"A very expensive perm" just made me spit soda all over my dash

Hank got that tenured professor look with his new hair

My mother had chemo too some 12 years ago, lost all her hair. It didn't grow back curly, but the chemo healed a 30-years old scar she had by her collar bone. Also, congratulations Hank, you are a hero!

I love that Hank didn’t pull away from being a science guy throughout this - even if he did it privately and away from the world. It is so important to remember who you are and what you love to do when you’re facing your own mortality! I am complex chronically ill which means mortality is staring me straight in the face but I have never stopped painting. I think our passions really keep us alive ❤

My mother has had bright green eyes ever since she had chemotherapy. She has had blue eyes her whole life. I'm the one that pointed out to her how green they are now. It's fascinating.

I love that Hank's approach has been "how can I use my experience of having cancer as an education opportunity?" Truly the best of us

My best friend in HS had to get low dose chemo for a benign brain tumor near the back-base of the skull, too close to anything vital to risk surgery. One of her biggest anxieties was her hair growing back different bc it was such a large part of her identity. Thankfully the only difference if any is some added waviness she enjoys, but i remember us having many tearful conversations over it bc there was so LITTLE for her to look up in terms of research to ease those fears. With how many cancer/chemo patients are out there, I'm shocked there hasn't been more research done!

As a former hairdresser, I have definitely noticed change of texture in clients who had chemo. I have been told by clients that a pregnancy or menopause have changed hair texture aswell, maybe theres a correlation to make? Super informative and interesting video!

I’m African American and my aunt is a breast cancer survivor. After chemotherapy, her hair became a much looser texture and was nearly straight. We were so glad her hair grew back at all, we didn’t even think much of it!

the chasing down of a reference line and finding it to come from some random source that no person has read for the last 30-40 years, is so real.

It's such a relief to see you doing so well. I was genuinely so sad hearing about the diagnosis because I grew up on this channel. I had a really rough childhood, and my siblings and I basically had zero education before getting out of it. This helped me so much in catching up, and I doubt I'd be the man I am today without it. Thank you for everything Sincerely, the 12 year old kid who had to play catch-up and made it to 24 just fine

Hank actually retired, this is just the 3rd Green Brother

I had breast cancer in 1999. It was a particularly nasty fast-growing sort, and unusually susceptible to chemo. I chose the most cytotoxic chemo, because it had the best odds of survival. Too many people loved me to let vanity call the shots. I lost every hair I owned for 6 months. I learned that the hairs in your nose keeps the snot from running out the front and that I needed to walk bent over so I wouldn't ruin my shoes. Originally straight flaxen blonde, when my hair grew back, it was red and curly like Little Orphan Annie! I have a theory on how/why it happened... In cosmetology school I learned that whether a hair is straight or curly has everything to do with the shape of the shaft of the hair follicle. A cylindrical shaft exudes straight hair. Wavy hair comes from a kidney shaped shaft. Flat hair shafts produce curly hair. While hair is actively in its growth cycle, no matter how close one shaves, the stubble remains in the shaft retaining its shape. As the hair continues to grow, it's business as usual. Chemo interrupts the growth entirely, allowing all of the empty follicle shafts to collapse and flatten. Later, as the new fine hairs are replaced, they curl along the flattened shafts. Over the course of several years, my own hair tamed into softer looser curls and waves as my medium textured hair proved dominant over follicle shaft structure. AGAIN, this is my best guess explanation. However, my theory is further supported by the tendency for long-term habitual hat wearers to have a strip of curlier hair where their hat band usually sits. Most likely due to the prolonged pressure from the hat band flattening out the shafts of follicles as they are in the resting phase in the "in-between" of the natural 5-7 year individual hair lifecycle. That would also explain the tiny patches of wild curly hair directly above the ears where frames sit for the bespectacled. Also, hair tends to become curlier on the side the elderly, infirm, or otherwise bed-ridden favor for sleep. With that in mind, if one is plagued by asymmetrical waviness It might just be a matter of sleeping on one's other side for a few years, to alter it.

Hank lost his iconic haircut, and gained some stylish curls. Hank: 2 Cancer: 0

I have much respect and admiration for you. You are part of my childhood and seeing you now still educating me even through your illness is inspiring.

@00:12 I actually think he looks younger now than in that photo from before the cancer. His face is fuller and the dark curls give him a more youthful appearance.

