Under eyes puffiness is part of the normal ageing process.
With ageing the fat pad under the eyes tends to migrate downwards causing bulging and puffiness, through the very thin skin under the eyes.
Lack of sleep, smoking and fluid retention can exacerbate the appearance.
Dark circles under the eyes also tend to appear with ageing.
Their etiology is multifactorial, including genetic and ethnic factors, poor sleep, poor diet, allergies, hyperpigmentation, smoking, anemia, unprotected sun exposure and thyroid disease.