Youthair is a hair colouring rejuvenator designed to blend away gray on a gradual basis. It comes in the form of a liquid and a cream. Youthair is mainly designed for men but it can also be used by women. Its main active ingredients are sulphur and lead acetate, working together to replace lost hair-pigment melanin with a similar acting agent - lead sulphide. Although there are unfounded claims that it is possible to restore gray hair using certain nutritional supplements, herbs, exotic oils or pills, such solutions are nothing but a waste of money. The only proven way to restore your natural hair colour at the moment is to get an external agent to replace the missing pigment in the fibre of your hair.
Youthair is an old traditional product that is in its composition very similar to Grecian formula and other lead acetate-based hair colorants. Lead acetate-related health issues have been discussed in more detail in the post "Is Grecian Formula Safe?".
Consumer reviews of Youthair are mixed but the majority of them are positive. This product seems to work well on fine hair that is lighter in colour but reviews from Afro-Americans seem to prove that it doesn't work on their hair. Some consumers were put off by what they consider to be bad odour. This is a common complaint with all products using sulphur. It is best advised, if possible, to try various hair colorants besides Youthair, for example Grecian formula, Restoria, GreyBan, etc., in order to find the product that suits you best. They all work in a similar fashion and, therefore, watch for differences in their secondary properties, such as ease of application, smell, greasiness and pricing.