The RDA for iron in men is 8 mg—for women, it’s 18 mg. The body uses iron in two key areas: to transport oxygen to tissue and cells, and to make hemoglobin for red blood cells. Insufficient iron causes anemia, a condition where the body produces fewer than normal red blood cells. Symptoms of anemia include fatigue, frequent infections and loss of appetite. The best food sources of iron include meat, fish, leafy greens and baked beans in tomato sauce. Some cereals are also good sources of iron. At times, an iron supplement may be necessary to help increase and stabilize iron levels.
At the Department of Food and Nutrition, at Punjab Agricultural University in India, researchers studied the effects of iron supplementation on the physical work capacity of young women. Two groups of 15 female students, both anemic and aged 16 to 20 years old, were created. Participants from the first group were given 60 mg of iron, plus 100 mg of vitamin C to improve iron absorption, for six to nine months. The second group, who were also energy deficient, were given iron and specialized diets for three months. At the end of three months, the anemic and energy deficient women had shown great improvements, especially in their ability to exercise and work for longer periods of time. By the end of the nine months, women from both groups had gained weight and raised their iron and hemoglobin levels to the normal range. The researchers believe low iron coupled with poor diet has a greater adverse effect on the women’s physical work capacity than either low energy or iron deficiency alone.
Sources: Food Nutr Bull 2002 Mar;23(1):57-64; Leslie Beck’s Nutrition Encyclopedia by L Beck, Prentice Hall:2001