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Premature Graying of Hair: Review with Updates

119 点作者 luu6 个月前

24 条评论

notamy6 个月前
&gt; Vitamin B12 deficiency can cause PGH through unknown mechanism. About 55% of patients with pernicious anemia had graying before 50 years as compared to 30% in the control group.[32]<p>&#x2F;soapbox<p>Get your B12 tested (before taking supplements!).<p>B12 deficiency is known to present in many ways, and also to be often overlooked in clinical settings[1]. It’s known that not everyone presents with the anaemia from it[2], which is often why it’s skipped as a diagnostic option. Additionally, long-term&#x2F;severe deficiency can present with symptoms almost identical to multiple sclerosis[3]. Deficiency of other B vitamins, such as B2, can cause a functional B12 deficiency as well[4]. It’s also known that supplementation will falsely elevate levels even in the presence of a deficiency.<p>&#x2F;unsoapbox<p>[1] <a href="https:&#x2F;&#x2F;www.mcpiqojournal.org&#x2F;article&#x2F;S2542-4548(19)30033-5&#x2F;fulltext" rel="nofollow">https:&#x2F;&#x2F;www.mcpiqojournal.org&#x2F;article&#x2F;S2542-4548(19)30033-5&#x2F;...</a><p>[2] <a href="https:&#x2F;&#x2F;www.bmj.com&#x2F;content&#x2F;383&#x2F;bmj-2022-071725" rel="nofollow">https:&#x2F;&#x2F;www.bmj.com&#x2F;content&#x2F;383&#x2F;bmj-2022-071725</a><p>[3] <a href="https:&#x2F;&#x2F;researchonline.nd.edu.au&#x2F;cgi&#x2F;viewcontent.cgi?article=1215&amp;context=health_article" rel="nofollow">https:&#x2F;&#x2F;researchonline.nd.edu.au&#x2F;cgi&#x2F;viewcontent.cgi?article...</a><p>[4] <a href="https:&#x2F;&#x2F;www.iomcworld.org&#x2F;articles&#x2F;paradoxical-vitamin-b12-deficiency-normal-to-elevated-serum-b12-with-metabolic-vitamin-b12-deficiency.pdf" rel="nofollow">https:&#x2F;&#x2F;www.iomcworld.org&#x2F;articles&#x2F;paradoxical-vitamin-b12-d...</a>
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OutOfHere6 个月前
Regarding PABA, I have been taking 500 mg&#x2F;day for years, and it hasn&#x27;t done anything at all for restoring my hair color or even for freezing further change. A much higher dose of it can be risky and it&#x27;s not worth the gamble.<p>I have also been taking B5 as both calcium pantothenate at 500 mg&#x2F;day and also as pantethine at 300 mg&#x2F;day for years, neither of which has done anything either in this context.<p>Similarly, B12 hasn&#x27;t visibly helped either.<p>I suspect that copper is the issue with me.<p>The lowest dose of MitoQ, a 5 mg capsule per day, had lowered my blood pressure significantly after a month of use, well below normal, approaching an unsafe low. Moreover, it took another month after discontinuation of MitoQ for the blood pressure to normalize. I shudder to think how much more powerful SkQ1 would be if taken orally. My first impression is that SkQ1 seems more relevant for local use than for systemic use.
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james_marks6 个月前
&gt; INTRODUCTION Haalthy hair is a sign of general well-being and youth.<p>Not exactly confidence inspiring when the very first word is a typo.
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A_D_E_P_T6 个月前
I had been looking into this recently. My beard is graying and it&#x27;s annoying me excessively.<p>10 years ago, the research consensus behind hair graying was, &quot;we don&#x27;t know what causes it, lol.&quot; Today, it&#x27;s a little bit better understood -- though <i>far</i> from completely understood.<p>There&#x27;s a handy review article here: <a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC10535703&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC10535703&#x2F;</a><p>To summarize, there&#x27;s no known agent that can reliably repigment gray hair. Sometimes powerful drugs repigment hair as a side-effect.<p>Hair graying results from the dysfunction or loss of melanogenic melanocytes and the depletion or immobility of McSCs, often due to aging or stress.<p><i>Lots</i> of cellular signalling pathways are involved. The Wnt&#x2F;β-Catenin pathway promotes melanocyte stem cell (McSC) proliferation and differentiation, while the MC1R&#x2F;cAMP pathway, activated by α-MSH, drives melanin production via the MITF transcription factor. The SCF&#x2F;c-KIT pathway supports melanocyte survival and function, and the Endothelin&#x2F;EDNRB pathway stimulates both melanocyte proliferation and melanogenesis. In contrast, the PI3K&#x2F;AKT pathway inhibits melanogenesis by suppressing MITF activity, and the TGF-β pathway maintains McSC quiescence while inhibiting melanogenesis.<p>Stress is actually a factor because activation of the sympathetic nervous system can deplete McSCs, and neuropeptides like CGRP, SP, and VIP, can either enhance or suppress melanogenesis in ways which are, as yet, unclear. Dermal white adipose tissue (dWAT) near hair follicles also plays a role by secreting factors such as adiponectin that affect hair growth and pigmentation.<p>A drug to reverse or prevent hair graying would be very welcome, so I hope that the phenomenon becomes better understood in the near future, and then we get products that work.
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gnulinux6 个月前
