Yellowish fingernails because of excessive wearing of nail polish.

photo from www.modernhandreadingforum.com

Article from:  Kristie Leong M.D.

If you constantly wear nail polish, you may be depriving your nails of the oxygen they need to maintain a natural color. Yellow fingernails can be the result. One solution is to let your nails go natural periodically instead of covering them with polish. Another option is to apply a clear base coat before applying your chosen nail polish. This appears to reduce the incidence of yellow fingernails. These are some simple steps you can take to get rid of yellow fingernails, although it's important to understand the underlying cause before using cosmetic methods to reduce their appearance. If there's any doubt as to the cause of your own fingernails, see your doctor for evaluation and reassurance.