Description: An organic hair dye derived from plants, it enriches the depth of your own color.
Hair type(s) it's best for: Hair that is nonfrizzy and "virgin" (untouched by chemical processes).
Touch-up time: Retouch every four to six weeks. The color lasts until it is cut off. Henna makes hair resistant to other chemical treatments, which means you can't try to color over the henna with regular coloring agents.
Damage level: Coats hair shaft and does not allow it to breathe, which can cause hair to loose elasticity.
Hair-care-adjustment: Since henna makes hair prone to snapping and breaking, style with care and keep well moisturized.
Process: Semi-permanent color
Definition: Coats the hair, depositing color without completely opening the hair cuticle.
Hair type(s) it's best for: Excellent for fine hair because it only deposits color and gives hair more body. Best option for permed hair, since it is less damaging than permanent color.
Touch-up time: Approximately four to six shampoos. Damage level: Has no ammonia or peroxide, so no damage to hair.
Hair-care adjustment: Color-enhancing shampoos can help the color last, but this is not recommended for women who have both color and a perm; they would be better served with a moisturizing shampoo and conditioner.
Process: Demi-permanent color
Description: Ammonia-based color mixed with low amounts of peroxide. Cannot dramatically lighten hair color.
Hair type(s) it's best for: Can be used in conjunction with other chemical procedures such as relaxers or perms, but you must wait at least two weeks between procedures. Also good for covering gray, especially if hair has also been relaxed or permed.
Touch-up time: Approximately 24 shampoos.
Damage level: Minimal damage to hair if it is only color, more if hair must be stripped first (see Blonding). Hair-care adjustment: Use shampoos for color-treated hair and leave-in conditioner; condition every time you wash. If you heat-style your hair, include a regular deep conditioning treatment in your regimen one to two times per month.
Process: Permanent color
Description: Deposits pigment in hair shaft, penetrating hair cuticle. The only option for dramatically changing hair color; necessary if you want to go blond.
Hair type(s) it's best for: Hair that has no other chemical processes in it. This is the process that most effectively covers gray hair. If you have a perm, permanent color can be done, but it must be done with caution. It's also a good option for fine, thin hair, since the procedure lifts the hair cuticle, expanding the hair and making it easier to style.
Touch-up time: Retouch every four to six weeks. The color lasts until it is cut off.
Damage level: More damage is done if hair must be stripped first (see Blonding).
Hair-care adjustment: Use gentle, moisturizing shampoos and conditioners for color-treated hair. Condition every time you wash. If you also heat-style your hair, incorporate a regular deep-conditioning treatment into your regimen two to three times a month.
Description: Hair strands are stripped of natural color. Can be an effective alternative to overall blonding, or a blending, minimizing method for gray hair. Permanent hair color is applied in certain areas allover the hair using different techniques.
Hair type(s) it's best for: Can be done on hair that has been chemically treated, but the hair must be healthy and well conditioned.
Touch-up time: Touch-ups can stretch from two to three months, since the roots are less obvious.
Damage level: Depends on what types of highlights are done. Those with peroxide or ammonia in the formula are harsher.
Hair-care adjustment: Dryness may be noticeable on highlighted parts. Use moisturizing hairdressing cream on those areas or on ends.
Description: Natural hair color is stripped away using peroxide. A permanent, lighter hair color is then applied to replace it.
Hair type(s) it's best for: Natural, healthy hair that has had no other chemical treatments. It can be used on permed hair, but most hairstylists advise against it.
Touch-up time: Until it grows or is cut out. Touch-ups should be done every four to six weeks on roots only.
Damage level: Very high. This is double-processed hair.
Hair-care adjustment: Return to salon for follow-up moisturizing and protein treatments. In addition to the appropriate moisturizing products, a deep-conditioning treatment must be incorporated into the regular hair-care routine.