Demi-permanent hair color is ammonia-free, slightly alters hair tone, and lasts between five to 12 washes. Unlike ...

No more hair dye? Scientists think that may be what the future holds.

Herbatint $17, at select Whole Foods markets This plant-based product lets you achieve rich color without ammonia or peroxide. L'Oreal Couleur Experte Express $10, drugstore.com This kit is a great, ...

Natural and subtle.

Zhaoming says to monitor how often you dye your hair carefully. “My advice is not to dye your hair more than once every three months, or no more than four times a year,” she says. “Reducing the ...