I have Chemo Curls!! I'm a 20 year cancer survivor, and I've had it 9 times, 4 different kinds of chemo! My hair is STILL 80's style curly; I was born with blonde straight hair and now it's brown and big bushy Bob Ross curls!! I recommend a good curl definer so it doesn't get poofy, and be mindful that Curly Hair is THIRSTY! Lots of moisturizers--And I'm SO GLAD to see you looking well!

I'm not sure if you'll see this, but my husband was just diagnosed with Hodgkins Lymphoma yesterday. I'm admittedly terrified because cancer is a very scary word. But honestly seeing your struggle and what you went through, and came back on the other side helps. So I want to say thank you for putting this all out there, and not shying away from the truth of it all good, bad and humorous.

Such a Hank move to turn a weird personal life event into an educational video for our benefit. Live long and prosper, Green.

So glad you are back and healthy. I love your bubbly personality. I used your videos for my Psychology class. You made learning fun. God bless you.❤

OMG, my wife not long ago went through 12 months of ray and chemo cancer treatment. Prior to chemo, her hair was very thick and absolutely dead straight. We couldn’t believe how curly she was after chemo was finished and her hair grew back. Now, after a few cuts (she normally keeps it very short) it’s give back to normal straight. Never thought it was a common chemo side effect.

While I'm relieved that Hank is a cancer survivor, I have to admit, I think I'm even more relieved that Hank is DEFINITELY still Hank - he hasn't let this change him, he's unbeaten, he appears to have come sailing through this the same man as he was when he went into it - I admire and appreciate him!

Congrats on being back as excited and energetic as always. 😊

We don't even mind if you are permanently bald, we are just happy to have you with us much longer. Not a lot of people with cancer have such luck. Glad to see you being better!

"maybe, a very expensive perm!" - Hank, I love your attitude, man. I'm glad you're still here.

So you not only managed to maintain your sanity, sense of humor, work, life, but you're actually using your experience and it's effect as additional subject of interest for a SciShow. Respect

i laughed so many times. thanks for exploring this topic hank! i'm so happy you're doing well!

Hank, I'm so glad that you made a video about this topic. Its been a question in the back of my mind since your remission and its a subject worthy of more research! It may not be the most important question to science, but any knowledge we can get about cancer treatments and their effects is invaluable to patients and their families so they can make informed decisions.

I went to high school with a guy who had leukemia. He had chemo three different times and said his hair grew in different every time. It had gone back to straight when I knew him but previously had been curly. They really should study this as it might teach us something about how cellular regeneration works.

I love that Hank uses his personal experience to help highlight things, and it's super interesting that an apparently well-known phenomenon is unstudied

Hank, I've been having a VERY bad day. I just want you to know that seeing you with a full head of hair brought a tear to my eyes. I'm so happy for you and your health, so happy that you are no longer going through the Chemo as that sounded very rough, and I just want you to know I love you brother. I'm so glad to see you doing well. PS. You look very handsome with curls!

You have always been a constant in my life, i love these videos and i am so happy you continued to make content even through chemo because you loved your job so much

Hank, my mom just got diagnosed with breast cancer and watching you throughout your journey has helped me immensely. Thank you for continuing to post and be here for us. We love you.

I was diagnosed with breast cancer a few months before you announced your diagnosis, so learning more about cancer thru you throwing yourself into research has been sort of comforting! My hair came back curly as well, and I have a cool white streak now instead of just a few greys 😂

I really appreciate how you keep these things honest and mention that “we need more studies”, to hopefully prompt such. I’m glad you see you’re doing well. And your approach to using even your own experiences to fuel questions and answers in science - is very refreshing. Thanks, as always!

One of my friends has lost her hair twice from chemo and both times it grew back different - both color and texture! She’s losing her hair again, due to another round of intense chemo, and the excitement to see how it grows back this time has genuinely helped with the process.

I love how Hank always seems unconditionally positive. Every day he is gracious and therefore everyday he is at peace and happy. A true role model

I am glad you’re okay Hank. The world would not be the same without you and I’m glad you have an analytical, scientific approach to how cancer has affected your cells and your body. We love you ❤

i hope you live for a long time to come, because you are truly a blessing for this planet

Glad to see you doing well! ❤

I’m not a scientist but I am a hairstylist and the vast majority of my clients are over 60. The “chemo curls” are definitely prevalent as well as change in color that you mentioned. Another thing I personally have noticed is patches of hair that become permanently coily in people who have fairly straight hair following a major operation; specifically ones where they are under general anesthesia for extended periods. We need to get some studies going.

