Scallions are very low in calories; 100 g of fresh leaves provide just 31 calories. Nonetheless, they contain many noteworthy flavonoid anti-oxidants, plant fiber, minerals, and vitamins that have proven health benefits.
Being a leafy-greens, scallions naturally carry more plant-derived antioxidants, and dietary fiber than their fellow bulb (allium) members like onions, shallots, etc. 100 g fresh spring onions provide 2.6 g or 7% of daily-recommended levels of fiber.
Scallions, like leeks, possess proportionately less thio-sulfinates anti-oxidants than that in the garlics. Thio-sufinates such as diallyl disulfide, diallyl trisulfide and allyl propyl disulfide convert into allicin through enzymatic reaction when its leaves subjected to crushing, cutting, etc. Laboratory studies show that allicin reduces cholesterol production by inhibiting the HMG-CoA reductase enzyme in the liver cells. Further, it also found to have anti-bacterial, anti-viral, and anti-fungal activities.
Allicin decreases blood vessel stiffness by release of nitric oxide (NO), and thereby, bring a reduction in the total blood pressure. In addition, It inhibits platelet clot formation and has fibrinolytic action in the blood vessels, which helps decrease an overall risk of coronary artery disease (CAD), peripheral vascular diseases (PVD), and stroke.