When my Dad died in June he was looking pretty sparse. Totally gone up front up to just before the curve of the top of his head. What was up there was whispy and white. He brushed this over to create semblance of hair on top. Behind this area was a bald spot that had some hair left still on it, but just a thin "film".
Grandfather died with more hair than my dad, but both were nonexistent from the front up to the top, and then thin.
I have been following their progress by old photos and asking relatives how old they were at the time. By my age, they'd both lost a couple inches off the front. My dad had lost that couple inches and begun to noticeably thin on top. It seems they both started the process around age 25 and by 30 were at this stage.
I too started the process at age 25 and have not lost a single inch on my hairline. Via the various treatments I've pretty much maintained my hairline completely, although as you can see from the pics I posted, there is some thinning. That was my goal and so far I've succeeded without Rogaine or anything other than DHT inhibitors.
While I don't know exactly how far I would have progressed without treatments, I know 100% for sure that it was going, and going fast, five years ago. I really believe a big help for me was Nizoral. I had such severe irritation and itching and redness on my scalp that my hair was falling out like mad from it. Controlling this alone helped 80% for me. I know for a fact neither my dad nor my grandfather had any idea that doing so might help, and I know for a fact both of them had this same problem. So im a big proponent of the logic that inflammation plays a huge role in speeding up the process of hair loss.
Im remote right now so I don't have photos I can post, but if this thread is still alive when I get home, ill do so.
HairLossTalk.com