Your best bet here is to exfoliate the skin...GENTLY to remove the dead skin cells that are most likely causing the discoloration. Do this once week and apply cocoa butter to help new skin cells grow. Emu oil may also be of help. If the discoloration persists, take a look at the deodorant you wear. If it contains aluminum it can cause the discoloration in both areas as it attempts to leach out of the body. Find a deodorant that is natural and does not contain aluminum.
If discontinuing your deodorant does not work, then you should seek the counsel of a natural health specialist as soon as possible to rule out liver and/or kidney problems as both of these can cause discoloration of the skin. Drink plenty of water to help flush out your system. And load up on antioxidants by drinking several cups of green tea daily and taking extra vitamin C, grapeseed extract, and CoQ10.
It is normal for some difference in skin color in various areas of the body, but it is important to rule out any factors that might be causing it. The skin is the largest organ of the body and therefore is our greatest indicator of general health.
answered by R P