Iron: The Blood Builder

According to Thomsen Ferreira, iron is one of the most common nutrient deficiencies in adult females. Iron deficiency, or anemia, affects as many as 5 million how to choose supplements Americans, according to the Harvard T.H. Chan School of Public Health.

Why is iron important?

Iron is a mineral that enables the blood to carry oxygen throughout the body. Everyone’s body uses iron to make two blood proteins. One, called hemoglobin, carries oxygen from the lungs to the rest of the body. The other, called myoglobin, carries oxygen to muscles, per the Office of Dietary Supplements. Iron is also essential for cell growth and hormones, notes the Harvard T.H. Chan School of Public Health.

Who needs it? How much iron a person needs depends on a host of factors, including age, sex, and whether you eat a plant-based diet, according to the Office of Dietary Supplements.

For women, heavy menstruation, being active, and pregnancy are factors that can cause low iron. “They also need more iron as the pregnancy progresses,” Thomsen Ferreira says.

How much should you take? The Office of Dietary Supplements recommends that females ages 14 to 18 who eat meat get 15 mg of iron a day. Females ages 19 to 50 should aim for 18 mg, and the amount drops after that. Females over age 50 need about 8 mg of iron daily, since they have typically started menopause and are no longer losing iron through menstruation. If you’re pregnant, the Office of Dietary Supplements recommends 27 mg, since the fetus requires lots of extra blood, and if you’re breastfeeding, you’ll need 9 mg. However, it’s more difficult to absorb iron from plant sources, so the Office of Dietary Supplements recommends getting nearly twice this much if you do not eat meat. But it is possible to get too much; adults shouldn’t typically get more than 45 mg of iron daily or it can cause health problems. Iron can also interact negatively with some Parkinson’s medications.

Calcium supplements can interfere with iron absorption, so if you’re taking both, or medications such as levodopa for Parkinson’s disease, levothyroxine for hypothyroidism, or proton pump inhibitors, you should take them at different times of day, warns the Office of Dietary Supplements.

If you’re worried about your iron levels, visit your doctor to have them checked. Good sources of animal-based iron are lean meat, seafood, and poultry, but iron also naturally occurs in white beans, lentils, spinach, kidney beans, and peas, as well as nuts and some dried fruits, such as raisins.

Pros
Easier to tolerate than some other forms
Robust testing program for quality and safety
Berry flavor and sugar-free
Cons
May be too much iron for some
May have a metallic taste
Iron supplements are notorious for upsetting the gastrointestinal tract, often leading to constipation or diarrhea. The good news is that there are different forms, and some may be easier on the stomach than others. Ferrous sulfate, ferrous gluconate, and ferrous fumarate are commonly found in supplements, but they can be harder to tolerate. Higher doses of these types of iron may cause stomach upset. If your body has trouble handling iron supplements, try ferrous bisglycinate instead.

“I recommend Nature’s Way Liquid Iron because it’s a gentle form of iron — iron bisglycinate — and it’s in a liquid form, which some women may tolerate better especially when pregnant and if they have an aversion to taking pills,” says Carroll. “This form is also gentle on your digestive system and may not lead to constipation, as other forms of iron can.”

We know certain medications can affect how much iron we absorb, but it’s important to know that certain foods can too. A review article published in September 2020 in the Journal of Nutrition and Metabolism concludes that soybeans, eggs, and calcium-containing foods can reduce how much iron our bodies absorb. Coffee and tea can have a significant impact as well. The same article found that coffee can reduce iron absorption by 39 percent and tea by 64 percent. Additional research should be conducted to support these findings.