Skin care or skincare is the practice of maintaining and improving the health and appearance of the skin. It includes washing, moisturizing, protecting from the sun, and treating skin problems like acne and dryness. Skin care can help prevent infections and irritation and is an important part of daily hygiene.

Skin care is at the interface of cosmetics and dermatology. Skin care differs from dermatology by its inclusion of non-physician professionals, such as estheticians and nursing staff. Skin care includes modifications of individual behavior and of environmental and working conditions. Skin care is an essential part of wound healing, radiation therapy, and the management of some medications.

The skin is the largest organ in the human body. It protects against germs, dirt, and harmful substances. Simple habits like washing and applying lotion can make a big difference in skin health, but little is known scientifically about the benefits and clinical efficacy of these practices. Skin care routines, even in hospitals and medical facilities, are often based on personal beliefs, preferences, and local circumstances rather than current evidence or best practices.

Taking care of one's overall health improves one's skin, such as attention to diet and lifestyle. Oxidative stress is widely recognized as a contributing factor to skin aging. Drinking enough water may help to keep skin hydrated, especially in individuals who are chronically dehydrated. A poor diet lacking vitamins can lead to skin problems, such as scurvy, pellagra, and numerous subclinical pathologies that have not been studied in detail. Lack of sleep has been shown to make conditions like atopic dermatitis, eczema and psoriasis worse, and these conditions have in turn been shown to reduce sleep quality.

Skin care products help clean, protect, and improve the skin. In the U.S., the Federal Food, Drug, and Cosmetic Act groups these products into two main categories: cosmetics and drugs. Drugs must go through a strict approval process before they can be sold. Cosmetics, on the other hand, do not need FDA approval before being sold, though they are still regulated. Cosmetics are used to cleanse or enhance appearance, like face washes and moisturizers. Medications are meant to treat or prevent health issues, such as acne creams or sunscreen. Some products, like dandruff shampoos and moisturizing sunscreens, fit into both categories. Cosmeceuticals, although not officially recognized by the FDA, combine cosmetics with "biologically active ingredients" that may have health benefits. Nutricosmetics are products taken by mouth instead of being applied to the skin.

Here are some common ingredients and what they do:

The labels on cleansing and skin care products can be confusing because they use unclear words like "mild" or "gentle". This makes it hard to know how well a product works or what it actually does. Just because a product has a certain ingredient doesn't mean it is effective—how well it works depends on the whole formula and how it is used. People often mix up what a product does (like moisturizing) with what an ingredient does (like glycerin keeping moisture in or petrolatum protecting the skin).

Skin care interventions consist of applying one or more products to specific areas of the skin in a specific order. A skin care routine may consist of the following steps: