Can you tell me what exactly constitutes under-eye bags? Under-eye bags are caused by the protrusion of fat from the lower eyelid through a weak fat lattice, accompanied by skin laxity, resulting in a bloated bulge and sagging skin under the lower eye area. Generally speaking, under-eye bags are more common in middle and old age, and there is a genetic factor for the appearance of under-eye bags in young people. With bags under the eyes, a person’s face appears to be aging. The cause of under-eye bags is traditionally thought to be the protrusion of orbital fat caused by the accumulation of fat in the lower eyelid skin, but now there is a new understanding that under-eye bags are a disruption of the balance between the amount of fat in the orbit and the supporting structure of the lower eyelid, that is, as people age, the soft tissue of the skin relaxes and the balance is broken after the fat.