If you want to turn your hair white, you can say "to whiten my hair". If you just want to change your hair to a lighter colour, you can say "to lighten my hair".

I think you want to say " to bleach/lighten my hair" which will make your hair lighter in color. If you really want to say, " to make my hair white", I would suggest "to whiten my hair."

I completely agree with Angela. While 'whiten' is OK grammatically, it's simply the wrong word for the context. To 'whiten' suggests that you are putting a white colour over something.- you might whiten your tennis shoes, but you would never usually whiten your hair. The only situation you might whiten your hair is if you are going to a costume party as an old person! Normally, you lighten or highlight your hair to make it slightly lighter, or bleach it to make it really light. Trust what the women tell you on this one! :)

US English - no. You can't "whiten" your hair. (Native speakers wouldn't use that term and people would be confused about what you meant). If you are making your hair a slightly lighter color than it is, you could say "I'm lightening my hair" or "I'm highlighting my hair." If you are making your hair blonde (or white), then you could say "I'm bleaching my hair." ----------- P.S. There is an idiom that "______________ turned my hair white" or "_____________ gave me white/grey hair" when something is very scary or stressful. Even then, though, we wouldn't say "whitened." It's just not the right word.

'to whiten my hair' is the proper way to say.