Dark circles can appear for a variety of reasons, including genetics, ageing, allergies and lifestyle factors. In some cases, the tiny blood vessels under the skin become dilated or the skin becomes inflamed, which can make the circles more visible. This is especially common in people with allergies.
As we age, the natural fat padding beneath the eyes gradually thins. Without that cushioning, the under-eye area can look more hollow, allowing shadows to form more easily. This loss of volume makes dark circles more noticeable.
For many people, dark circles are also hereditary, so if your parents have them, you’re more likely to develop them too. Over time, sun exposure and natural skin ageing can also cause increased pigmentation, which can make the under-eye area appear darker, even if the skin is otherwise healthy.