"Onions are super-healthy," said Victoria Jarzabkowski, a nutritionist with the Fitness Institute of Texas at the University of Texas at Austin. "They are excellent sources of vitamin C, sulphuric compounds, flavonoids and phytochemicals."
Phytochemicals, or phytonutrients, are naturally occurring compounds in fruits and vegetables that are able to react with the human body to trigger healthy reactions while Flavonoids are responsible for pigments in many fruits and vegetables.
Red onions are mainly made of carbohydrates and water as such they contain zero fat. They also provide significant amounts of vitamin C and vitamin B6 and they are also one of the best food sources of chromium.
Check out the following reasons you should incorporate red onions to their diet.