Well Bryan,
I'm not Armando or another person.
My poor English don't help me...
So, the dry skin or hair is a problem which develop after puberty, it's no doubt...
The children have moisturized hair and beaoutifoul skin but the hair is very thin and clueless.
Have you ever view a man or a woman without hair's problems? The hairs is more more thicker than they was children... the same is the skin.
So, Dutas could caused a brutal change in sebaceous glands and an excessive dry is a temporaney syntom of this new hormonale situation in the gland.
What do you think about the dry hair, skin ecc.. that SOME PEOPLE have with high dosage of dutas?
Some people used Duta to acne problem with great results in Italian sites...
Often during the develop of the body the hair change colour and structure and this maybe is an effect of hormones that stimulating more or less sebaceous glands, melanocities,keratinocities ecc..
Children have hair lighter than adults.
Often the patients who takes "Roaccutan" that reduces the dimesion of sebaceous gland, says that his skin and hair became more more dry!!!!!
The dry skin and hair is often a genetic problem (less activity of the glands) and the Dutas could exasperate this condition because DHT stimulate the sebaceous glands...
In conclusion I don't think absolutely that the sebum plays a role in GROWTH of hair, but in the texture and in quality of hair and in the protection of the skin but is very important a right dose of sebum...
Why "mother nature" give us sebum

?
Sorry for my English
Bye