Foods That Inhibit Iron Absorption
The foods that make up your diet can influence how well your body absorbs iron — so watch out for these common inhibitors of iron absorption.
Iron, an essential vitamin, is responsible for transporting oxygen throughout the body, according to the National Institutes of Health. There are two types of dietary iron: heme iron and non-heme iron. Heme iron is found only in meat, fish and poultry, while non-heme iron is found mostly in fruits, vegetables, dried beans, nuts and grain products. Iron deficiency anemia occurs when red blood cells do not contain an adequate amount of iron due to pregnancy, blood loss, a diet low in iron, or poor absorption of iron by the body. Knowing what foods inhibit iron can help keep the body functioning efficiently.
Eggs and Iron
Eggs are a common inhibitor of iron absorption. Eggs contain phosvitin, a protein compound that binds iron molecules together and prevents the body from absorbing iron from foods. According to the Iron Disorders Institute, one boiled egg can reduce iron absorption by as much as 28 percent.
Calcium-Rich Foods
Milk can also work as an inhibitor of iron absorption, potentially affecting your iron levels. Milk contains calcium, an essential mineral and the only known substance to inhibit absorption of both non-heme and heme iron. One cup of milk contains approximately 300 mg of calcium. Calcium has little or no effect on iron absorption when less than 50 mg is ingested, but it can inhibit heme iron and non-heme iron absorption when 300 to 600 mg is consumed on a daily basis. Large amounts of calcium can also be found in yogurt, cheese, sardines, canned salmon, tofu, broccoli, almonds, figs, turnip greens and rhubarb.
Foods High in Oxalates
If you consume large amounts of tea with your meals, you may not be receiving an adequate amount of iron from those foods, according to the website VeganHealth.org. Tea contains oxalates — oxalic acid compounds that impair the absorption of non-heme iron. Oxalates can also be found in spinach, kale, beets, nuts, chocolate, wheat bran, rhubarb, strawberries and herbs such as oregano, basil and parsley.
Polyphenol-Rich Foods
Cocoa and coffee are food sources that can inhibit iron absorption in the body. These foods sources contain polyphenols or phenolic compounds, antioxidants that help remove damaging free-floating cells from the body — which means that morning cup of coffee inhibits iron. According to the Iron Disorders Institute, cocoa can inhibit 90 percent of iron absorption in the body, while one cup of coffee can prevent iron absorption by as much as 60 percent. Phenolic acid can also be found in apples, peppermint and some herbal teas, spices, walnuts, blackberries, raspberries and blueberries. It is important to note that these foods should not be consumed two hours prior to, or following, your main iron-rich meal.
Foods High in Phytates
Walnuts can reduce the amount of iron your body absorbs from iron-rich foods. Walnuts contain phytates — compounds found in soy protein and fiber. Even low levels of phytates have a strong inhibitory effect on your body's ability to absorb iron from foods. According to the Iron Disorders Institute, phytates can reduce iron absorption from food by approximately 50 to 65 percent. Phytates can also be found in almonds, sesame, dried beans, lentils, peas, cereals and whole grains.