What causes Dark Undereye Circles?

There can be one or several reasons together which may contribute to a darkened or sunken look. These include a lack of sleep, iron or other vitamin deficiencies, sickness (sinus infections in particular), hyperpigmentation, excessive vascularization (due to medications such as Retin A), visible blood vessels due to fast loss, thin, aging skin or hereditary thinness or superficial vessels and fat loss in general which causes a sunken look.

In general temporary dark under eye circles may indicate a state of poor health or exhaustion. More persistent under eye circles (undereye) are more likely the result of genetic tendencies such as hyperpigmentation as is often seen in ethnic persons such as persons of Indian decent. Hyperpigmentation or excessive vascularization (due to medications such as Retin A): Many times when this is the case, vessels can be removed or "zapped" using various lasers or even intense pulsed light. Visible blood vessels due to fast loss, thin, aging skin or hereditary thinness or superficial vessels may be the culprit. You want to be careful not use a fade cream like hydroquinone if this is the case...

The facial fat loss we experience due to aging can significantly increase the sunken look. In the highly vascular area of the under eye area, the blood vessels are more visible. Fat loss in general can cause a sunken or hollow look. In the case of chronic under eye circles, this is likely the culprit.
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