In our world today it seems impossible to complain about stress. Everyone around me from boss to family to even therapist keep telling me to remind myself of how great of a life I have and that I should know better than to complain. But it feels to me like I&#x27;m drowning in an ocean stress everyday with no way to escape it. I keep being compared to others who can seemingly take the stress well and am questioned why I can&#x27;t take similar level of high-stakes, indeterministic responsibilities with severe dangers that are beyond my control, and little to no positive pay-off for me. Some people around me are extremely health conscious, they avoid all kinds of chemicals, eat religiously well, work-out regularly, sleep well etc yet when they show obvious signs of stress because they&#x27;re working 12 hours a day in their torturous FAANG job, I&#x27;m treated like an antivaxxer for pointing it out. In this world of hustle culture, it seems like a taboo to talk about how unhealthy stress is. Stress today is like 70s cigarettes, everybody is doing it, so no need to worry about its health effects.<p>And yes I have graying hair at mid-late 20s. Sometimes I&#x27;m astonished how people don&#x27;t complain about their stress levels. I feel weak, child-like, immature, and feeble being unable to tolerate maybe 10% of what my wife can.
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abrookewood6 个月前
Slightly off topic, but I have found a Vitamin B supplement all but eliminated my migraines. I was getting them every 1-2 weeks and then, after taking Vitamin B regularly (to counteract alcohol consumption during the festive season), I realised I hadn&#x27;t had one in ages, despite running on reduced sleep (which seems to be my main trigger).<p>Anyway, I always make this comment anywhere I can because migraines are horrible, vitamins are cheap and maybe it will help someone else (obviously anecdotal; sample size of 1; I can&#x27;t find any supporting research etc).
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elric6 个月前
As someone who started balding at ~19, I would have been very happy with grey hair instead. One person&#x27;s self-esteem damaging condition is another person&#x27;s hope.
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Ancalagon6 个月前
Man I sure know a lot of early 30 year olds with graying hair
ivolimmen6 个月前
Well I have gray hair since I was 16. It never made me feel insecure.
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butternet6 个月前
Leaving aside other health concerns grey hair can be attractive on all genders and should be respected and celebrated.
shitter6 个月前
&gt; In men, graying first occurs in the temples and sideburns. It spreads to the vertex and rest of the scalp involving the occiput the last.<p>My graying started when I was 15 and first appeared as a single silver strand at the center of my hairline. At 28, I now have a cluster of them in that center spot, as well as diffusely all over my head, including the occiput. I think my temples and sideburns were actually relatively spared.<p>Also of interest to me: once in a blue moon, I shed a hair that appears to be <i>reverting</i> from gray back to pigmented -- it&#x27;s gray close to the tip and black closer to the root. I wonder what factors might cause this reversal.
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trhway6 个月前
There seems to be a lot about immune system activation attacking melanocytes like this:<p><a href="https:&#x2F;&#x2F;www.uab.edu&#x2F;news&#x2F;research&#x2F;item&#x2F;9390-study-explains-one-reason-hair-can-turn-gray#:~:text=Hair&#x27;s%20graying%20is%20linked%20to,can%20decrease%20pigmentation%20in%20hair" rel="nofollow">https:&#x2F;&#x2F;www.uab.edu&#x2F;news&#x2F;research&#x2F;item&#x2F;9390-study-explains-o...</a>.<p>Thus not surprisingly “Covid and gray hair” brings some results too, including reversing of Covid associated gray hair.
amarcheschi6 个月前
My grandfather started having white hairs at 20, I&#x27;m a bit older and I have a few strands of white hair. Honestly, I love white hair. It&#x27;s not very noticeable on me though, I get it can be embarrassing
zingababba6 个月前
I started graying when I fucked around with nicotine for a bit.
faraaz986 个月前
It can also be caused by autoimmune thyroidism
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n1b0m6 个月前
I was diagnosed with hypothyroidism a decade ago and it seems to coincide with premature graying in my 30s
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sterlind6 个月前
I started going gray at 16. My dad would pull my gray hairs out and marvel at them whenever he saw one - without thinking to ask first, of course. they joked it must be from stress - disquieting that it might have been metabolic, and that they never considered taking me to a doctor.
dukeofdoom6 个月前
So what&#x27;s the best brand for coloring grey hair. Preferably non toxic.
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donatj6 个月前
I started graying in my mid twenties, I am in my late thirties now and my hair is a little over half gray at this point. I would frankly like to do something about it, my wife has been insistent that I don&#x27;t because she likes it.<p>The possibility of it being some sort of vitamin deficiency that this raises has me feeling like I should at least get my levels tested. I can&#x27;t imagine that it is a B12 deficiency however due to how much canned fish I consume. It&#x27;s become my go to easy lunch since the beginning of COVID.
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on_the_train6 个月前
This title had me hoping that this was a gwern article
slt20216 个月前
TLDR: root cause is working with dynamic and weakly typed languages and poorly documented and maintained spaghetti code
theultdev6 个月前
tldr: stress
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mxxc6 个月前
lol at scientific papers using the word &quot;caucasian&quot; like it&#x27;s the 70s
sandebert6 个月前
OT, but I can&#x27;t not notice the wild domain.