Iron deficiency anemia

GEETA KHURANA  helps us understand the most common type of anemia.

Iron-deficiency anemia is the most common type of anemia. The term “anemia” usually refers to a condition in which your blood has a lower than normal number of red blood cells. Red blood cells carry oxygen and remove carbon dioxide (a waste product) from your body. Anemia can also occur if your red blood cells don’t contain enough hemoglobin. Hemoglobin is an iron-rich protein that helps carry oxygen to your body. Iron-deficiency anemia usually develops over time if your body doesn’t have enough iron to build healthy red blood cells. Without enough iron, your body starts using the iron it has stored. Soon, the stored iron gets used up. After the stored iron is gone, your body makes fewer red blood cells. The red blood cells it does make will have less hemoglobin than normal.

 

Causes

Iron deficiency could be because of many non nutritional reasons such as genetic disorders, bleeding ulcers or hemorrhoids, gastrointestinal bleeding caused by aspirin or related drugs, frequent blood donations, colon cancer etc, but it can also be caused by lack of dietary iron especially in vegetarians.

Women are especially prone to iron deficiency because of repeated blood loss during menstruation. Pregnancy also places extra iron demands on women since iron is needed to support the added blood volume, the growth of the fetus and blood loss during childbirth.

Symptoms

Fatigue, lethargy, weakness, poor concentration, and impaired immune function.

Another peculiar symptom of anemia called pica is the desire to eat unusual things such as ice, clay, cardboard, paint or starch.

Advanced anemia may also result in lightheadedness, headaches, ringing in the ears (tinnitus), irritability, pale skin, unpleasant sensations in the legs with an uncontrollable urge to move them (restless legs syndrome).

 

Sources of iron

Iron occurs in two forms in foods, heme and nonheme. Heme iron is found only in foods derived from the flesh of animals, such as meats, poultry and fish. Heme iron is so well absorbed that it contributes significant iron to the body. On average, heme iron is about 23% bioavailable. “Bioavailable” in this situation means that the iron can successfully make its way from the food into our bloodstream. This 23% number for heme iron, however, is only an average. In practice, the amount of heme iron we absorb is highly variable. Food cooking methods and presence of calcium have a significant impact on bioavailability of heme iron.

Nonheme iron is found in both plant and animal foods. The rates of absorption of nonheme iron are lower than heme iron. Moreover, sources of nonheme iron often contain phytates, which bind to iron and carry it through the digestive tract unabsorbed.

* Liver extracts from beef (bovine) are a rich natural source of many vitamins and minerals, including iron. Liver extracts provide the most absorbable form of iron – heme iron – and other nutrients critical in building blood, including vitamin B12 and folic acid. Liver extracts can contain as much as 3 – 4 mg of heme iron per gram.

* Other red meats including beef, pork and lamb.

* Seafood such as oysters, clams, tuna, salmon, shell fish, sardines and shrimp, etc

* Chicken and turkey

* Egg yolk

* Green leafy vegetables such as spinach, mustard, mint, coriander, bok choy.

* Other vegetables such as including broccoli, Swiss chard, asparagus, parsley, watercress, Brussels sprouts.

* Whole wheat bread, wheat germ and oats.

* Some breakfast cereals, pastas, breads, and grains are enriched with iron. But you need to check the labels for these.

* Nuts and dried fruits are also considered to have good amounts of iron especially raisins, apricots, dates and prunes.

* Dried beans, molasses and tofu.

Iron absorption enhancers 

* Acidic foods (such as tomato sauce) cooked in an iron pan can leech iron into the food and thus also be a source of dietary iron.

* Vitamin C increases the absorption of iron. Having a glass of orange juice with a vegetarian meal helps to enhance the absorption of iron.

* Vitamin C foods such as oranges, cantaloupe, strawberries, Kiwi fruit, red capsicum, grapefruit, etc.

* Tomatoes, tomato juice and peppers. 

Meat, fish and poultry contain not only the highly bioavailable heme iron, but also a factor called MFP factor that promotes the absorption of nonheme iron from other foods eaten with them. Therefore, addition of meat in the diet along with vegetarian foods enhances the absorption of iron from vegetarian foods.          

Iron absorption inhibitors

* Black tea contains tannins that strongly inhibit the absorption of non-heme iron. In fact, this iron-blocking effect is so effective that drinking black tea can help treat hemochromatosis, a disease of iron overload. Consequently, people who are iron deficient should avoid drinking black tea.

* Fibre is another dietary component that can reduce the absorption of iron from foods.  Foods high in bran fibre can reduce the absorption of iron from foods consumed at the same meal by half. Therefore, it makes sense for people needing to take iron supplements to avoid doing so at mealtime if the meal contains significant amounts of fibre.

* Numerous kinds of phenolic compounds in beverages such as tea and coffee, herbal teas, cocoa and red wine form insoluble complexes with iron and may exist as an “iron-tannin” complex and thus inhibit iron absorption. Therefore, it is advisable to wait an hour after a meal to drink tea.

* Coffee interferes with the absorption of iron. However, moderate intake of coffee may not adversely affect risk of iron-deficiency anemia when the diet contains adequate amounts of iron and vitamin C.

* Phosphates found in carbonated soft drinks can also decrease iron absorption.

* Soy is normally an important part of vegetarian meals as a high quality protein and is an excellent source of the health-promoting phytochemical, genestein. However, most forms of soy (soy flour, soy protein isolate, and tofu processed with calcium sulfate) reduce the absorption of non-heme iron. The inhibitory effect can be largely eliminated by using fermented soy-based products such as soy sauce, (tempeh, natto, miso), iron fortified soy products.

* Oxalates, found in spinach and chocolate, may also decrease iron absorption by forming complexes with the mineral that cannot be absorbed through the digestive tract.