Gray hair can turn yellow as residue that is left on your hair from other products can make hair look brassy and dull. Products such as shampoo, conditioners, hair spray, mousse, and gels can leave a residue on the hair shaft that actually yellows.
Yellow hair can also be caused as your hair picks up particles from the environment. Chlorine, minerals and other chemical residues in water, sunlight, and even oils from your scalp can also give gray, silver and white hair a yellowish or brassy look.
Vitamins that are high in beta carotene and some medication can cause some yellowing. This gray hair shampoo gently removes the yellowing buildup residue from your hair to reveal radiant healthy fuller hair that is more manageable and softer.