How do you slow down gray hair from growing too much?

I've read theres a vitamin that slows down the growing of grey hairs but I don't recall, is there anything besides coloring every 2 weeks or so.?How do you slow down gray hair from growing too much?
its all in the genes.if your parents got grey hair young,you probably; will too.so its coloring every 6 or so weeks is really your only choice.or you could go bald.