You can get 3 or 4 levels of lift with 40 volume peroxide. Note though, that if you're starting at a level 2, that will bring you up to a 5, and maybe a 6 if you have fine hair. This level of hair colour is actually not really all that light. A medium brown or some might say light brown at best. Is this worth the damage you are going to do to your hair? Plus, the underlying pigment that will be left in your hair is going to be a bold orange as mentioned. If you choose to use colour, you MUST pick an ash tone to get enough drabbing to counteract all that orange. The results will still be a warm brown. Getting an ash result on that kind of lift at that level is not possible with store bought colours.
If you are concerned about the condition because you like having long hair, I would say don't do it!!! Highlights might be a better option so you can at least maintain some kind of healthy hair. Hair colour can be less damaging than bleach, but it's still damaging.
Have you considered Henna? After years in the hair colour industry, and all the horror stories of henna, I did some research and found out true real henna is actually amazing and healthy. (there are hennas out there that are combined with mineral salts that ARE actually terrible and can turn your hair green/black)
Henna can offer a beautiful auburn sheen to your dark hair and make your hair stronger.
Last edited by SusieSuze; 08-02-2011 at 10:49 AM.