The gel could potentially impact on
the colour due to the pH level. Generally, hair care
products that are designed to not affect colour are Acidic, around pH
of 4. We have tried to keep our products pH neutral (around 6.5 for the Gel)
so they are non-irritating, as acidic products that are left on (like
the Gel is) can be irritating to the scalp if you're already suffer
from any irritation or dryness.