In Portugal, the reverse happened. A singer had a great curly hair. After chemo, it came back straight. Marco Paulo is his name.

I"m so glad to see you make this video with your new hair! Welcome to the curly club

Thank you for loving your job I appreciate u

MOST USEFUL VIDEO I HAVE WATCHED IN YEARS!!!!! I am a husband with a wife that had NON- Hodgkin's Lymphoma. Your videos are laser focused for me and am loving every second of them. We are about 18 months out from diagnosis, 7 or 8 months out from final chemo trip. As you noted, hair loss was a big thing for my wife. Whe had quite nice very long black, (typical Asian hair) and in her mid 40's. She had a very high level of grey hair prior to chemo. After chemo, a week or two, if I remember right, it all started falling out. So we got the trimmers and buzzed it off. No need to delay the length of suffering watching clumps fall out. It grew back for her, although it does seem quite a bit slower that what was normal before. But now, her hair is the natural almost pure black as in her youth, and she is loving it. For me, the smile on her face is the bonus I was hoping for, as we suffered the mental stress together. Cannot thank you enough for the abundance of help you served up with a smile mostly, and encouragement. So, I watch your channel daily for updates. Again, Thank you.

I also panicked when told I would need chemo ... I had hip length, very full hair that was part of my identity, and I was completely freaked about losing it. The oncologist barely reassured me, but her nurse and PA both said the chance of hair loss on this specific chemo was very low. And they were right - I didn't lose any hair due to chemo. However, the stress of dealing with cancer, radiation, surgery, and recovery caused three bouts of major teleogenic alopecia (stress induced hair loss). I probably lost 2/3 my hair ... fortunately it stopped before I developed any bald patches. And the hair is growing back, in the same color and texture as my older hair. And the cancer is "stable", so I'm a lot less stressed.

OMG, I'm so glad you're ok! I love your hair ❤

Oh my god, I had no idea you were going through any health issues til just now!! I'm so glad you're here and still kickin' ass and teaching us scientific names! My mom's hair got pretty curly after she went through chemo, too.

I do gotta say, you looking good with the chemo curls

I lost my hair to chemo last year and now its growing back the same texture as before (except for my body hair, which is growing back very thin and fine) but looking in the mirror is like looking at a stranger. Short hair just isnt who i am. It will take years for it to grow back to its former length, so yes, this subject still touches me deeply. Thanks for looking into it 😊

Hi Hank - nursing student and future researcher here! From what I've heard from medstudents and researchers within oncology, which is about (exactly)four people so take this with a grain of salt, the problem with a reaserch project targeting this angle is that it has a very low chance of getting accepted to get funding. This means there are two options: either fund it out of pocket or cooperate with a pharmaceutical company, making the research occur from a possibly unethical angle. Neither of these options are good for peer-reviewing or even getting the article accepted making the entire research "all for nothing". Plus - there are other research projects within cancer treatment that needs "prioritization"(not my words). It's a very interesting angle though and if people indeed decide to opt out of chemo due to the fear of the hair changing - one can try to get support and funding for a project from that angle. However, the risk of getting denied funds seems to be the main reason why those researchers don't plan on getting into this. One could possibly do a few qualitative studies about this fear in order to increase the chances though... I'll keep this in mind!

Weirdly, I got an ad for proton therapy cancer treatment on this video. Good job algorithms, you’re doing your best!

As someone with curly hair, hearing Hank say it's a lot more work made me laugh. Yes, Hank, welcome to the club, happy to have you here, haha. Also hope we can learn more about this, because it sounds super interesting!

My mom who is currently going through her 3rd time with cancer. Always loses her hair and her natural hair before was super curly and course, she’s of African descent. Every time that it grows back it comes back curly but not as course almost like baby soft curls. This video definitely got my attention. Also, nice curls Hank. Work’ em!

I was so happy to know and see you that you made it. You and the show keep me from doing dangerous things doing a a hard time of my life. I wish I could done something for you. You have shown me new and interesting things!

I'm just glad he made it through. Much love for the channel.

We love you, Hank! Glad to see you are doing better ❤

My grandmother died January 7th of this year from stage 4 breast cancer, just a day after my birthday. Thank you for helping promote cancer research and I am glad you are well.

HANK my good friend just went chemotherapy for a common cancer, and your videos of your thoughts/feelings through this process have been so helpful for him AND for me to understand some of what he’s going through! thank you!!

So glad you're back!!!!

As an overcomer of lower esophageal cancer (2011-12) myself, I wanted to applaud, thank and admire you for your selflessness and generosity in the way you have been sharing your cancer ordeal with the world. This had undoubtedly helped numerous people in numbers and ways you will never know, but can be assured have occurred. I wish you well, and a full recovery. Thank you, be well, and -- keep smelling the roses!

I did notice your hair came back curly! I was curious, but too polite to say anything haha. It's wild that there isn't any research on this. Can't wait to see how you rock your new set of locks, though!

When my boyfriend and i were juniors in high school he had the same exact type of cancer as you. pre chemo his hair was very similar to your pre chemo hair (but slightly redder) and then after chemo it grew back curly exactly like yours now too! but then as months passed it slowly got wavy and then back to straight. but definitely for a little while it was super duper curly like poof level.

Hank , you never cease to impress me with your every video.

Before chemo as a kid I had straight hair. It came back wavy!

I had a patient once, who was on a mood stabiliser/anti-epileptic medication, but her hair began to fall out. We stopped it, while she had only lost, a 5cm/2" circle, and that circle grew back totally curly, in an otherwise straight head of hair. It amused her more than anything else.

So glad to see to see you all well!

Good to see you man! ❤

I found out I had stage 2 Hodgkin’s lymphoma several months before you announced you also had it. It was so crazy and weirdly comforting to know of someone who also was going through treatment of this more rare cancer and hearing about your journey helped make me feel less alone. My hair is now also growing back curly and I’ve been asking other people with curly hair how I’m supposed to take care of it! I’m glad we both beat it, together….. sort of ❤

This video gave me a sense of relief, happiness and wonder all at the same time. So glad to see you again Hank! And with curly hair 😁 looks awesome!!

This guy is the reason I watch UKposts. Thank you brother. Your a world treasure

I could cry. I have literally been quite saddened with the news of your diagnosis. I'm most relived at looking at your hair. may you forever stay healthy sir

The wife and I were saddened when we learned about your illness. You are our favorite presenter on SciShow. We are glad you are back, curly hair and all. It rocks...

Interesting video, I’ve always loved watching your content, health is very important I’m glad your recovering, we wont you around a little longer, looking forward to seeing your content in the future. Keep up the good work

Thank you for this video! It was nice to learn the little bit we do know, and I hope we learn more soon! Losing my hair was very traumatic, and I did spend a lot of time worrying it wouldn't come back or it would be different. Thankfully it is even more curly than it used to be!

The psychological impacts of side effects like hair loss can't be understated, especially for women - and it's not just head hair that can be impacted. My mother was far less concerned about being bald (which could be covered up by hats & wigs) as she was about losing her eyebrows... they were already quite light & fine, and as someone who rarely wore make-up, she had no desire to draw them on. Her hair thinned out quite significantly during her 2nd round on the chemo & radiotherapy train, but when she had the most aggressive chemo the first time round she only lost (of all things) - _body hair._ We joked about her "beach-ready" legs and how she could throw away her shavers & wax, but what was most noticeable was how much faster she felt the cold... the hair on your arms, neck, etc does provide a thin barrier to heat loss (even for women) and she went from routinely wearing short-sleeved tops to always wearing long sleeves because her arms would feel cold even in a warm room. There are so many little quirks of the human body that go unnoticed until they stop working properly.

Great stuff, thank you for this. My grandfather's hair thinned and turned grey then white through his 60s and 70s... in 2008, when he was 80 and fighting cancer, chemotherapy first took his hair, then it came back... thick and dark brown! Keep doing science things, it makes us all better over time

Love that you're looking at this phenomenon and calling for more research, Hank. I'm wondering about that estrogen angle you mentioned. I had very short hair for about 10 years, but I grew it out during the pandemic. It came in way more curly than my hair ever was in the past. The only physically significant thing that happened to me during that time was....menopause.

love u Hank! Happy to see u doing well

THANK YOU SO MUCH FOR THIS! I had dead straight hair all my life until chemo. I had the nasty stuff (doxorubicin, aka the red devil) and lost all my hair, including the hairs inside my nose. (My nose ran constantly until they finally grew back.) And when my hair grew in, I had spiralling Shirley Temple curls. Like you, none of my doctors could tell me why. Women's hair often changes during menopause and my cancer was estrogen positive so I was put into early menopause so some of them blamed that. Others talked about follicular changes after chemo. But no one had a definitive reason why and no one seemed terribly concerned about what it meant to me personally. And curly hair is really hard work! My chemo was 3.5 years ago and while the curls have loosened, my hair is still absolutely curly, so I think the curls are here to stay for me.

