyway. I always assumed if my hair started to really fall out, I would just shave my head, but that’s me, and that’s not most people out there. I think most people would loathe to lose their hair, and in fact, given the enormous