Oddbean

I don't suffer from dandruff, and I have no medical credentials. But something happened to my dog which got me to thinking. A while back my dog developed a sebacious cyst on her back. Easily movable under the skin, either a sebacious cyst or a lipoma, I wasn't worried about it. One day the cyst was broken and the gunk and blood hardened into a scab over the wound, but the scab contained a lot of her hair matted together. I figured this happens to dogs in nature and it will get better on it's own. It didn't. As the hair kept growing, the hardened area pulled away from the wound which re-oozed, and the scab got bigger. Eventually it was a fairly large scale. I tried cutting it off but it was hard to cut and remove and I only got part way through it. It kept growing and oozing. Then one day I noticed all of her skin along her spine, from her head to her tail, was covered in rough flakes... keratin like flakes of skin. And now I was worried. Did she develop some kind of skin cancer? I took her to the vet, who didn't even really look at her skin (she seemed afraid of catching something) but thought I should consider putting her down. But she also gave me chlorhexadine and said to wash the scab with it (mixed with water) and try to dissolve it away, and just keep coming back washing more and more until it was gone. I did that and the scab dissolved away. I also combed all these large keratin flakes out of her wet hair (I washed her whole back), and quite a lot of loose hair came with them, and all the flakes came out, and now her skin felt normal again. The would healed properly this time and the flakes didn't return. So here is my hypothesis: Dandruff is an adaptive protection mechanism meant to separate matted-up-scabs from the wound they are attached to. When I look online I can't find this hypothesis anywhere. All the pages offer help on curing dandruff, none of them explain why it happens, what it's purpose is. This reminds me of Chesterton's fence: don't take down a fence if you don't understand why it was put up in the first place. If this is the purpose of dandruff, then human dandruff is probably just an aberration of the mechanism and curing it is probably fine. But it might help enlighten the specific conditions that trigger the genetic pathway. I'm probably wrong. But that is how science goes. Observe. Take a guess.... not being a scientist or vet with access to lots of dogs to experiment on I can't take this one any further.