Smoking and stained nails

Congratulations on quitting. A nail grows from the cuticle and is actually clean so if nothing works immediately nature should do its part.

I agree with "tiptopmanager" that you can use lemon juice - but use hot water and add some lemon juice to the water and soak your nails in it for some minutes. After this it is important to rub your nails and nailroots with oil (oliveoil works great) to ensure that your nailroots are not dried out.

All the answers are correct. Tobacco stains can be removed with everything from lemon juice to bleach. The safest and healthiest way to get rid of the stains is let the nails grow out as the new portions will not be stained. If you have stains on your fingers as well (common with cigarette smokers), you can also use an exfolient. The reason that cigar bands were placed on cigars is so that the aristrocrats would not have tobacco stains after smoking a cigar. They would hold the cigar through the band and only smoke it up until they reached the bands. The cigar band was created for women as the queens would smoke cigars and did not want their fingers stained.