The Green Brothers are such a gift.

Praying on your success!

Glad you're on the mend; wishing you continued good health! I was treated for breast cancer a decade ago, with some fairly strong chemo (AC-T: Adriamycin, Cytoxin, Taxol). I had no problem being bald (felt quite badass, in fact), but my chemo curls weirded me out because I kept seeing Shirley Temple in the mirror and wondered whether I should sing "On the Good Ship Lollipop" whenever I stepped out of the shower. Thanks for the education and for your enthusiasm!

My hubby developed alopecia when his mother died when he was a child of 10. He then went on to have testicular cancer at 40 and he did indeed have chemo curls! Once his hair grew back. When he saw your bald picture he said Ahh, brothers in arms hey! Very interesting and I love your perky presenting style :)

Hank looks strong and healthy

Thank you so much to answer this question!! I asked this question in a comment of one of your recent videos where we could see your hair became curly. As I didn't know where to properly address this question to you, i asked it in the comment section. I am soo glad you answered it (even if it was not for my comment), I witnessed so many of my friends with curly hair after chemo.

I’ve never had cancer, but my hair’s color and texture changed after a big traumatic event in my mid 20’s. Love seeing the actual science behind hair growth and changes!! Fascinating stuff!

I work at a cancer center and we have a machine that is supposed to help prevent hair loss. The pt wears the inside cap part and then the machine is hooked up to it and circulates cold water through the cap, making your head cold. The idea is that the cold makes the blood flow constrict and the chemo can't get too close to the follicles, saving your hair. It's not 100% guaranteed, but the company says even if you do lose your hair, it's supposed to grow back faster. It's a really great option for those who would potentially deny treatment due to hair loss, and it does work, at least for some people. No idea of the stats or actual research, but I have seen women who use it and don't lose their hair from treatments that do cause loss of hair, like taxol carbo.

"Because its just cool to know things." My man always has some awesome quotable moments! P.S. i think you rock those curls by the way!

Glad you're still with us!

I’m so happy to see you are recovering so well.

*looking at old photograph of self* “Look at him, so young and free and unconcerned with mortality!” That is definitely, as the kids would say, a Mood™️

Yep, heard of it, my ex's sister had chemo and she "went curly" (to use a medical term) and almost a decade later it still hasn't fully returned to straight. They say you either get a superpower or curly hair, looks like you're not going to be getting that call from Marvel.

Missed you Hank. Glad to see you’re doing well! Cool video on how chemo works in hair

I realized that when your videos pop up, I am always kinda aware of whether it was recorded before or after chemo based on whatever's going on with your hair, creating this interesting BCE/CE dichotomy. You do seem slightly different, but only in a more kickass and powerful way, like the difference between Gandalf the Grey and Gandalf the White. You went through this deeply transformative thing and came out somehow more invincible and wise. Thank you for bringing us with you on your journey.

I work in research as a nurse, directly administering treatments for clinical trials. I wrote my (undergrad) dissertation on women's experiences of chemotherapy-induced alopecia and really enjoyed learning about it. It's arguably the side-effect that has had the least dramatic change from chemotherapy's introduction in the 1970s, given the development in things like anti-nausea and anti-diarrhowa drugs, etc. Although there is scalp-cooling, it can't be used in all cases (e.g. haematological cancers) and for all chemotherapy drugs (if it has a long half-life or long infusion time). It's interesting to learn that we dont really know much about WHY it happens though! That's crazy!!!! Thanks for posting ☺️

It's a PBS first! Let's invest in this!

Congrats on the recovery

I think it looks great. Keep bringing the great sci shows!

the curly hair looks so good!! Also, thank you for talking about the experience of being a patient! As a chronic-illness gal, I feel so seen!