Rice Beyond Cereal: A Review on the Evolution of Rice from Staple to Superfood

Rice (Oryza sativa L.) is one of the world's most important staple crops, providing a major source of dietary energy and playing a significant role in the cultural and agricultural heritage of many countries, particularly India. However, rice's potential extends beyond its conventional role as a cereal grain, as its bran and associated bioactive compounds offer considerable nutritional and functional value. This review highlights rice's emerging potential as a functional food, with particular emphasis on rice bran oil (RBO), γ-oryzanol, vitamin E, and tocotrienols. A favourable fatty acid composition characterises rice bran oil, which contains several bioactive constituents, including phytosterols, γ-oryzanol, tocopherols, and tocotrienols. These compounds have demonstrated antioxidant, lipid-regulating, anti-inflammatory, cardioprotective, antidiabetic, neuroprotective, and immunomodulatory properties in various experimental models. γ-Oryzanol has attracted considerable attention for its antioxidant activity, potential role in cholesterol regulation, and possible benefits in metabolic health. Tocotrienols have also shown promising biological activities related to cellular protection, inflammatory regulation, cardiovascular health, and bone preservation. Rice biodiversity, particularly indigenous rice varieties, also offers opportunities to identify valuable nutritional and bioactive traits. Nevertheless, these benefits vary by genotype, chemical composition, and experimental conditions, and many reported effects still require validation through well-designed human clinical studies. In addition, the evaluation of rice for functional and nutritional applications must address environmental contaminants and food safety considerations. Integrating rice biodiversity with advanced biochemical characterisation and targeted crop improvement could facilitate the development of rice-based functional foods and value-added products. Thus, exploring rice beyond its conventional role as a staple cereal offers promising opportunities for nutritional innovation, agricultural diversification, and the sustainable utilisation of rice-processing by-products.