Wrinkles
 A number of factors contribute to the formation of wrinkles.

Heredity
If you look at your parents and grandparents, you will have a good idea of the pattern of wrinkling you might expect to see in yourself.

Sun Damage
Collagen deterioration is accelerated by the sun's rays. The Ultraviolet B (UVB) rays and the longer Ultraviolet A (UVA) rays of the sun both penetrate into the dermis, causing the breakdown of collagen and the formation of wrinkles, as well as other signs of sun damage: dilated superficial blood vessels; pigment changes; and scaly patches.

Muscle Pull
Consistent tension in a particular area of the face due to a habitual facial expression can result in a permanent furrow Frown lines between the brows, fine lines around the eyes (better known as crow's feet), and smile lines extending between the nose and mouth are common examples of muscle pull furrows.

Sleep Creases: Vertical lines on the forehead and the cheeks can be caused by habitually pressing the face into a pillow night after night while sleeping. As the skin loses its elasticity it does not snap back in the morning and these lines become permanent.
Fat Loss and Redistribution : Loss of the fat cushion or redistribution of this cushion in the third layer of the skin often occurs in the fourth to sixth decade of life. A redraping of the skin results, with furrows and creases appearing on the forehead, around the eyes, and on the chin and neck. The pull of gravity also comes into play because in certain areas the skin lacks the cushion like support of the fat. The result is often a gaunt, wrinkled appearance. Sun damage clumps up the protein in the dermis, and with subsequent muscle pull, gravitational pull, sleep compression, fat loss and redistribution, the folds and creases take shape.

Gravity Changes
Young skin, because of its elasticity, can withstand gravitational pull. With age, degeneration of the collagen and elastin in the dermis makes the skin more susceptible to the pull of gravity causing it to sag. Droopy upper eyelids and bags under the eyes and jowls are common examples of the impact gravity can have on the face. The "mirror test" shows you how gravity may have affected your facial aging. Lying on your back, hold up a mirror and examine your wrinkles looking at the depth of creases and angles over the bones. Now, lay the mirror flat on the table and gaze down into it. You will notice that certain areas of your skin are looser than others.