I think when it comes to hair, one of the things that fascinates me the most is the genetics.
Both from the point of view that all you can really, truly do is to maximize the potential genetical maximum through proper care and handling. You can't out-nutrition or out-care your genetic blueprint.
...But also because it seems like so much of the textbook knowledge out there just seems so plain wrong.
Is it just me?
How often do you hear/read that the active growth phase (The anagen phase) is genetically predetermined and is only 2-6 years?
How often does that seem to be true?
I always wants to say "Well, yes, maybe for balding men, I guess" but I have seen enough balding men with ponytails to say that isn't true. Two years of hair growth is around shoulder length for most people, three years around armpit length. I'd say two years is wrong, but three might be an option if we speak of all people in general, since many with fine, fragile or very curly hair have trouble reaching more length. But two? Nah. Not buying it.
And then there is the maximum active growth phase, so often quoted to 6 years. That should be around tailbone or classic or so depending on your height. Of course when you grow your hair for so many years, you are pretty much guaranteed to trim a lot of the ends off. Actually, I would say it's pretty damn hard to grow nice-looking hair of that length if you don't trim on the regular!
Anyways. Maybe it's just me, but the numbers quoted of years for hair growth in the anagen phase always seemed off to me.
Back in 2019, Mr Igor and I did the 23andme tests, which is a story in itself.
Here and the follow-up
here.
It was really interesting from a hair genetics point of view too, because I didn't know there was so much depending on your genes when it came to hair. Now it almost feels like a "Well, duh?" kind of thing, but I guess I never really thought of it before.
Before that, I just knew of the basics: pheomelanin gives you red hair tones, and the amount of eumelanin regulates how dark your hair is.
I didn't know that photobleaching was a genetic factor. I always thought it was sort of a by-product of having lighter hair, especially when it seems to be so common among native Scandinavians. Everyone I know with lighter hair gets it lightened in the summer. I mean, most things, such as fabric and wood goes paler when exposed to sunlight too?
The loss of colour comes from a loss of protein and structure in the hair, so the paler colour is a sure sign of damage to the length. I'm only slightly obsessed with SPF in my haircare products. After all, skin can to some degree repair itself after sun damage. Hair can't.
But supposedly a massive 48 genes plays a role in whether your hair loses colour from sunlight or not.
How much or little curl you have in your hair is said to depend on the shape of your hair follicle, and this also involved way more genetics than I expected.
Maybe it's just me, but I find the sheer numbers of genes involves in something so simple to be fascinating. I remember us using hair colour (As well as eye colour) as simple examples for Mendel's second law in primary school biology, and now as an adult I look at this genetic mess that determines my hair colour and learn that it isn't that simple!
I would really like to know more about how this works though. It seems for most people, their hair pick a narrow range of colours to grow, but for me, I can find individual hairs ranging from light blond to dark brown.
(And no, I know mr Igor isn't cheating and I'm finding someone else's hairs all over our place. I would be very impressed if he managed to find a side piece who also grows 1½ meter long hair. As far as I know, that's not mr Igor's thing)
Another hair related trait I was surprised to see pop up was dandruff. I have a tendency to get some very light dandruff in the late autumn/early winter, but I always wrote it off as being due to the weather changing: When it gets cold and wet outside and hot and dry inside, it always triggers some light scalp irritation. But since 23andme doesn't predict that I have dandruff, it might be more of a sensitive skin issue? That I do have.
I was genuinely upset that they only gave me a 6 % chance of having red hair. I always felt I had some red tones in my hair and really appreciated them. But meh.
I don't care what they say though. I think red hair is amazing. Maybe it's the rarety of red hair I like. Both for the mostly-Celtic genetic variant and the Melanesian genetic variant. I just think the colour is really pretty!
The red colour comes from pheomelanin, but you also need to have lower levels of eumelanin for the pheomelanin to really show through the dark colour.
It's funny: The widows peak is another one of those traits I remember from biology class. Along with little tidbits like that how you fold your hands is genetically predetermined (And folding them opposite feels really crazy wrong) and folding left thumb over is the dominant gene. But maybe that's wrong too. I mean, it's been over two decades since I sat in a biology class, so I actually kind of hope my knowledge is outdated?
I also remember that male pattern baldness was tied to the X-chromosome, so since men only have one, it explains why men usually either go bald fast or not at all. They simply don't have a "backup" to soften the effect, like women do. The knowledge seems to still hold true today. But since 23andme didn't bring it up for Mr Igor, I guess that it isn't that simple? Or maybe they don't want to get sued.
The widows peak also have a bunch of genes involved. More than you would think. Okay, less than for some of the other traits, but still.
Now, one hair related trait I was slightly disappointed in not seeing any info on was hair growth. It would have been fun to see what my maximum genetic capacity is, but maybe such info does exist?
After all, everyone always assume my hair grows a lot faster than it does, but I only get 1,5 cm each month and 2-3 months in the middle of the summer with 2 cm.
It's a nice and very average growth rate, but really not impressive in any way.
It would have been fun to know if I'm even close to maximizing my potential growth rate, or, dunno, I need to eat more proteins?
