Kale is a leafy green cruciferous vegetable

Kale is a leafy green cruciferous vegetable that is chock full of essential vitamins A, C and K as well as minerals like copper, potassium, iron, manganese and phosphorus. A cup of fresh kale has only about 40 calories but packs almost 3 grams of protein. One cup of cooked kale has over 1000% more vitamin C than a cup of cooked spinach and unlike spinach, kales oxalate content is very low which means that the calcium and iron in kale are highly absorbable in the human digestive system.