Instead, these are hair dyes uniquely formulated for graying and meant to return you to your previously natural color.

"I prefer permanent hair color because it provides long-lasting ... Every specialist we spoke to agreed that you should look for non-toxic products that do not include large (or any) amounts ...

Women who regularly use permanent hair ... regular use of the hair dye for at least 15 years were more than three times as likely to develop bladder cancer as non-dye users, concluded the study.