Let's be honest, most of us have some kind of color treatment done to our hair. But even if you do not, this still applies to you! Here's why...
Your hair color is effected by many factors, hard water, salt water, chlorine from swimming pools, heat styling, the sun... All of these cause fading, brassiness, dullness and even tinting your hair green (chlorine!)
There are two ways to go about choosing the appropriate color-depositing products. Are you looking to add color or balance / correct color.
Adding color, for example, would be ideal for a redhead. Red haircolor fades the fastest. Using red-depositing products adds vibrancy and depth back to your hair.
Color balancing or correcting is most common. Remember when you'd see grandmothers with lavender hair? Well grandma was on to something. As her hair was turning white or grey, it was also beginning to yellow. Using a purple shampoo or conditioner can cancel the yellow and brighten not only white and grey hair but also blonde. (If you overuse, this could lead to that lavender tint...maybe you like that?) Maybe you've had beautiful ombre or balayage color. Well if your ends are now brassy or orange, try a blue color-depositing shampoo and conditioner. This will cancel the orange and you'll regain those honey or beige ends again.