There are a few reasons this can happen.
Gastrointestinal issues can keep your body from getting iron from the foods you eat. “As you get older, the cells in your stomach lining can die off, so you don’t absorb iron properly,” says Michael Auerbach, a clinical professor of medicine at Georgetown University in D.C.
Certain medicines, such as those for acid reflux, may also interfere with iron metabolism. Taking low-dose aspirin every day raised the risk of anemia by 20 percent in older adults, according to a 2023 study published in the Annals of Internal Medicine. Aspirin can cause gastrointestinal bleeding and reduce iron levels through blood loss.
An underlying health issue also can cause iron deficiency, says Caroline Cromwell, an assistant professor of medicine at the Icahn School of Medicine at Mount Sinai in New York. Some conditions that are common in older adults — such as ulcers, colon polyps and cancer — can cause internal bleeding, she says.
If you suspect that you’re low in iron or have any signs of anemia, such as fatigue, dizziness, shortness of breath, and cold hands or feet, see your health-care provider before you take any action.
Men and women over 50 require 8 milligrams of iron a day. “Most American adults get enough iron through diet,” says Vijaya Surampudi, an assistant professor of medicine at UCLA’s Center for Human Nutrition in California.
But vegans and vegetarians may need to get up to 15 mg, she says. That’s because the body absorbs just 1 to 10 percent of the iron in plants and iron-fortified foods, called nonheme, compared with 25 to 30 percent of the heme iron found in meat, fish and poultry.
To aid iron absorption from plant foods, eat those with vitamin C (such as citrus, tomatoes, bell peppers and broccoli) at the same meal. Research suggests that this can help you get as much as seven times the iron from plant-based sources.
Consider what you’re drinking, too. Coffee and tea reduce iron absorption. Antioxidants in these drinks called polyphenols can bind to iron, blocking them from entering the bloodstream, Surampudi says. Stop sipping those beverages an hour or more before your meal.
Iron is found in both animal and plant foods. Here are some top sources of iron.
- Fortified breakfast cereal, 1 serving: 18 mg.
- Oysters, cooked, 3 ounces: 8 mg.
- White beans, canned, 1 cup: 8 mg.
- Lentils, cooked, 1 cup: 6 mg.
- Tofu, firm, 1 cup: 6 mg.
- Beef, top round, cooked, 4 ounces: 4 mg.
- Potato, baked, 1 medium with skin: 2 mg.
- Pumpkin seeds, 1 ounce: 2 mg.
- Stewed tomatoes, canned, ½ cup: 2 mg.
- Bread, white or whole wheat, 1 slice: 1 mg.
- Chicken, roasted, 4 ounces: 1 mg.
Should you take an iron supplement?
Given this information, you may be tempted to take iron pills as insurance. Don’t do so without talking to your doctor, Cromwell says. There are other types of anemia, and supplements can mask the symptoms of iron-deficiency anemia. This can delay a diagnosis of any medical issue that’s triggering the iron shortage.
What’s more, your body holds on to iron, so you can get too much. A 2001 study in the American Journal of Clinical Nutrition found that 13 percent of White Americans ages 67 to 96 had iron levels that were too high, in part because of taking supplements. An excess of the mineral can trigger digestive problems, such as cramps and nausea, Cromwell says.
And in the long run, iron can build up and harm the organs where it’s stored, such as the liver or heart. Research has also linked iron overload to a higher risk of Type 2 diabetes, certain heart conditions and cancer.
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