I noticed regrowth after 2 months. I also upped the intake of vegetable silica in my diet SIGNIFICANTLY and noticed a further acceleration of hair regrowth. So, it's not just the gel itself, but a diet EXCEPTIONALLY high in silica.
I think I keep Cost Co. in business eating their baby spinach like it's going out of style. It's just the most easily digestible form of silica compared to the 'wholegrain' sources of the trace mineral.