A few years ago I started coloring my hair - it had gone from a salt-and-pepper look I really liked to so much “salt” that it looked mousy.
Shortly thereafter I started using minoxidil. Turns out I’m one of the lucky folks for whom it works really well.
Now like so many of us Covid-19 stay-at-homers, I’ve stopped using hair color. And whaddaya know, my natural hair color seems to have returned to the salt-and-pepper mix I actually like.
Two theories: first, a larger proportion of my hair follicles that had dropped out and were reactivated by the minoxidil were dark ones. Second, I’m imagining things.
I’m curious what knowledge/experience others can share on this.
I have no direct knowledge of Minoxidil, but I do know that in both my parents’ cases, when they were on chemo, their dark hairs fell out, and they grey ones stayed. My father had VERY thick hair, and a lot of grey, so while he was on chemo, he lost only his remaining dark hair, and still had a lot of hair (but it was pure white). He died without ever coming off chemo, so I don’t know what would have happened, but when my mother went on chemo, she had a lot of dark hair, and a little grey. She lost all the dark hair. It grew back eventually, but not quite as thickly.
I also met a woman once who had idiopathic alopecia, who had lost her hair as a teen, and oddly, had some hair (not a lot) grow back when she hit middle age. It was all grey.
So this is all anecdotal, but it would appear that grey follicles are somehow more resilient than pigmented ones. I have no idea why.
It seems therefore fair to speculate that whatever caused your hair loss, disproportionately affected pigmented follicles, and that this is a typical phenomenon.