I'm a 46 yo Caucasian female. I've had SD of the scalp for approx 10-11 years. Like everyone, I've tried SO many things to cure or even just help it. Many of the things that have helped others have done nothing for me.
I don't have flare-ups -- I have constant SD. I switch time between a very arid, and a very humid climate, and that has not seemed to make any difference either.
My default way of handling it is to put something–I've switched around from coconut oil, to plain yoghurt, to conditioner mixed with oregano oil, and currently am using a combo of lemon juice/veg glycerin/oregano oil)–on my scalp, leave it 2-8 hours under a plastic cap, and gently exfoliate the scales off w a comb.
Tho I've experimented with dietary stuff before (and I tend to have a much healthier diet anyway than most accounts I read), three weeks ago I started what is basically a Whole30 diet, plus leaving out eggs and nightshades, and very low sugar (no sugars of any kind, no dried fruits, and just 0-1 pieces of fresh fruit per day). At the same time, I've started spraying my scalp with a mixture of veg glycerin, red cedar essential oil, red cedar tincture, and lemon juice. I still have to exfoliate my scalp as described above, about every 3-4 days.
This is the strictest diet I've undertaken, and I've also started sleeping more (I used to work nights) so I'm really hopeful some change and improvement will take place. I am already a height-weight proportionate, very fit person (I exercise extensively every week) I also have absolutely no other health issues – no asthma/hay fever, no other skin issues (the rest of my skin is extremely healthy), no allergies, no digestive problems, and I get sick with even a cold less than once every 2 years.
So why my scalp SD is so crazy-making and intractable has always been a mystery to me.
Michael, thanks SO MUCH