Dark circles under your eyes are caused by tiny veins that exist in that area. the skin is thin and sensitive under the eye and depending on the amt of veins you have, they can show up as dark circles. i have them, they aren't very dark, but they are definately noticeable - i really like them for some reason.
Don't think you can actually get rid of them - many eye creams promise to do this but very rarely do beauty products live up to their promises. Maybe stop bleaching your skin? or use an under eye concealor to mask it if it bothers you. also, make sure to use specific products for under your eyes - as that area is the most sensitive.
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