Cancer
Studies have demonstrated that diets high in dark green vegetables such as spinach are associated with a decreased risk of colon cancer. Researchers have identified at least thirteen different flavonoid compounds in spinach that function as antioxidants and as anticancer agents

Eyesight
Spinach is one of the richest dietary sources of lutein, a carotenoid that has been implicated as being protective against cataracts and other age related macular degeneration. In a study at Harvard Medical School in Boston, higher dietary intakes of lutein and vitamin E from food and supplements were associated with significantly decreased risks of cataract.

Heart Disease
Spinach is an excellent source of folate, which may decrease homocysteine, an amino acid found in blood. A high level of homocysteine is a risk factor for cardiovascular disease

Alkaline
Spinach is an alkaline producing food, making it useful in helping to regulate body pH.