That's a great question and I will attempt to treat it in depth because the categorization of hair as "dependent" does not appear to square with the fibrosis theory of baldness which is probably the best one that we have currently. It also implies to young guys, "why bother with minoxidil since my hair is going to become dependent on it". That's simply not how it works. Minoxidil works in a way that we continue not to understand but I don't believe that anyone believes that it makes hair loss or male pattern baldness worse. It simply recognizes that untreated hair in a person susceptible to hair loss is likely to be at risk of falling. The same goes with finasteride.
The prevailing fibrosis theory is almost sort of spooky like Schrodinger's cat in that the falling hair appears to fail before the blood supply to it is completely diminished. So merely adding in increased blood supply doesn't appear to resolve the issue. Finasteride and dutasteride can all but halt the progression of baldness but at least in those whose baldness is say more than a couple of years running, reductase inhibitors cannot "regrow" hair, only estrogen accompanied by higher body estradiol levels appears able to "regrow" hair.
We don't even have a running definition to my knowledge as to what constitutes the terms "growth" or "regrowth" or "improvement". Are there actually dormant follicles that are now growing? Is a longer period of anagen "regrowth" or just "growth" and all of this makes a difference. The one thing that I strongly promote and believe in is that hair has to be looked at in a holistic fashion. What this means to me is that the goal is not simply growth or regrowth or increased anagen, although we want all three. The real issue is why do some people have "nicer" hair, whatever that means, compared to others. So a lot of us XY's are hankering just as much for our "nice" pubertal hair as we are for any sort of coverage in general. So in my view, the question as re-stated is not so much how do we cure baldness.
It is rather, why can't we do anything to improve the quality of scalp follicles from the inside? This would include hairs that no longer become terminal or curly or kinked hairs on the scalp of a person with straight hair. In essence, we can no more resolve frizziness in a hair follicle than we can resolve dormancy of the follicle itself. Yes, we have marginal salon treatments that coat hair but nothing that improves the niceness and smoothness and sheen and manageability in groups which have straight hair. So, virtually always we can see a period of decline of the quality of hair in general before actual baldness becomes apparent. I can see it in my old pics and this period of declining quality can proceed down to the point where there are no longer terminal hairs being produced.
This is a complicated topic and to me a fascinating one. A great place to start is here:
Does scalp tension cause hair loss? Sixty years ago, researchers abandoned the scalp tightness-Androgenetic Alopecia theory. Now they're reevaluating it. Here's why.
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