Onions

"Onions are a nutrient-dense food, meaning that while they are low in calories they are high in beneficial nutrients like vitamins, minerals and antioxidants. Like garlic, it is a member of the lily family.

--The reason that the onion is so much more active in its raw state than when cooked, is that it contains a variety of organic sulphur compounds, contained in a volatile oil, that provide the health benefits. These are partly destroyed by heat.

Cancer: Allium vegetables have been studied extensively in relation to cancer, especially stomach and colorectal cancers. Their beneficial and preventative effects are likely due in part to their rich organosulfur compounds. Although the exact mechanism by which these compounds inhibit cancer is unknown, possible hypothesis include the inhibition of tumor growth and mutagenesis and prevention of free radical formation.

Sleep and mood: Folate, found in onions, may help with depression by preventing an excess of homocysteine from forming in the body, which can prevent blood and other nutrients from reaching the brain. Excess homocysteine interferes with the production of the feel-good hormones serotonin, dopamine, and norepinephrine, which regulate not only mood, but also sleep and appetite as well.

Skin and hair: Adequate intake of vitamin C is needed for the building and maintenance of collagen, which provides structure to skin and hair."
MedicalNewsToday