March's Health Genie: Iron
Dear Genie,
What can you tell me about iron? My husband and I have a new baby. I feel I could be anemic. We could both use something to support our energy. I never took multivitamins until my pregnancy so I am unsure about what to take now that I am no longer pregnant. My husband’s doctor urged him to avoid iron supplementation. I have heard that too much iron can be harmful to children. Should I be cautious about how much iron I take while I am nursing? Should we try to get our iron from food alone?
Thanks,
Tired Tina
Dear Tina,
Congratulations on the new addition to your family. You are wise to be cautious about your infant’s iron intake. While you may benefit from an iron supplement, too much iron can cause constipation or even be very harmful to a child. For your husband, with respect to iron, what’s good for the goose is not good for the gander. One of the main differences between multivitamins formulated for men and those for women is iron content. Because there are few ways, short of bleeding that our bodies shed unused iron, men and postmenopausal women are advised not to supplement iron. Younger women can supplement iron. For children the recommendation is based on diet or iron level.
Iron is a part of many proteins and enzymes in the body, most notably the oxygen carrying protein hemoglobin. Deficiency can result in fatigue, poor mental or physical work performance and decreased immunity. Generally women of childbearing age and young children are low in iron. Most women lose about 30 to 40 mg per monthly cycle. Vegetarians may also be low, depending on their diet. Most others have adequate levels if their intestinal absorption is not impaired. Iron is absorbed primarily in the small intestine. We absorb iron best when we are deficient. When our iron levels are high we absorb poorly.
Most infants are born with a supply of iron that lasts four to six months and infants absorb iron extremely well from breast milk. However it is still somewhat common to hear of an infant with low iron. Pediatricians often recommend an iron supplement for the mother or baby in this case. For one, low iron levels make children more susceptible to absorbing lead if it is in their environment. However, high amounts can cause constipation, and accumulation can be toxic. It is important to keep iron supplements out of reach of children. A single 300 mg dose can be fatal to small children.
How should you ensure the appropriate supply for you and your baby? The RDA for a lactating woman (9-10 mg) is actually lower than that for other women of reproductive age (15-18 mg). It is about a third that for pregnant women (27mg). This is not to say that you might not be low in iron following pregnancy and childbirth. Pregnancy can deplete iron stores. Any iron required for development of the baby goes to that purpose. Many women are low in iron after pregnancy. To give you an idea, in pregnancy women transfer 500-1000 mg of iron per day to the baby. While breastfeeding women lose about 1 to 2 mg per day. You can probably safely take a women’s or basic multivitamin with iron. It’s best to have your level and your child’s checked before choosing a multivitamin especially high in iron or a single iron supplement. Prenatal vitamins can be used during breastfeeding but the amount of iron is usually much higher based on a higher recommended daily allowance.
The RDA for men is between 8-11 mg. Most consume an adequate supply. As for why your husband’s doctor strongly suggested he avoid iron, there is much research pointing to a correlation between iron and heart disease. This is the main reason why only the populations at risk of low iron or individuals found to have low iron are advised to supplement. Still the collection of research on iron and heart disease is mixed and inconclusive about whether the iron directly contributes to heart disease, or if it is coincidental to other factors. Interestingly men may be able to reduce their risk of heart disease by donating blood regularly over a long period of time. This temporarily reduces blood iron and most people are able to replace the supply by eating a balanced diet.
That brings us to your final question, about food. There are two forms of iron in food. Heme iron is by far the best absorbed and it occurs only in meat. Non heme iron is high in many plant protein sources, soy, lentils, quinoa, pumpkin seed, chickpea, tempeh, spinach, sesame, almonds, peas, sunflower seed, cashew and also in dark greens, raisins, figs, apricots, bulgur, broccoli and watermelon. Using iron cookware can also increase your iron intake, and it is understood to be safe. Milled grains have less iron than whole grains. Meat protein and vitamin C improve absorption of heme iron. Tannins in tea and coffee, calcium, polyphenols and phytates present in many vegetarian sources of protein and iron, can decrease absorption of non heme iron. This is why vegetarians may need to consume a greater amount of iron than those who eat meat and fish regularly.
There are many multivitamins and iron supplements to choose from in City Market’s wellness department, standard, food based, and two varieties of liquid iron made from herbs and food. The friendly staff can direct you to the selection and make suggestions about how to prepare and enjoy foods rich in iron.
Good Luck!
The Health Genie
Sources:
- Hass, Elson, M, MD. 2006. Staying Health with Nutrition. Celestial Arts, Toronto.
- National Institute of Health, Office of Dietary Supplements. 2011. Iron Fact Sheet.