oiliness

Oiliness is the quality of being oily or containing oil. It can describe natural secretions, such as sebum produced by sebaceous glands in the skin, the fatty mouthfeel of foods, or the greasy feel of surfaces contaminated with oils. The concept is used in dermatology, food science, and materials science to characterize lipids, greasiness, and related sensations or properties.

Skin and scalp oiliness results from sebaceous gland activity. It is influenced by genetics, hormones (notably androgens), age, climate, and skincare practices. Excessive oiliness can contribute to shiny skin, enlarged pores, and acne, while too little oil can cause dryness. Management includes regular cleansing with mild cleansers, noncomedogenic moisturizers, and targeted therapies (salicylic acid, benzoyl peroxide, retinoids) when necessary. Overwashing can worsen dryness and stimulate more oil production in some individuals.

In foods, oiliness describes the perception of a fatty or greasy mouthfeel, linked to lipid content, emulsions, and oil release during chewing. It can be desirable in some products, such as pastries or fried foods, and undesirable in others, such as lean meats or low-fat products. Techniques such as adjusting fat composition, emulsification, and cooling influence perceived oiliness.

Oiliness also refers to surfaces bearing oil residues, which can affect friction, slip, cleanliness, and safety. In manufacturing and maintenance, oiliness levels are assessed to control lubrication, contamination, and product quality.

Oiliness is not a disease but a trait or property that can have practical implications in cosmetics, nutrition, and industry. It is often measured qualitatively by sensory panels or quantitatively through sebum secretion rates, oil contact measurements, or surface energy analyses.