There are several reasons why your armpits and your genital area, have become so dark, in spite of you being fair. If you sweat profusely, if you generally wear polyester clothes, if you use deodorants that don't suit your skin, or if you use razors or hair-removing lotions to remove hair from both these areas, then your condition can be linked to one of these causes. All or any one of these could be the reason for your skin turning dark. And chances are that these areas have become dark over a period of time.
The first thing that you need to do is start wearing cotton dresses, as well as cotton undergarments, to absorb the sweat. The uric acid that is released along with the sweat is what causes the skin to darken, if left unattended. Shaving and using hair-removing lotion is also an absolute no-no for these areas. Shaving causes a lot of friction and hair-removing lotions contain strong chemicals to dissolve the hair. This inevitably affects the skin when used over a period of time. Also, use a non-acidic soap or a herbal soap for your daily bath. Even this small change will help.
There are a few remedies that you can try in order to reduce the darkness in these areas, but be forewarned, these remedies will take time to show any results. Both these areas are very sensitive, so the treatment administered to them has to be mild enough so as to not cause any kind of aggravation and discomfort. One of the best remedies for dark skin is to rub a piece of lemon on the affected area. But because these areas are sensitive, it would be advisable to mix lemon juice with other ingredients to benefit from the natural bleaching properties of lemon. You can mix lemon juice to turmeric and cucumber juice and apply this mixture to the affected areas. Leave it one for at least 15-20 minutes before washing it off with warm water. Alternately, you can mix lemon juice with yogurt and apply it regularly to both the areas.
Another mixture that helps considerably is two tablespoons of finely powdered dried orange peels mixed with one tablespoon of yogurt. You can also use a paste made out of sandalwood and rose water. One more concoction that you can apply is a mixture of honey, almond oil, lemon juice, and milk powder. Apart from removing the darkness, this mixture will also help to naturally moisturize these areas. Last, but not the least, as it is highly effective, apply aloe vera gel to the affected areas regularly.
answered by G M