Low Iron Levels in Humans

Iron is an essential mineral that is found in every cell of your body. The body requires it to make hemoglobin, found in red blood cells, and myoglobin, found in muscles, which are both oxygen-carrying proteins. Iron is also required for your body to regulate cell growth and cell differentiation. Some of the best food sources for iron include liver, lean red meat, poultry, salmon, tuna, oysters, eggs, dried beans, dried fruits, whole grains and iron-fortified cereals.

RDA for Children

The Recommended Dietary Allowances, RDA, for infants ages 0 to 6 months is 0.27 mg a day; it increases to 11 mg a day for ages 6 to 12 months. For children ages 1 to 3 the RDA is 7 mg a day; for ages 4 to 8 it is 10 mg a day; for ages 9 to 13 the RDA goes down to 8 mg a day. In male adolescents, ages 14 to 18, the RDA is 11 mg a day. In female adolescents, ages 14 to 18, the RDA is 15 mg a day, except in the case of pregnancy and lactation, when the RDA become 27 mg and 10 mg a day, respectively.

RDA for Adults

The RDA for men ages 19 and over remains constant at 8 mg a day. The RDA for women, ages 19 to 50, is 18 mg a day. In women over the age of 51, the RDA decreases to 8 mg a day. These recommendations change during pregnancy and lactation, to an RDA of 27 mg a day during pregnancy and 9 mg a day while lactating.

Symptoms of Deficiency

An iron deficiency usually starts with a negative iron balance, in which you are not getting enough iron to meet your needs and your body will use your stored iron sources. You may experience fatigue, headaches and irritability, though symptoms may be so mild they are unnoticed. An advanced depletion of iron causes iron deficiency anemia. Symptoms of iron deficiency anemia are extreme fatigue, weakness, shortness of breath, pale skin, dizziness, soreness of your tongue, cravings for nonnutritive substances like dirt, brittle nails, fast heartbeat, restless leg syndrome and a poor appetite, especially in infants and children.

Risk Factors

Iron deficiency is associated with excessive blood loss, inadequate iron absorption and a low dietary intake of iron. People who are at risk of iron deficiency include frequent blood donors, women, due to their high iron needs and the fact they lose iron during menstruation, infants and children, especially infants born at a low birth weight and children who do not eat a balanced diet, and vegetarians. Conditions that put you are higher risk of iron deficiency include those that cause gastrointestinal bleeding, such as colon cancer or a peptic ulcer, and those that cause poor absorption, like Crohn's disease, celiac disease and having had gastric bypass surgery.