The skin around the eyes is the thinnest and most delicate, and as result, tends to be more susceptible and noticeable to the visual signs of aging.

As men get older, their skin loses collagen, becoming thinner and more translucent. Aging changes in the skin cause the eyelid skin to lose elasticity and sag. As the eyelid begins to loosen, normal fat that lies beneath the eyeball pushes forward against the lower eyelid and creates a bulge or eye bag or puffy eye. A shadow forms beneath the protruding puffy eyelid and creates a dark circle beneath the lower eyelid. Circles may also gradually begin to appear darker in one eye than the other as a result of some habitual facial expressions, such as an uneven smile.

Additional causes for dark circles and puffiness under the eyes are genetic or medically based, such as infection, head or facial trauma, and others are lifestyle- based, such as drinking too much coffee or crying. Periorbital Hyperpigmentation, the official name for when there is more melanin produced around the eyes than is usual, also gives the skin under the eyes a darker color.