Wrinkling, loss of elasticity, laxity, and a rough-textured look are all signs of skin aging. This aging is accompanied by phenotypic changes in cutaneous cells, as well as structural and functional alterations in extracellular matrix components including collagen and elastin. Skin aging can be classified into three main categories: intrinsic (chronological), extrinsic (photoaging), and combined (intrinsic+extrinsic). Intrinsic aging occurs over time without any obvious cause; examples include thinning hair, decreased smell capacity, and increased wrinkling. Extrinsic aging results from the effects of environmental factors such as sunlight exposure that damage skin tissue causing age spots and wrinkles. Combined aging occurs when you get both intrinsic and extrinsic aging at once. Skin aging is primarily caused by genetic factors but also greatly affected by sun exposure, environment, lifestyle, and nutrition. Sunlight causes your skin to lose its natural moisture and increases your risk of developing skin cancers. Environment plays a role in determining your skin's fate: people who live in cold climates tend to have thinner skin than those who live in warmer climates. Lifestyle factors such as smoking, drinking too much alcohol, and using drugs such as cocaine will also increase your risk of getting skin diseases and disorders. Poor diet is another major factor in skin aging.