I used to test low in iron. I take BarleyLife, a powdered whole food supplement that is loaded with chlorophyll, as well as enzymes, vitamins, minerals, anti-oxidants, etc. I no longer have issues with low iron. I think the chlorophyll might help the body absorb the iron in the diet more efficiently. Chlorophyll helps the body to heal itself. I call myself Green Lady because green is the color of LIFE.
Iron pills are harsh on the system and do constipate. Some recommend taking them with foods containing Vitamin C to aid in iron's absorption.