As we age, there are 3 main reasons tear troughs form:

• Skin – the skin looses its elasticity Loss of Skin elasticity
• Volume loss – we lose our fat pads which usually  gives volume and support to the eye area.
• Skull changes – the eye socket becomes larger  and the cheekbone reduces in  size with less cushioning around the eye.

Other contributing factors include genetics, pigmentation, lack of sleep and lifestyle. As we mature in years the malar fat pad which is adjacent to the nose and below the eye shrinks and drops and this causes fat reduction under the eye, causing darkening in the area and a loss of volume.

The darkness under the eyes  is often caused by shadowing of the underlying muscle and blood vessels which shows through the semi-translucent skin