5 Things Your Hair Can Tell You About Your Health
Your hair isn't just something you have to deal with every morning, it's a part of who you are, and there are things it can tell you about your personal health.
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General hair loss:
Patchy hair loss:
Unusual hair growth:
Thicker hair growth:


  • rainynight02

    Bio-sex females there's a stupid word again what female is not biologically female?

  • Liusila

    7:30 wtf is this. I have tiny transparent hair pretty much everywhere. I’m not anorexic!

  • Liusila

    I’ve had dandruff and an itchy spot on my head. It really doesn’t respond to any shampoo and I know it’s part of a bigger thing because when it gets worse a few other areas around my body get really dry and start to itch. Wtf.

  • The Friendly Atheist
    The Friendly Atheist

    I started going bald at 16 or so

  • ღ Ashimari ღ
    ღ Ashimari ღ

    I leave the floor coated in hair wherever I go but I have a super thick coat of hair, even with shoulder length, it takes a ton for it to dry It's been months like this and no notorious change, but as the video says, probably has to do with Ballet hahah

  • MsMcmoe

    Hmm, didn't hear it mentioned that a persons' thyroid may be out of balance, or there's a nutritional/vitamin deficiency .

  • Yo Soybean
    Yo Soybean

    My mom has alopecia, and she has no hair at all. I was wondering, is it genetic?

  • limpnjen

    That first picture of the baby head made my skin crawl.

  • Mr Niceguy
    Mr Niceguy

    The title doesn't fit to the content. Should be... "5 (interesting) hair conditions"

  • Maurice Spence
    Maurice Spence

    I noticed I had alopecia areata after a visit to the barbershop. I thought I was aging way fast or something

  • Rachel Holt
    Rachel Holt

    Shedding more frequently can also be caused by thyroid imbalances

  • Morris Chen
    Morris Chen

    Thank you for using trans/gender-inclusive language!! This just made me love you and your channel even more (which I didn't know was possible)

  • Mathew Subritzky
    Mathew Subritzky

    hair loss can be a result of spinning on your head.

  • Lucia Jayne
    Lucia Jayne

    @sciShow ... about personal health ... what about a video in oil pulling. Is there science behind it?

  • Michael P.
    Michael P.

    Going through the ninth month of tellogen effluvium, the hair has still not recovered. I've learned my lesson with stress.

  • Letolz Velostoll
    Letolz Velostoll

    "menopause can affect someone's..." you can tell "menopause can affect a woman's..." is being avoided, because men can undergo menopause now.

  • Nightshade Kelly
    Nightshade Kelly

    Why does hair grow long on your head but not your arms and legs

  • Nightshade Kelly
    Nightshade Kelly

    Im 16 and have gray hair

    • Lio Jio
      Lio Jio

      more like 61

  • Nightshade Kelly
    Nightshade Kelly

    If goku or vegetas hair fell out it would be a nightmare

  • Professsor

    My scalp is itchy...

  • Elly Arrow
    Elly Arrow

    Omg, bio female... as in opposed to what... artifical females?? O.O

  • -

    One time I suddenly developed alopecia barbae which caused a small, circular bald spot in my beard (which was still visible even after shaving because it was completely hairless) and it was caused by stress and went away after a while.

  • chad x
    chad x

    Right. So leave it to your incompetent doctor.

  • Hypatia Ravenclaw Sklodowska
    Hypatia Ravenclaw Sklodowska

    "your hair isn't just something that you have to deal with every morning" - first time someone accurately described hair imo

  • Rug46

    Where are my fellow red hair bois :P

  • Luka Cvitkovic
    Luka Cvitkovic

    Ah yes, seborrheic dermatitis, a simple spell, but quite unbreakable

  • DaBlondDude

    Nice disclaimer lol, though kinda sad it's needed

  • Nishant Sengar
    Nishant Sengar

    Nicely explained, but what causes premature greying of hair, can that be treated? I have seen even the 5 years old kids start to have grey hair.. is it all diet dependent?

    • Nishant Sengar
      Nishant Sengar

      @gingergamergirl98 I thinks it's more to do with your diet, especially if it lacks vitamin b6, b12 and D..

    • gingergamergirl98

      Nishant Sengar AFAIK it’s genetic

  • Jeremy Pickett
    Jeremy Pickett

    Too many comments way funnier than me :) Thank you Sci, this happens to the best of us and shouldn't be feared. I had a severe health thing, three months later my hair fell out, three months after I am back to normal. Well, normalish :) Talk to your doc, and we dont judge.

