The primary purpose of food was initially to provide essential nutrition for human beings to sustain their daily activities. However, due to dietary habits and lifestyle changes, food has now emerged as a trigger for lifestyle-related diseases, such as obesity, high blood pressure, and diabetes. For prevention of the lifestyle-related diseases, it is necessary to improve the eating habits, furthermore, the prevention is possible by the intake of "functional foods". By incorporating functional foods into one's diet, it is possible to enhance overall health and minimize the risk of developing lifestyle-related diseases. Functional ingredients refer to food products that have the same appearance as traditional foods found in our daily diet. However, what sets them apart is their ability to provide physiological benefits and potentially lower the risk of noncommunicable diseases. According to the American Dietetic Association (ADA), all food can be considered functional to some extent when viewed at a physiological level. The ADA emphasizes that the term "functional food" should not be used to categorize foods as either good or bad. Instead, they recommend that all foods can be part of a healthy eating plan as long as moderation and variety are maintained.

Functional ingredients encompass a wide range of compounds that have been associated with various health benefits. Some examples of these compounds include allyl compounds found in garlic, carotenoids and flavonoids present in fruits and vegetables, glucosinolates found in cruciferous vegetables, hypericin and pseudohypericin found in St. John's wort. Additionally, functional ingredients include peptides such as epidermal growth factor, opioid peptides, and lactoferrin, which are found in milk. Furthermore, arachidonic and docosahexaenoic acids are examples of functional ingredients derived from human milk and obtained for use in infant formulas from diverse sources such as algae, bacteria, and fish.