The acidic, anti-bacterial and antiseptic properties in some vegetables and fruits allow them to lighten the skin naturally. Potatoes, cucumbers and lemons are three that can help eliminate dark skin under the arms.
Potato - Thinly slice a potato and rub a slice on the dark area. Or, you can grate some of the potato to release the "juice." Apply this juice to your underarms, let it dry 10 minutes and rinse.
Cucumber - Just as you did with the potato, you can rub cucumber slices on the affected area or grate some of the cucumber and use the juice. You can go a step further and add a few drops of lemon juice and some turmeric (enough to make a paste) to the cucumber juice..... click on link to see more