  • Paul Sutherland
    Paul Sutherland

    He said "give you a heads up."😛🤤

  • blub232324

    2:20 looks almost like Matt Parker :)

  • edi

    Why are men and women storing fat differently. What´s the advantage of storing it mostly in the belly, rather than spread over a wider area? Since, we´re already on topic: why do many Afro-american women have butts that seem to defy gravity (not sagging, less bouncing and no moon-surface)?

  • Nikki Williamson
    Nikki Williamson

    My hair started falling out in 2017. It happened because I was very ill and on a lot of medications. I got better, came off the meds and it started to grow back thicker. Now I have a tonne of baby hairs that aren’t yet long enough to tie up but are long enough to get in my eyes...

  • Peldyn - Life with Cats
    Peldyn - Life with Cats

    I had a telogenic event and it was scary! Happened after I had a thyroidectomy. Lost most of my hair. Thankfully once my thyroid meds were adjusted my hair grew back.

  • IncontrovertibleTruth

    Well many people look up things on the internet first because at least in America so many people can't afford health insurance also people want to be educated about what's going on with their bodies

  • TheSzyko

    Please make a video about why your turn down the music volume when backing into a parking lot ( and what science is behind it). Yeah for sure it´s because of focus, but why does everyone do it? Maybe there is more to it. Much love, thx for your show!

  • X3DN

    My hair is bleached and colored

  • Gibraltar

    Duuude my hair is so long and I am a boy....my hair is longer than 80 percent of my female class mates.

  • Ibolya Szijgyarto
    Ibolya Szijgyarto

    Traction alopecia *cough*Jojo Siwa*cough*

  • veksu9

    Dandruff is caused by fungus. In special shampoos there are ingredients which kill those microorganisms. You are missleading people...

  • Jamail44

    I have really really bad dandruff, even if I wash my hair.

  • Sharon Johnston
    Sharon Johnston

    I actually have alopecia areata I always thought it was stress related. My dads a barber and in barber college he learned about hair disease and the way hair grows and he told me what it was and that it’s mostly stress related and it’ll grow back so I never really looked in to it I mean it’s probably only happened like 4 or 5 times in 3 years.

  • That Sagittarius Girl
    That Sagittarius Girl

    And here I am with my trichotillimaniac hands

  • pyukumuku 95
    pyukumuku 95

    My hair told me it was too hot so i cut it off. Im bald now.

  • David Oh
    David Oh

    I’ve noticed that ever since I started growing my hair longer, I’ve been losing a SIGNIFICANT amount of hair daily. I’m a male. Does anyone know why?

  • Chapter Eleven
    Chapter Eleven

    me, with an oily scalp and dandruff: sigh

  • Feral Crafter
    Feral Crafter

    Every time I go to a doctor, I'm billed thousands of dollars for a diagnosis of "I don't know" .... Sooo why go to a doctor?

  • Ico

    Sometimes I get extremely stiff, translucent hairs on my arms (only ever noticed it on my arms) that are very easy to pull out and sometimes there’s are multiple coming from the same follicle. Does anyone know what this is or what causes it?

  • Rachel Swanson
    Rachel Swanson

    I have dandruff. It started around 12 years of age. I've tried all kinds of dandruff shampoos none work. I have to only shampoo my hair once a week sometimes twice. I use shampoos for Africans because they're not as drying on my scalp. I also have to oil my hair once a week to two weeks. My son whose reaching 12 years old just developed dandruff too. I think its a hormonal thing rather than a fungus thing as you mentioned. Why would it only start around the time hormones change in a person's body? I'm so tired of dealing with dandruff.

  • John Smith
    John Smith

    8:24 "All sexes"? Seriously? You're a scientist. You know better.

    • zacharymli

      John Smith They are using very precise language to describe exactly what they are referring to in each case they refer to sex, gender, or biology. When they say all genders they are including humans who are intersex, because the thing they are referring to is equally applicable in everyone’s case. Science is well aware there are more than 2 biological realities.

  • TheMeganano

    I've been pretty self conscious about my hair ever since I was small. I've always had white hairs and I dunno why...

  • Lucky

    I am 10 and have a long white hair and my friends say it’s cool but ain’t my opinion

    • zacharymli

      Lucky Like one hair, on your head? Sounds kinda neat to me, but if you dislike it just pull it out. It may grow back sooner or later, and for some reason white hairs can seem to grow way quicker than any other hair, but you can just pull it out again. No big deal.

  • paul mryglod
    paul mryglod

    Mine is abandoning my head. What does it know?

  • BeUnotATVrobot

    Actually 6, that also you are a brainwashed TV Robot

  • Michael Seydor
    Michael Seydor

    Thanks SciShow for talking about alopecia areata. I have alopecia universalis which is a form of AA with total hair loss over the entire body. AA is one of the least understood and under-researched autoimmune disorders out there since there is no physical pain/restrictions. However, the negative psychological and societal effects can lead many of us to develop mental illnesses among other side effects. Any coverage on our disorder is appreciated as we collectively are trying to create awareness to fast-track research and clinical trials. Woohoo!

  • 69ouroboros69

    Biosex ... I was wondering what the correct term for that is. Thanks so much!

  • Dragon Landlord
    Dragon Landlord

    my epilepsy medication makes me shed, but i've got an thick head of hair so it's just a mild annoyance.

  • Falbert Forester
    Falbert Forester

    I disagree with the notes towards the end of, "It's impossible to diagnose conditions from your hair" - as I can recall reading about several cases where it's been proved that someone was poisoned with arsenic - provided by testing their hair.

    • gingergamergirl98

      Falbert Forester Yeah, with the correct equipment. Pretty sure he meant based on looks alone

  • David Ledesma
    David Ledesma

    Anyone gets sleepy when watching these videos?

  • crissyisajojofan

    You let a Chinese man doo doo in your mouth

  • The Wallaby Edits
    The Wallaby Edits

    Switching to a scrunchy helped from pulling my hair out

  • Dastreus

    I just have a couple shampoos for dandruff. THIS EPISODE MADE ME ITCHY

  • lexitaffy

    hi my server was raided on discord if you have it can you please join the raider banned everyone and i worked hard to gain alot of members so that upseted me i had 500+ members and 400+ were banned please join and share this with your friends and invite them :( i just wanted to be nice and i try to trust people but i always get screwed over so i invited their bot discord.gg/UHkRkqG please like this comment for it to be seen please

  • Taylor Craig Newbold
    Taylor Craig Newbold

    Male pattern baldness is a symptom of a weak moral constitution.

  • Are Gup
    Are Gup

    Am sorry but u really need to add other medical conditions and to go to ur dr for more deep eval.. Like a lot of dandruff for a person that never had it might be HIV sorry meant to say medical emergency symptoms.. or stop using others ppl brushes.. Ringworms causes bald patch on head.. ur body has a self warning signal to u to say hey go to the dr or something is wrong here do something before us to late. Just a little more in depth would b nice alway end with see a professional.. like excessive hiccups 4 days might also b a signal for the autoimmune disease hiv saying hey have this check out by a dr.. someone with halitosis should not blow food for a baby.. or kiss u u will get that bacteria .. meds can also do damage to the human system

  • Eric Cartman
    Eric Cartman

    #40 on trending

  • Rose L.
    Rose L.

    How about I just have someone give me a Amber Rose haircut and in no time it will grown evenly? What do you think?

  • Bruce Ramirez
    Bruce Ramirez

    Jojo siwa where u at

  • Danielle D
    Danielle D

    I had adult cradle cap!!! It was so weird. I think it could've been partially because I'm a model, and people are always putting weird products in my hair that I have no control over. I also traveled a lot and lots of different phs in the water etc, i suppose could contribute to the microbiome. I also just think it's important to scrub your scalp a bit with your nails, I read somewhere that this causes irritation so I stopped scrubbing my scalp with my nails, just my fingertips, and the buildup became more severe. Sometimes you gotta just dig in there!! Hah.

  • Deyvid's Channel
    Deyvid's Channel

    I'm dying

  • Madi Kuhn
    Madi Kuhn

    Jojo siwa should watch this video

  • Katie Kane
    Katie Kane

    Why do I get a "hair headache" when I ask it to go a different way? Really annoying btw

  • Emelia Smith
    Emelia Smith

    When I was in my teens I had a brief interesting period where two or three small patches of hair on my body just lost all pigmentation; My doctor couldn't work out why but put it down to some sort of stress reaction 🤷🏻‍♀️ (The pigmentation never return to those patches either)

  • Elizabeth Meier
    Elizabeth Meier

    😲 I'm nearly positive the first one you talked about is what is wrong with my scalp. It's been an issue for years. I just thought I had really bad dandruff 🤷

    • Molly Stringer
      Molly Stringer

      I'm positive that's what happened with my scalp too. One day it just stopped though? Idk, but there were like patches where it was really bad and I couldn't even push my hair over to the other side without feeling it.

  • Demon Sword
    Demon Sword

    those Damn T-saibous

  • Rania Toubia
    Rania Toubia

    What's a biosex female? Is it different from a woman ?

