To dye or not to dye?

As a teenager I loved to colour my hair. I have had almost every colour (at some point) apart from green & blue. I haven't coloured my hair for years now,
a) because its unusual to see people with hair my colour in this country
b) because I'm lazy
c) I hate the roots showing through. Ugh!

I read this blog post tonight and though it was worth reading and knowing about. My mum tells me this kind of stuff all the time, but then again while growing up she would say that chewing gum caused cancer and many other things that she felt were unhealthy and I should stay away from.
However, she might have a point about hair dye. Read it for yourself and decide.