Many foods contain iron. The best is liver. Others high in iron are organ meats (kidneys, heart etc) chicken, eggs, fish, green leafy vegetables, whole grain breads & cereals, and nuts. Iron is important in your diet because it's major role is involved with the production of red blood cells. Lack of iron causes anemia resulting in fatigue, paleness, shortage of breath and possibly heart palpitations. Iron deficiency will also lead to you having lowered resistance to infection, becoming apathetic and irritable.