As a result of the sustainable use of agricultural wastes and by-products, the dependent industrial sector may earn additional income by producing value-added products. Furthermore, effective valorization of wastes/by-products can decrease unwarranted pollution, reducing environmental stress. A bioactive compound is one that has biological or physiological actions on living tissues such as phenolic acids, flavonoids, lignin, terpenoids, for instance, carotenoids and essential oils, bioactive peptides, and glucans. These compounds are generally of great interest in various industrial sectors because they are antioxidants, antimicrobials, promote the immune system, as well as modulate the intestinal microbiota. Bioactives found in plants, animals, and marine wastes and by-products are reviewed in this study, highlighting the use of food wastes and by-products, with an emphasis on their potential uses. The term “bioactive compounds” refers to substances present in small amounts in foods that are beneficial to health. This study aims to discuss the conversion of food waste into bioactive compounds and alleviate food insecurity to enhance health.