**6. Structure of aged skin**

The process of skin aging results in the following histological changes.


The total of these various changes causes an increase in the fragility of the skin, a decrease in the exchange of nutrients between the dermis and the epidermis (avascular layer), and alterations in the healing process. It also decreases the number and diameter of collagen fiber bundles, appears a disorganized collagen, and increases the proportion of collagen type III versus collagen type I.

There is a general thinning of the skin and a weakening of its adipose-muscular support to which the physiological bone resorption that appears in the aging process must be added. This loss of skin tissue, especially dermal and hypodermic, favors the appearance of visible signs of aging, such as wrinkles [9].