  • Wanda Richardson
    Wanda Richardson

    So, we are all mutants👌

  • vamsi krishna sadhu
    vamsi krishna sadhu

    Can you please make a video on ITP Idiopathic Thrombocytopenia Purpura. It is a rare auto immune disorder and there is no much information about it. Thanks.

  • Zee Hut
    Zee Hut

    Where is Jojo Siwa!?

  • Greg West
    Greg West

    Back hair is not weird. I agree it looks awful, but there is a strong correlation between High functioning creative cognition and hirsuteness. www.independent.co.uk/news/the-hirsute-of-higher-intelligence-1328285.html

  • Linda Ciccoli
    Linda Ciccoli

    When I went through menopause, my thick hair thinned out a great deal.

  • GiggitySam Entz
    GiggitySam Entz

    I'm loving the gender tolerance in your videos ♥

  • GiggitySam Entz
    GiggitySam Entz

    Thanks for such a well-researched and well-explained video!

  • Ghormi Bear
    Ghormi Bear

    I have PCOS and if i didn’t shave everyday I would have a beard it sucks and makes you feel less of a woman 😞

  • lillypod21

    I learned a crapton about telogen effluvium after I started losing clumps of hair a few weeks after recovering from dengue fever. I know it's just hair and that it grows back, but suddenly losing that much hair so quickly is really distressing. It's been two years since the rapid hairloss stopped, but I feel like my hair has not gone back to how thick it was before TE.

  • Thekrabbman

    If my scalp hurts a little after wearing a manbun (usually just after long periods of time), should I stop with the manbun or just use a "Lighter" bun?

  • Dávid Kertész
    Dávid Kertész

    biosex females


    Hey SCI. SHOW can you tell me what the heck is QUANTUM BIOLOGY?

  • Newtone

    Idumbbbz need to do an episode here

  • Florin Curteanu
    Florin Curteanu

    How to get a thick healthy hair: - Eat healthy (for a light blood); - Hidratare enough (2 litres of water per day); - Don't stress or get upset (because the stress hormones attack the hair follicles); - Go outside and get some vitamin D (but don't stay to much in the sun), or take vitamin D medicals if you are a vampire; - Wash it 1-2 times a week, especially if work in dusty places (no more often); - Don't excess with the comb or with special sprays/gels (try to let the hair free, natural, to breathe); - Be happy and laugh often.

  • TheFourthWinchester

    I do not have the body of The Rock. I cannot afford to go bald :( I recently lost a lot of hair due to Typhoid :/

  • Pink Bunny
    Pink Bunny

    I would love to have a looser hairstyle but its so frizzy that it has to be in a bun.... Well, gotta deal with a few hair falling out.

  • Joshua D
    Joshua D

    Remember, according to every advertisement featuring it, having visible dandruff means you will never get laid. The woman will see the flakes, have a disgusted expression, and walk away. Every time.

  • Joy Bradford
    Joy Bradford

    No more tight ponytails for me. No wonder my hair brush is so full of hair when I am done brushing it! Thank you for your great videos!

  • chickenfoot87

    I also have PCOS and it makes me grow a lot of body hair. I also have a deeper voice than is usual for a girl.

  • Glider5858

    If only I had hair loss around my anus...

  • chickenfoot87

    A fever changing the hair can happen in animals too. It's called a fever coat and can cause kittens and puppies to have a weird fluffy coat after an illness.

  • victorpapaavp

    I have exactly 0 non black hairs on top of my head, but there's dozens of blonde and red hairs in my beard. Any idea why? Am I a closet ginger?

    • gingergamergirl98

      victorpapaavp When my grandpa grew a beard, it had a reddish tinge to it. I suspect it’s something to do with carrying the allele, but not expressing it. Maybe beard hair is influenced by both alleles? Idk but it’s definitely, like, a thing that happens (facial hair being a different color to scalp hair)

  • Rachel Losacco
    Rachel Losacco

    In high school I got mono and was bed ridden for 3 weeks. About a month later, I was pulling my hair out by the handfuls (though I didn't look bald, thankfully). I think it might have been telogen effluvium -- over the next few months the missing hair was growing back and I had an awkward "halo" of new hair on top of my regular long hair. But is it common that it should kick in so much later after my illness?

    • CHEETAH RACE In YouTube
      CHEETAH RACE In YouTube

      It is not problem.hair has external functions for body ,not internal.not worry about it either u have gray , brown , black hairs.i will recommend don't scratch or pull out gray hair if u have.DONT TAKE STRESS IS IMPORTANT AND BE HAPPY

  • Zman Jace
    Zman Jace

    Well I'm not even 2 mins in and my head itches. Great.