Dark circles under the eyes are a common concern that can make the face appear tired or aged. They can be caused by a variety of factors including genetics, lack of sleep, dehydration, allergies, and thinning skin that reveals underlying blood vessels. As we age, the loss of collagen and volume can make dark circles more noticeable. Lifestyle factors such as screen time, smoking, and sun exposure can also contribute. Understanding the root causes of dark circles is the first step toward finding effective treatments and restoring a brighter, more refreshed appearance.