Prolonged use of the nail polish can cause nail yellowing. You can solve this problem very simple, appealing to an ingredient found in any home. This is toothpaste. Apply it on the nails, then lightly scrub them using a toothbrush.
Let the toothpaste act for 5 minutes, then rinse thoroughly. Repeat this treatment 2 times a week and you will notice that your nails will become white and shiny.
See a video demonstration below: