**Abstract**

Functional foods are the foods claimed that have additional health benefits beyond their basic nutritional values, and functional food components are bioactive, potentially beneficial compounds that are found either naturally in foods or added to them as functional ingredients. Some important functional food components are carotenoids, isothiocyanates, soluble and insoluble dietary fiber, phenolic acids, fatty acids, plant stanols and sterols, flavonoids, polyols, soy protein, prebiotics and probiotics, phytoestrogens, vitamins, and minerals. Most of the functional food components occur mainly in plant foods (whole grains, fruits, and vegetables), however, few functional foods components, such as omega-3, -6, and -9 polyunsaturated fatty acids are also found in animal products (e.g. milk, fermented milk products, and cold-water fish). Evidence suggested that there is a relationship between functional food components and health benefits. Functional food components can be used for the treatment and prevention of different diseases. Biologically active functional food components can reduce the risk of certain non-communicable diseases, such as cancer, type II diabetes, cardiovascular diseases, osteoporosis, inflammation, and lowering of blood cholesterol. Thus, people should consume a wide variety of foods to assure the ingestion of functional food components in their body, such as fatty acids, fiber, carotenoids, flavonoids, prebiotics and probiotics, vitamins, and mineral.

**Keywords:** functional food, components, nutritional, physiological
