I met my husband the first week of college - I did not have a single grey hair. 3 months later I had several all at the crown. We've been married for 42 years and it is a long running joke in our lives - even he will confirm that it is true.
I have colored my hair occasionally - mostly when looking for a job. It is very fine, rather thin and grows very quickly. For a few years in my early thirties I had a clump of white hair in one spot and I half heartedly kept it colored or I looked lopsided. Haven't colored it since the early eighties and won't start now. Way too much trouble for me. I have a friend who is an unnatural blonde has been dying her hair for so long that she doesn't even know what her natural color might be anymore.