Aging has many effects on a person’s skin, from wrinkles and sags to increased risk of certain skin conditions, such as skin cancer. As people age, their skin begins to change due to environmental factors, genetic makeup, nutrition and other factors.

Covering the entire outside of the body, the skin is the body’s largest organ and consists of three layers: the epidermis (composed of skin cells, pigment and protein), the dermis (composed of blood vessels, nerves, hair follicles and oil glands) and the subcutaneous tissue (composed of sweat glands, hair follicles, blood vessels and fat). Each layer also contains connective tissue, collagen fibers for support and elastin fibers to provide flexibility.

Hair and nails are modified versions of skin. Hair maintains warmth in the body by preserving heat. Hair located around the eyes and in the nose and ears protects these areas from small particles such as dust. It also cushions the body against injury. Nails sprout from deep folds in the fingers and toes. They provide protection and support for the sensitive fingertips and toes.

The skin serves many roles in an individual's body. It protects a person from the environment, helps maintain fluid and electrolyte balance and provides receptors that help the body feel sensations such as pain, vibration and pressure. It grows faster than any other organ in the body, and people continuously renew their skin throughout their lifetime.

From the moment a person is born, the skin begins a process of constant change. A baby’s skin tends to be soft and smooth and has a thicker layer of fat and thinner layer of keratin, a protein that is the chief component of hair and nails. As a person enters the young adult years, the skin becomes stronger and suppler.