Title: Onion In Traditional And Modern Medicine: Whole Plant Perspectives And Future Directions
Authors: Ahmed Attahiru, Abubakar Umar Birnin-Yauri and Bashar Attahiru
Volume: 9
Issue: 8
Pages: 60-68
Publication Date: 2025/08/28
Abstract:
: Onion (Allium cepa L., Amaryllidaceae) is one of the oldest cultivated vegetables and continues to hold both nutritional and medicinal relevance. Its widespread culinary acceptance across cultures often obscures the long history of its role in traditional medicine. Historical texts and ethnobotanical surveys describe its application in respiratory ailments, gastrointestinal disorders, cardiovascular health, and infections, reflecting its use in diverse traditional systems including Ayurveda, Traditional Chinese Medicine, Unani, and African ethnomedicine. Contemporary research increasingly supports these uses, identifying a broad range of phytochemicals responsible for bioactivity. Different plant parts contribute distinct therapeutic properties. The edible bulb, rich in flavonoids such as quercetin, sulfur containing compounds like thiosulfinates, and fructans, has been linked to antioxidant, antimicrobial, antidiabetic, and cardioprotective effects. Onion peel, once considered agricultural waste, has emerged as a superior source of quercetin glycosides and phenolic acids, while seeds contain fatty acids and sterols with metabolic and anti-inflammatory potential. Leaves and roots, although less explored, contribute flavonoids, carotenoids, and saponins that may extend onion's pharmacological spectrum. Recent advancements highlight onion's role as a functional food and nutraceutical candidate. Randomized controlled trials confirm beneficial effects on blood pressure, lipid profiles, obesity indices, and glycemic control, although issues of poor bioavailability and limited long-term safety data remain. Innovative extraction technologies, including ultrasound assisted, microwave, subcritical water, and natural deep eutectic solvents, are paving the way for sustainable valorization of onion by-products within circular economy models. This review integrates ethnobotanical, phytochemical, pharmacological, and clinical evidence to provide a whole plant perspective. It further outlines safety considerations and identifies future research opportunities. Onion represents an exemplary case where traditional knowledge aligns with modern science, underscoring its potential as both a staple food and a therapeutic resource in addressing global health challenges.