An effective preventive measure for this kind of discoloration is to avoid wearing polyester underwear, which can cause perspiration to fester in that area. Change to pure cotton underwear. You can apply a few drops of lime or lemon juice to the dark skin to lighten it. You can also cover the area with yogurt and leave on for about 20 minutes before a bath for lightening the skin.
However, this remedy would have be continued for at least a month before you notice a visible change. You can also cut an orange into two and rub the halves on each thigh for a good 20 minutes. This will also have to be done over a prolonged period before you notice a change. Dried and powdered orange peels mixed with yogurt will also help sloughing off dead skin cells in that area. A cup of oatmeal in a cup of yogurt will also help lighten the skin. For daily maintenance of the area, make sure you keep it dry at all times. Use corn starch to ensure that there is no leftover moisture after you bathe.
If your thighs rub against each other while walking, then you need to lost weight on your legs, because this friction also causes darkness of skin.
answered by G M