Hello dear,
Dont worry. The problem is not with your hair, its with the way you handle your hair.
Firstly i would suggest you to stop experimenting different shampoos.
Hairs are very delicate, cant tolerate a variety of products and specially the harsh ones.
You can use any mild shampoo as correctly prescribed by your doctor.
But for
dandruff, you need to use some anti dandruff shampoo.
I will recommend you Scalpe new shampoo to be used on alternate day basis fr 2 weeks , leave it on scalp for 3-5 minutes before you wash off your hair.
The only problem with these anti dandruff shampoos is that they make hair a little dry which is already your problem, but dear if you use conditioner afterwards, it will not trouble you.
And put hair oil only before you wash your hair, that too not for more than half an hour.
Hair oiling willl aggravate your dandruff.
I appreciate your dieting habits.
Keep it up.
Stay healthy.