Retinoids play a vital role as immunomodulators, influencing both innate and adaptive immune responses. They support the development and function of immune cells, including T-cells, macrophages, and dendritic cells, thereby helping regulate inflammation and maintain immune balance. RA, the active form of retinoids, is particularly important in fine-tuning these responses to protect against infections and reduce the risk of autoimmune reactions. Retinoids also contribute significantly to mucosal immunity and the maintenance of epithelial barriers, offering critical defense against respiratory and gastrointestinal infections. Their anti-inflammatory properties make retinoids promising in managing chronic inflammatory and autoimmune diseases such as inflammatory bowel disease, rheumatoid arthritis, and multiple sclerosis. These benefits are best achieved through a well-balanced diet rich in vitamin A sources—both preformed vitamin A from animal products and provitamin A carotenoids from plants—rather than through supplementation, which may carry risks of toxicity. In addition to their immune benefits, retinoids support skin health, vision, and cellular growth, while certain carotenoids also provide antioxidant protection against oxidative stress-related diseases, including some cancers and age-related macular degeneration. As research in nutritional immunology advances, the role of retinoids in disease prevention and immune regulation becomes increasingly evident. Emphasizing dietary intake of retinoid-rich foods can enhance immune function and contribute to overall health. In conclusion, retinoids represent key nutrients with therapeutic potential in immune-related conditions, highlighting the importance of nutrition in health maintenance and disease prevention.