The Irony of Iron
Iron is one of the most abundant minerals in nature and most life forms require it, including humans. Ironically, it is also the most common nutrient deficiency in the world and in America, according to the Center for Disease Control, National Institute of Health and World Health Organization.
What is Iron?
Iron is found in all human cells. It is also a part of many enzymes and proteins that are vital to the normal functioning of our bodies. Iron, as a part of the protein hemoglobin (the pigment in red blood cells) is responsible for carrying oxygen throughout our bodies. Most of our body’s iron is found in hemoglobin. Smaller amounts are found in myoglobin, a protein that helps distribute oxygen to muscles. Iron also helps our muscles store and use oxygen. And traces of it can be found in liver, spleen, bone marrow and in our muscles. Other than oxygen transport and storage, iron is a part of other metabolic processes including DNA synthesis and electron transport. As a part of many enzymes, iron helps with proper digestion. It is also known to help cell growth and differentiation.
According to Marcel E Conrad, MD, in healthy people iron equilibrium (approximately 60 parts per million) in the body is regulated carefully by the small intestine to ensure that sufficient iron is absorbed in order to compensate for body losses of iron. Iron in excess of these requirements is deposited in body stores as ferritin or hemosiderin.
What is Iron Deficiency?
Iron deficiency is a condition resulting from not having enough iron in the body. Iron deficiency is the most common nutritional deficiency and the leading cause of anemia in the United States. The terms anemia, iron deficiency, and iron deficiency anemia often are used interchangeably but not the same. Iron deficiency ranges from depleted iron stores without functional or health impairment to iron deficiency with anemia, which affects the functioning of several organ systems.
What are the symptoms?
Fatigue, lethargy, shortness of breath, dizziness, weakened immune system, drowsiness, focus and memory problems, decreased performance at work/school, slow cognitive and social development during childhood, difficulty maintaining body temperature and an inflamed tongue. As you may have noticed, since iron plays an important role in oxygen transport, many of the symptoms are a related to oxygen deprivation.
What are the causes of iron deficiency?
There are three common reasons for not having enough iron in the body: blood loss, not getting enough iron in your diet or poor absorption of iron.
- When your body loses blood, it is losing iron. One of the most common forms of blood loss is through heavy menstrual periods. This is one of the reasons iron deficiency is common in women along side pregnancy. A woman loses about 500 mg of iron with each pregnancy. Menstrual losses are highly variable, ranging from 10-250 mL (4-100 mg of iron) per period. These iron losses in women double their need to absorb iron in comparison to males. Other forms of blood loss can be through donations, operations or gastrointestinal conditions or disease.
- The people who have low iron levels due to low intake must increase consumption of iron rich foods. There are two forms of dietary iron: heme and nonheme. Both forms are absorbed non-competitively. Many of the factors that alter the absorption of nonheme iron have little effect upon the absorption of heme iron because of the differences in their chemical structures. Heme iron is derived from hemoglobin, the protein in red blood cells that delivers oxygen to cells. Heme iron is found in animal foods that originally contained hemoglobin, such as red meats, fish, and poultry. Iron in plant foods such as lentils and beans is arranged in a chemical structure called nonheme iron. This is the form of iron added to iron-enriched and iron-fortified foods. Heme iron is absorbed better than nonheme iron, but most dietary iron is nonheme iron. Foods that contain heme iron are lean cuts of beef, chicken, turkey, clams, oysters, shrimp, halibut, tuna, organ meats and eggs. Foods that contain non-heme iron include spinach, beans, peas, nuts, Brussels sprouts, potatoes, wheat bread, soybeans, lentils, blackstrap molasses and chickpeas. Some food manufacturers have added iron to their food products to increase the nutritional value. Foods that have been enriched are certain brands of oatmeal, breakfast cereals, veggie dogs and burgers, yogurt, white bread and snack bars.
- An adult male absorbs and loses about 1 mg of iron from a diet containing 10-20 mg daily. During childbearing years, an adult female loses an average of 2 mg of iron daily and must absorb a similar quantity of iron in order to maintain equilibrium. Because the average woman eats less than the average man does, she must be more than twice as efficient in absorbing dietary iron in order to maintain equilibrium and avoid developing iron deficiency anemia. Storage levels of iron have the greatest influence on iron absorption. Iron absorption increases when body stores are low. When iron stores are high, absorption decreases to help protect against toxic effects of iron overload. Iron absorption is also influenced by the type of dietary iron consumed. Absorption of heme iron from meat proteins is efficient. Absorption of heme iron ranges from 15% to 35%, and is not significantly affected by diet. In contrast, 2% to 20% of nonheme iron in plant foods such as rice, maize, black beans, soybeans and wheat is absorbed. Meat proteins and vitamin C will improve the absorption of nonheme iron. Some products that decrease iron absorption: red wine, coffee, tea, whole grains, and soy products.
Iron deficiency has wide social and economical implications because it diminishes the capability of individuals who are affected to perform physical labor, and it diminishes both growth and learning in children.
People that are at highest risk of deficiency:
- Young children and pregnant women are at higher risk of iron deficiency because of rapid growth and higher iron needs.
Adolescent girls and women of childbearing age are at risk due to menstruation.
- Among children, iron deficiency is seen most often between six months and three years of age due to rapid growth and inadequate intake of dietary iron. Infants and children at highest risk are the following groups:
- Babies who were born early or small.
- Babies given cow’s milk before age 12 months.
- Breastfed babies who after age 6 months are not being given plain, iron-fortified cereals or another good source of iron from other foods.
- Formula-fed babies who do not get iron-fortified formulas.
- Children aged 1–5 years who get more than 24 ounces of cow, goat, or soymilk per day. Excess milk intake can decrease your child’s desire for food items with greater iron content, such as meat or iron fortified cereal.
- Children who have special health needs, for example, children with chronic infections or restricted diet.