Iron deficiency is one of the most common nutritional deficiencies found among Americans. When severe it is called iron-deficiency anemia.
Women of child-bearing age, teenage girls, young children, and people on low incomes are the groups most prone to this problem.
Iron is of great importance to the body. It plays a role in the formation of hemoglobin, which is the substance in red blood cells that carries oxygen to all cells of the body. This process is essential for the production of energy.
Symptoms of iron-deficiency include chronic fatigue and general weakness (that tired, run-down feeling), loss of appetite, irritability, poor resistance to infection, and reduced ability to do any sort of exercise.
The body’s requirement for iron is very small. Why are so many people low in their intake of iron?
Part of the problem lies with our eating habits. There has been a general increase in the consumption of highly processed and convenience foods, many of which are low in iron. Currently more than 60 percent of our calories come from sugars, fat, and alcohol, none of which provide any iron.
Women and teenage girls often are cutting back on calories in order to reduce their weight. Any great reduction of calories also is likely to reduce iron intake.
The average diet provides about 6 milligrams of iron per 1,000 calories. If a woman or teenage girl is on a low-calorie diet, it becomes difficult for her to meet the recommended daily intake of 12 milligrams of iron.
Iron needs are very high when a woman is pregnant or breastfeeding. Pregnancies that are close together may mean that a woman’s iron stores become depleted.
Iron stores of young children may become low once breast milk or iron-containing infant formulas are discontinued unless other good food sources of iron are introduced. Cow’s milk is very low in iron.
Another obstacle to getting enough iron is that while some foods do contain iron, this iron is not in a form that is well absorbed by the body. The body is best able to absorb iron from what is known as heme sources, or meats such as liver and offal meats, beef, lamb, pork, and poultry.
Absorption of iron from plant sources such as breads, cereals, dried beans, and vegetables isn’t as good as from heme sources.
Luckily, one can greatly improve the absorption of iron from these plant sources if a food rich in Vitamin C is included at the same meal. It is good to get into the habit of having at least one serve of fruit, vegetable, or a Vitamin C rich juice with each meal.
Small amounts of meat eaten at a meal also can mean that more iron is absorbed from plant foods eaten at the same meal.
Certain factors may decrease the absorption of iron and make the risk of iron-deficiency anemia greater. These include excessive amounts of bran (two tablespoons of unprocessed bran a day is considered a moderate amount), excessive quantities of tea or coffee, very large intakes of milk, and long-term regular use of aspirin or antacids.
The richest dietary sources of iron are liver and other offal meats such as kidney and heart. Other good sources are meat, poultry, oysters, eggs, nuts, legumes (dried peas, beans, and lentils), whole-grain breads and cereals, dried fruits, and leafy green vegetables such as broccoli, asparagus, and brussels sprouts.
Contrary to popular opinion, spinach is not a good source of iron, as the iron it contains is not well absorbed. Milk and milk products are extremely poor sources of iron, so if cheese is used as the protein source of a meal, it is a good idea to include some iron-rich foods as well.
Because meat is the richest source of well-absorbed iron, vegetarians need to be very careful to include a wide variety of the good plant sources of iron listed above.
Certain people may require iron supplements. Some obstetricians routinely recommend iron tablets to pregnant women, but it is still important that they include iron-rich foods as well.
Before taking an iron supplement, it is advisable to seek advice from your doctor. A routine blood test can show whether or not you are actually deficient in iron. If you aren’t, good food sources of iron are preferable to iron tablets.
Women or teenage girls who have been advised to go on strict weight-control diets could include a one-a-day type of multi-vitamin and mineral supplement as a precaution against deficiency. They also should regularly include rich sources of iron in their diet.
Several steps to reduce the risk of iron deficiency
How is it that athletes and sportspersons, commonly regarded as among the healthiest people in society, so often suffer from iron deficiency?
For some, the reasons are simple. Certain sports, such as ballet and long-distance running, have traditionally demanded a lean physique, and often a strict, high-carbohydrate, low-fat, low protein diet. Unless care is taken, such a regime can easily lead to iron deficiency. But heavy training in itself exerts pressures upon athletes which can deplete iron stores more readily than sedentary life does.
During heavy training, an athlete or sportsperson’s plasma volume — that is the amount of fluid in the blood and in the body — increases, diluting what stores of iron might be present in the red blood cells.
Certain very heavy forms of training can even lead to gastrointestinal bleeding, resulting in a further depletion of iron in the blood. And some sports, particularly those such as running which require the feet to strike the ground repeatedly, can lead to the breaking of tiny capillaries in the feet and joints and the destruction of even more red blood cells.
Athletes and other people who undergo heavy training sessions also lose iron through sweat. It has been estimated that up to 2.5mg of iron can be lost in each liter of sweat. There are several things that athletes and non-athletes alike can do to lessen their risk of developing iron deficiency.
The first, naturally, is to have a diet rich in iron. Vegetarians and people who do not eat much red meat need to be particularly careful since the non-haem iron contained in vegetables and cereals is not absorbed as readily as the haem iron contained in meat, so proportionately greater amounts need to be consumed.
It is worth noting that some iron supplements on the market contain non-haem iron, so the benefit gained from taking these supplements might not be as great as the consumer might suppose.
There are a couple of things that can assist or inhibit the absorption of whatever iron is actually eaten, and these should be kept in mind at mealtimes.
Vitamin C, found in large amounts in citrus fruits, tomatoes, and capsicums, can enhance the absorption of iron in other foods. Some people like to have a small glass of orange juice with their meal, or a wedge or two of tomato, to help kick the absorption process along. The citric acid in fruit juice also assists absorption, as does the lactic acid in milk and, oddly enough, alcohol.
Things which can inhibit iron absorption include tannins (delay drinking that cup of tea for an hour or so after a meal or risk cutting iron absorption by up to 60 percent), the phosvitin found in egg yolks and phytates found in cereals and legumes (this is one reason why the iron from these sources is not absorbed as readily as the iron in meat).
It is ironic that some athletes, in their keenness to improve their personal performance, might actually be limiting their potential by being deficient in iron. And what goes for athletes goes for the rest of us, too. All of us can do without tiredness and lethargy which can result from even moderate iron deficiency.