Genetics – There are people who naturally have darker circles under their eyes. Dark circles can be an inherited trait seen early in childhood. Having anemia can cause your skin to be paler than usual, dark circles can appear under your eyes.

Fatigue – As for others, their dark circles could be caused by lack of sleep. Your skin can become dull and paler if you are having sleep deprivation, which turns the dark tissues and blood vessels beneath your skin to be more visible.

Age – The reason for ageing to be one of the factors of black circle is the same as how fatigue can cause dark circle formation, as people get older, their skin becomes thinner. 

Eyestrain – Staring at electronic devices may cause strain on your eyes, which can enlarge the blood vessels around your eyes.

Dehydration – When your body is not well hydrated, because the eyes’ close proximity to the underlying bone, your under eye skin starts to look dull and eyes become sunken.

Sun Damage – Your body produces an excess pigment that gives you skin colour under the sun exposure. Overexposure to the sun can lead to pigmentation in the surrounding skin to darken.