That hairline is actually amazing, i never had that even when i was 10
I do take vitamin D 200 µg a day. I did have some dandruff issues in the past in that area, but not currently.
I take all kinds of vitamin supplements.
Dandruff is a telltale sign of some inflammatory/immune activity which is abnormal.
200 thousandths of a milligram may not be enough especially if you're not absorbing it properly which in my particular case I was not.
The thing I can recommend for you to do which I had to do because it's not always sunny where I live is that I basically got a reptile sun lamp, and I got one of those microphone stand arms that can extend and move and I attached the light to the stand and I basically would lay in bed with my shirt off facing away from the lamp at a good enough distance that I would not get burned and it definitely helped my energy levels.
Sadly getting enough vitamin D for many people can sometimes only involve naturally creating it due to sunlight exposure.
This year I felt like absolute garbage, constantly tired and dizzy until I started doing this particular therapy for 30 mins a day until I felt like my body was producing enough.
Either that or just get outside like a normal person if there's enough sun in your part of the world.
That is one thing you can try, but if you do have any sporadic red inflammation of the scalp accompanying your dandruff, you need to see a doctor. When I was 26 I lost an extremely high volume of hair in a very short period of time in a patterned way that I thought was just Androgenetic Alopecia. I went to the Doctor and got on mometasone and then betamethasone and was on that for eight months and my hair recovered.
You might not require that much to keep your hair in check, but patchy loss and then regrowth is a sign of immunological and inflammatory issues, of which they can deplete certain nutrient reserves such as vitamin d but also b12. Another thing I should offer is that after the first year of regrowth I started feeling really tired and weak with a whole host of other symptoms, and started on an aggressive treatment of injected and methylated b12 which may have also boosted my hair regeneration since my b12 levels were at the point of pernicious anemia.
If you're taking b12 make sure you're taking methylcobalamin, any other form is garbage if it's taken orally and it is not readily usable by the body.
If you're not using nizoral, you probably should be as a precaution against certain types of seborrhea causing hair issues.
I wish I had the courage to have taken a picture when my hairloss was at its worst, but it was so diffuse and my scalp so red and angry and sore that I had to basically buzz my hair down to nothing. I was very ashamed of it and quite depressed over it.
This is about how bad it was (not my photo), and I'll provide a real after pic of what I looked like after I recovered which took a total of about two years due to the fact that I did have a shedding event after tapering off the corticosteroids, but it wasn't anything even coming close to what happened initially.
But if I can go from what is depicted in the first photo to what I ended up as, other people can as well, my recovery didn't involve taking estrogen but I am going to to boost my hair recovering after a second hairloss event.