If your iron is getting too low and you fear you may develop anemia, monitor your diet to ensure that you're receiving adequate amounts of iron. Not only does this entail attempting to eat foods that are high in iron or that increase iron absorption, it also includes becoming avoiding foods that may potentially block or inhibit iron absorption.
To ensure that you're absorbing an adequate amount of iron, it is also necessary to know the difference between the two types of iron: heme and nonheme. Heme iron is derived from animal foods that once contained hemoglobin--such as poultry, fish and red meat. Nonheme iron comes from plants and is the form of iron added to iron-enriched or fortified foods. Most dietary iron is nonheme iron, yet heme iron is absorbed better by the body.
Calcium, Eggs and Antacids
According to the Iron Disorders Institute, calcium, an essential nutrient, is the only substance known to inhibit both heme and nonheme iron. It can be found in dairy products, tofu, canned salmon, broccoli, rhubarb, figs, almonds and turnip greens. Calcium amounts from 300 to 600 mg inhibit iron absorption, but 50 mg or less has little to no effect.
Eggs also contain an essential compound that inhibits iron: phosvitin. Phosvitin is a protein that binds to iron and inhibits its absorption. One boiled egg can reduce iron absorption in a meal by up to 28 percent, as noted by the Iron Disorders Institute.
MedlinePlus and the Iron Disorders Institute note that antacids, through reducing the amount of acid produced in your stomach, can inhibit iron absorption. However, this is very rare and mainly a danger if you have drastically low levels of stomach acid or no stomach acid at all.
Phytate is found in sesame seeds, walnuts, dried beans, peas, almonds, lentils cereals and whole grains. It is contained in soy protein and fiber; even very low amounts have a strong inhibitory effect on absorption. Phytate can reduce healthy absorption by up to 65 percent, as noted by the Iron Disorders Institute.
Nonheme iron is affected by oxalates. Oxalates are found in beets, spinach, nuts, kale, wheat bran, chocolate, oregano, tea, strawberries, rhubarb, basil and parsley. Even though spinach is high in iron, the iron in spinach is difficult to absorb due to the oxalates that bond to the iron.
Polyphenols or phenolic compounds are found in cocoa, peppermint, apples, coffee, raspberries, some herbs, black tea, blueberries, coffee, walnuts, blackberries and some spices. They have the ability to inhibit iron absorption. For instance, one cup of coffee can inhibit iron absorption up to 60 percent, and some Swedish cocoas and certain types of tea can inhibit absorption up to 90 percent, according to the Iron Disorders Institute. If you are eating an iron-rich meal, do not consume any of these foods within two hours before and two hours after the meal.