Tear troughs can be caused by congenital thin skin under the eyes, aging, long-term UV exposure, late nights, excessive weight loss, and so on.
Tear troughs are generally congenital, mainly because the soft tissues under the orbital septum tend to atrophy, and there may also be sagging, leading to tear trough symptoms.
In most people, the tear trough is not obvious when they are young, because when they are young, subcutaneous fat is abundant, and the skin is in a taut state, with only a shallow outline of the tear trough. However, as we age, the subcutaneous fat shrinks and the skin sags due to loss of elasticity, and the tear trough on the inside of the lower eyelid becomes visible.
Tear troughs can be deepened by staying up late, excessive weight loss and long-term ultraviolet radiation.