Functional foods are defined as products that go beyond basic nutrition to provide proven effects on improving health or reducing the risk of disease. This concept was shaped in its modern sense by Japan's pioneering FOSHU (Foods for Specified Health Uses) system in the 1980s. Today, it is studied through a wide range of bioactive components such as probiotics, polyphenols, omega-3 fatty acids, dietary fibers, and plant sterols.

Although regulatory approaches in this field vary from region to region, as seen in the examples of the European Union, the USA, and Turkiye, the common point is the requirement that health claims be based on scientific evidence. Among the most significant challenges facing functional foods are consumer acceptance, market dynamics, and issues such as the bioavailability of these components. This field continues to evolve rapidly with promising trends such as personalized nutrition, nanotechnology applications, and a shift toward sustainable bioresources.