Heme iron is found in high amounts in animal products such as meat, fish and poultry, while nonheme iron comes in the form of plant-based foods such as nuts, seeds, legumes and dried fruit. Absorption of heme iron is consistent and less variable than the digestion of nonheme iron. Substances present in food and the body either enhance or inhibit absorption of nonheme iron. Although the mechanism is not well-known, MFP factor helps with absorption of nonheme iron.
Optimizing Your Iron
MFP factor refers to the digestion products of meat, fish and poultry. Proteins in meat, fish and poultry are digested into peptides -- short chains of amino acids -- that contain the amino acids cysteine and histidine, which are thought to enhance the body's ability to absorb nonheme iron. To maximize absorption of nonheme iron, consume 75 units of MFP factor -- 1 unit is equivalent to 1.3 grams of cooked meat, fish or poultry -- along with your nonheme iron source. For example, eat 3.5 ounces of chicken breast with 1 cup of cooked broccoli and 1/2 cup brown rice. Another idea is a spinach salad with 3.5 ounces of sirloin topped with almonds, apricots and a citrus vinaigrette.