Dark circles are one of the most prolific skin concerns across all ages, and reasons range from alcohol to hormones to lack of sleep and genetics.“Dark circles are slightly misleading because they are not really one condition,” says Dr David Jack, an aesthetic doctor based in London’s Harley Street. “What we perceive as darkness underneath the eyes can come from increased melanin in the skin, visible blood vessels through very thin eyelid skin, changes in the underlying anatomy that create shadow, or a mixture of all three.”The colour can offer some indication of the cause. Jack says brownish circles are more suggestive of pigmentation, while blue, purple or reddish tones can indicate a greater vascular component.If you find that darkness noticeably changes according to the direction of the light, then facial structure and shadow may be the cause.So before investing in another concealer, here is what you can do to make dark circles under the eye less noticeable without make-up – or a syringe.1. Choose your eye cream according to the causeRetinoids may be particularly useful for thin-looking skin – or for people who are older. Photo: ShutterstockWhile they may look the same, not all dark circles respond to the same skincare.