Nutrition Science and Everyday Application - beta v 0.1

VITAMINS AND MINERALS INVOLVED IN BLOOD HEALTH 537
• Dizziness
• Swollen, sore tongue
• Abnormal heart rate
Infants, children, adolescents, and women are the populations most at risk worldwide for
iron-deficiency anemia. 4 Infants who are premature, low birthweight, or have a mother
with iron deficiency are at risk for iron deficiency, because they are born with low iron
stores relative to the amount needed for growth and development. Young children and
adolescent girls are at risk for iron deficiency due to rapid growth, low dietary intake of
iron, as well as heavy menstruation for adolescent girls. In these populations, iron-deficiency
anemia can also cause the following signs and symptoms: pica (an intense craving for and
ingestion of non-food items such as paper, dirt, or clay), poor growth, failure to thrive, and
poor performance in school, as well as mental, motor, and behavioral disorders. Women
who experience heavy menstrual bleeding, or who are pregnant, are also at risk for iron
inadequacy due to their increased requirements for iron.
To give you a better understanding of these risks, it is helpful to look at how much higher
the RDA is for women of reproductive age and pregnant women compared to men (Table
9.2). 1 To put this in perspective, 3 ounces of beef contains about 3 milligrams of iron, making
it challenging for some women to meet their daily iron requirement.
Population Group
Women of reproductive age, 19-50 years
Pregnancy, 19- 50 years
Men, 19-50 years
RDA for Iron
18 mg/day
27 mg/day
8 mg/day
Table 9.2. A comparison of the RDAs for adult women of reproductive age, pregnancy, and adult
men.
Additionally, those who frequently donate blood, as well as people with cancer, heart
failure, or gastrointestinal diseases such as Crohn’s, are at greater risk for iron inadequacy. 1
Iron deficiency progresses through three stages: 1
1. Mild depletion of iron stores – No physical symptoms will be present, because
hemoglobin levels are not affected, but there will be a decrease in ferritin (a
storage form of iron).
2. Iron-deficient erythropoiesis (erythrocyte or red blood cell production) – Iron
stores are depleted and iron transport is decreased due to a decrease in transferrin
(the transport protein for iron), but hemoglobin levels are usually within the
normal range.
3. Iron-deficiency anemia – Iron stores are exhausted and hemoglobin levels are
reduced, resulting in microcytic anemia (small red blood cells) and hypochromic
anemia (low color red blood cells).
Healthy adults are at little risk of iron overload from foods, but too much iron from
supplements can result in gastric upset, constipation, nausea, vomiting, and abdominal