Edible seaweeds are increasingly acknowledged at the global level as valuable marine foods, abundant in proteins, dietary fiber, essential vitamins, minerals, and bioactive metabolites. Regular consumption has been associated with multiple health-promoting effects, including antioxidant, anti-inflammatory, and metabolic benefits. In addition to their nutritional significance, seaweed cultivation contributes to environmental sustainability by enhancing carbon sequestration and requiring minimal external inputs. This review underscores the nutritional profile, therapeutic potential, processing methods, diverse applications, and future prospects of edible seaweeds, with particular attention to their role in food security and sustainable development.