National Nutrition Month: Fighting Iron Deficiency

Iron is one of the best studied micronutrients. It is a key element in our metabolism and is an essential component of hundreds of proteins and enzymes. Iron is needed to make hemoglobin, a protein on red blood cells, that transports oxygen and carbon dioxide around the body. It picks up oxygen in the lungs, takes it to tissues to drop off, then it picks up carbon dioxide in those tissues and takes it back to the lungs where it is exhaled. Iron is also necessary for the production of energy as ATP in the cells. It is a part of enzymes that act as antioxidants to protect our cells from damage as well as pro-oxidant enzymes that destroy foreign pathogens in the body. DNA synthesis also depends on an iron-dependent enzyme. Iron affects nearly every function in our bodies.

What happens when we don't get enough iron? And how do we prevent that from happening?

Symptoms of Iron Deficiency

When the body does not absorb the amount of iron needed, it becomes iron deficient. Symptoms of iron deficiency do not appear until it has progressed to iron deficiency anemia. This is a condition where the body's stores of iron are so low that not enough red blood cells can be made to carry oxygen in the body efficiently. Iron deficiency is the leading cause of anemia in the U.S. The Centers for Disease Control and Prevention (CDC) estimates that 9.6% of residents in the U.S. have iron-deficiency anemia.

Symptoms include:

• Fatigue

• Pale skin and fingernales

• Dizziness

• Weakness

• Headache

• Glossitis (inflamed tongue)

• Shortness of breath when exercising

High-Risk Individuals

The following populations of people are at higher risk for developing iron deficiency.

• Pregnant or Breast-feeding women: they have an increased blood volume which requires more iron to provide oxygen to the baby and growing reproductive organs.

• Infants and children ages 6 months - 4 years old: a newborn usually has enough iron stores to last for 6 months. After 6 months, iron needs increase due to growht. Breast milk and iron-fortified infant formula can supply the iron not being met by solid foods. Cow's milk is a poor source of iron. Children that drink too much milk can have other foods crowded out and may develop "milk anemia." 2 cups of milk per day is the recommendation for toddlers.

• Adolescent girls: this is a time of rapid growth and for girls, the start of menstration which increased blood loss, causing iron loss. This combined with often inconsistent or restrictive diets places adolescent girls at risk.

• Individuals with Celiac disease: this autoimmune disorder causes damage to the intenstinal villi, the structures in the intestines where nutrients are absorbed, when the person eats gluten. The damage to intestinal cells may result in malabsorption of many nutrients including iron.

• Vegetarians: iron from plants is less effectively absorbed than that from animal sources. The recommended dietary allowance (RDA) is therefore increased for vegetarians.

Sources of Iron

The best absorbed form of iron comes from animal sources. The body absorbes 2-3 times more iron from meats than from plants. Some of the best dietary sources of iron are:

• Lean beef

• Turkey

• Chicken

• Fish

• Lean pork

Although less iron is absorbed from plants, they can still provide a good source of iron, especially for vegetarians. Adding vitamin C will enhance iron absorption. Plant sources include:

• Beans (pinto, kidney, soybeans, lentils)

• Dark green leafy vegetables (spinach especially)

• Fortified breakfast cereals

• Enriched rice

• Whole grain and enriched breads

Iron Supplements

Iron supplements may help prevent and treat iron deficiency. Those who are not at risk for iron deficiency (men and post-menopausal women) should not take iron supplements without the supervision of their doctor. Iron toxicity is serious. Iron supplements are best absorbed on an empty stomach, however they often cause upset stomach. You may take iron supplements with food but this decreases their absorption. Iron supplements may also cause nausea, constipation, and decreased appetite. They should be taken away from zinc supplements as they may decrease zinc's absorption, and also away from any antacids. Vitamin C taken with an iron supplement will help increase its absorption.

Recommended Dietary Allowance (RDA) for Iron

Adults between the ages of 19-50 should have 8 mg/day for males and 18 mg/day for females. Both male and female adults age 51 or older should have 8 mg/day. Pregnant women should have 27 mg/day of iron. Infants from 7-12 months old should have 11 mg/day.

How to Prevent Iron Deficiency

Eating a balanced, healthy diet that includes good iron sources is usually enough to prevent deficiencies. Combining vegetarian sources of iron with vitamin C at a meal can improve iron absorption. For example: bell pepper and bean salad, spinach with lemon juice, fortified cereal with orange juice to drink. If treatment is necessary, a medical professional will assess iron status and determine how to treat it, which may include increasing dietary sources of iron or a supplement.

Resources:

1) Higdon J. "Iron." Linus Pauling Institute. http://lpi.oregonstate.edu/mic/minerals/iron. Updated in August 2009. Accessed March 14, 2016.

2) Kaufman C. "Foods to Fight Iron Deficiency." Academy of Nutrition and Dietetics. http://www.eatright.org/resource/health/wellness/preventing-illness/iron-deficiency. Published January 6, 2016. Accessed March 14, 2016.

3) "Anemia or Iron Deficiency." Centers for Disease Control and Prevention. http://www.cdc.gov/nchs/fastats/anemia.htm. Updated April 8, 2015. Accessed January 9, 2013.