Iron rich foods: A guide for the science-minded parent

© 2009 Gwen Dewar, Ph.D., all rights reserved

The smart use of iron rich foods

If your child is iron deficient, it makes sense to examine his diet. But boosting iron levels isn’t just a matter of eating iron rich foods.

Some foods contain iron, but they also contain compounds that decrease the body’s ability to absorb iron.

For instance, many grains, legumes, and vegetables contain phytates--chemical compounds which bind to iron and then pass through the small intestine unabsorbed.

Eggs and spinach are sometimes touted as good sources of iron. But experiments and laboratory analyses suggest that the iron in these foods is poorly absorbed (Gordon and Chow 1984; Insel et al 2004; Ishikawa et al 2007).

Other foods, like milk, contain calcium, which competes with iron for absorption by the body (Insel et al 2004). As a result, kids who consume lots of milk may be at higher risk of iron deficiency, particularly if their iron rich meals are always accompanied by 40 mg or more of calcium (Gunnarson et al 2007; Hallberg 1998).

There are also foods that enhance iron absorption. Vitamin C and “meat factor” (found in red meat, salmon, and other animal muscle proteins) help the body absorb iron and counteract the effects phytates.

In one study, adding 63 mg of vitamin C to a grain-based, iron rich meal boosted iron absorption by almost 300% (Fidler et al 2009).

Here I list some foods that the USDA nutrient database reports as being high in iron. As you’ll note, these include

• Animal muscle tissue foods—shellfish, red meat, poultry, pork, and fish

• Iron-fortified grains (including breakfast cereals)

• Tomatoes

• Legumes

• Green leafy vegetables

• Dried fruits

Elsewhere, I offer tips for designing meals that promote iron absorption. These tips include:

• consuming iron rich foods in combination with sources of vitamin C (like citrus fruits, peaches, papayas, sweet red peppers, berries, broccoli, and peas)

• adding meat to meals rich in iron

• avoiding the consumption of high levels of calcium (>40 mg) during meals that are intended to boost iron levels

You should also try to avoid other iron absorption inhibitors, like tea, coffee, peppermint and chamomile. For more information about enhancing iron absorption, click here.

Iron rich foods: Sources of heme iron

Heme iron is the form of iron most easily absorbed by the body. It is found in animal muscle tissue. Here are some specific examples of heme iron rich foods, as rated by the USDA Nutrient Database.

Iron rich foods: Sources of nonheme iron

Nonheme iron is found in plant foods, as well as in meat and eggs. Compared with heme iron, nonheme iron is less efficiently absorbed. Moreover, many sources of nonheme iron also contain phytates, which greatly reduce bioavailability. If you want to absorb significant quantities of nonheme iron, it’s especially important to combine it with vitamin C or meat. Again, see my article on iron absorption for more information.

Here is a list of nonheme iron rich foods, compiled from the USDA Nutrient Database:

These tables represent only a small sampling of foods. For a more extensive listing of iron rich foods, check out the USDA Nutrient Database for yourself.

References: Iron rich foods

Fidler MC, Davidsson L, Zeder C, and Hurrell RF. 2004. Erythorbic acid is a potent enhancer of nonheme-iron absorption. Am J Clin Nutr. 2004 Jan;79(1):99-102.

Gordon DT and Chao LS. 1984 Relationship of components in wheat bran and spinach to iron bioavailability in the anemic rat. Journal of Nutrition 114(3): 526-535.

Gunnarsson BS, Thorsdottir I,and Palsson G. 2007. Associations of iron status with dietary and other factors in 6-year-old children. Eur J Clin Nutr. 61(3):398-403.

Hallberg L. 1998. Does calcium interfere with iron absorption? Am. J. Clin. Nutr. 68: 3-4.

Insel, PM, Turner RE, and Ross D. 2003. Nutrition. 2nd edition.

Ishikawa SI, Tamaki S, Arihara K, Itoh M. 2007. Egg yolk protein and egg yolk phosvitin inhibit calcium, magnesium, and iron absorptions in rats. J Food Sci. 72(6):S412-9.

Rutzke CJ, Glahn RP, Rutzke MA, Welch RM, Langhans RW, Albright LD, Combs GF Jr, and Wheeler RM. 2004. Bioavailability of iron from spinach using an in vitro/human Caco-2 cell bioassay model. Habitation (Elmsford). 10(1):7-14

Content last modified 6/9