Ask The RD

Lourdes Castro, MS, RD, is an adjunct professor at New York University’s department of nutrition, food studies and public health; she earned her master’s degree in nutrition from Columbia University. She is the author of three cookbooks: Simply Mixican; Eat, Drink, Think in Spanish; and Latin Grilling. She is also the director of the Biltmore Culinary Academy in Miami. Visit her website at www.slicethin.com. Send your questions for Lourdes to swebster@ideafit.com.

Question: While I’m not a vegetarian, I’ve significantly reduced the amount of meat
I eat; I am concerned I’m not taking in enough iron. I do not want to resort to supplements, as I’ve heard they can cause constipation. How can I make sure I’m getting enough iron through my diet?

Answer: While we do not need large quantities of iron (women require 18 milligrams per day, and men require 8 mg per day), the small amount we must consume is very important, as it’s used to transport oxygen to cells and regulate cell growth. If we do not take in enough iron, our immune system slows and we begin to feel sluggish and fatigued as a result of limited oxygen delivery to cells.

Most people who eat a varied diet do not have to worry about consuming enough iron. However, anytime you adopt a dietary restriction—significantly decreasing the amount of meat you consume, for example—you need to be careful that your diet remains balanced.

What Foods Provide Iron?

There are two forms of dietary iron: heme and nonheme. While most dietary iron is nonheme, heme iron is the form our body absorbs best. That is because heme iron is derived from hemoglobin, the protein in red blood cells that delivers oxygen to cells. Heme iron is found abundantly in animal-based foods such as red meat, chicken and fish.

Nonheme iron is the form found in plant-based foods and is abundant in lentils, beans and fortified cereals. Our bodies do not do a very good job absorbing nonheme iron, but luckily there is something you can do to boost it. By consuming vitamin C with your plant-based or nonheme iron food source, you will improve its absorption. This is as easy as squeezing some lemon juice over your lentils or having an orange with your breakfast cereal. Just think of vitamin C sources that you can combine with your plant-based foods and you will keep your iron stores in check.