Urbanization and global population growth have reduced cultivable land, intensifying the demand for renewable and sustainable nutrient sources. Algae have emerged as a potent biological reservoir rich in bioactive compounds with diverse therapeutic potential. Among these, algal-derived vitamins represent a promising natural alternative to synthetic supplements due to their superior bioavailability, environmental sustainability, and physiological efficacy. These vitamins, encompassing both fat-soluble (A, D, E, and K) and water-soluble (B-complex and C) groups, play essential roles in vision, immunity, bone health, and energy metabolism. Unlike synthetic forms, algal vitamins are derived from renewable biomass, offering enhanced safety and reduced ecological impact. This chapter highlights the bioactivity, stability, and therapeutic efficacy of algal-derived vitamins, emphasizing their potential use in functional foods and nutraceutical formulations. Importantly, it also addresses toxicological considerations, such as excessive iodine intake and risks of hypervitaminosis, that may arise from overconsumption or improper formulation, underscoring the need for careful dosage regulation. Collectively, this overview presents algae as a sustainable foundation for next-generation dietary supplements, offering significant health benefits while encouraging balanced and safe utilization in the development of natural, eco-friendly nutritional alternatives.