Spinach is one of the best-known vegetables that contains iron. Cooked spinach may provide more concentrated iron per serving than raw spinach. However, the iron in spinach is non-heme iron, which is absorbed less efficiently than animal-based heme iron. For better absorption, spinach can be paired with vitamin C-rich foods such as lemon, oranges, red peppers, or strawberries. Drinking large amounts of tea or coffee with meals may reduce iron absorption.