Health benefits of onion

Onion (Allium cepa L.) is one of the most widely used vegetable crops, belonging tothe Liliaceae family. It is found across a wide range of latitudes and altitudes in Europe,Asia, North America, and Africa. Onions are rich in health promoting dietary flavonoidsand the alk(en)yl cysteine sulfoxides (ACSOs). The anthocyanins in onion impart ared/purple color to some varieties and flavonols, such as quercetin and its derivatives, areresponsible for the yellow and brown skins of many other varieties. Promising resultshave been obtained from both in vitro and in vivo investigations. Thus far, potentialhealth benefits include antibacterial, antithrombotic, antiplatelet, and anti-asthmaticactivities. Onions also exhibit immune modulatory, cardio-protective, nephro-protective,and anti-diabetic effects. This chapter reviews the spectrum of health protective effectsand the related mechanisms of action of onion phytonutrients.