What is iron?

Iron is one of the minerals in the human body. It is one of the components of hemoglobin, the substance in red blood cells that helps blood carry oxygen throughout the body.

If you do not have enough iron, your body cannot make hemoglobin, and you may develop anemia. This is known as iron-deficiency anemia, the most common type of anemia.

Factors that can lower your body's supply of iron include:

  • Blood loss (caused by ulcers, some cancers, and other conditions; and, in women, during monthly periods)
  • A diet that doesn't have enough iron in it
  • An increase in the body's need for iron (for instance, in women during pregnancy)

What are the symptoms of anemia?

There are several symptoms that may occur in all types of anemia. They are:

  • Feeling tired
  • Paleness
  • Difficulty breathing
  • Fast heartbeat
  • Dizziness
  • Headache
  • Feeling cold (including the sensation that your hands or feet are colder than usual)
  • Infections (caused by problems with the immune system)

Who is most likely to develop iron-deficiency anemia?

Anyone can develop iron-deficiency anemia, although the following groups have a higher risk:

  • Women: Blood loss during monthly periods and childbirth can lead to anemia.
  • People over 65, who are more likely to have iron-poor diets.
  • People who are on blood thinners such as aspirin, Plavix®, Coumadin®, or heparin.
  • People who have kidney failure (especially if they are on dialysis), because they have trouble making red blood cells.
  • People who have trouble absorbing iron.

How is anemia diagnosed?

Your healthcare provider can perform blood tests to tell if you have anemia. The type and number of blood tests will depend on what type of anemia your doctor thinks you might have.

The blood tests will measure your hemoglobin and how much iron is in your body. If these levels are low, the doctor can make a diagnosis of anemia.

How is anemia treated?

Your healthcare provider will decide on the proper treatment, depending on the type of anemia and what is causing it.

Your doctor must first find out if the anemia is being caused by a poor diet or a more serious health problem. You can then be treated for both the anemia and its cause.

Iron-deficiency anemia is treated by eating foods that are high in iron, or with oral (taken by mouth) iron supplements.

What foods are high in iron?

The following foods are good sources of iron:

  • Oysters
  • Kidney beans
  • Beef liver
  • Tofu
  • Beef (chuck roast, lean ground beef)
  • Turkey leg
  • Whole wheat bread
  • Tuna
  • Eggs
  • Shrimp
  • Peanut butter
  • Leg of lamb
  • Brown rice
  • Raisin bran (whole grain-enriched cereals)
  • Blackstrap molasses
  • Lentils
  • Beans
  • Spinach

What is oral iron supplementation?

In addition to eating foods that are rich in iron, you may have to take oral iron supplements. There are many different types of oral iron supplements, including pills, capsules, drops, and extended-release tablets. The purpose of oral iron supplementation is to treat your symptoms by increasing the levels of iron and hemoglobin in your body.

You don't need a prescription to buy iron supplements. Working with your doctor, you can choose which type is best for you.

The iron in your body is called "elemental iron." Oral iron supplements contain different amounts of elemental iron. When you choose a supplement, be sure to check the label to see how much elemental iron it contains; a greater amount means that more iron will be absorbed by your body.

What dose of iron is usually prescribed for the treatment of iron deficiency anemia?

Your doctor will tell you how much iron you need to take every day. For the treatment of iron deficiency anemia in adults, 100 to 200 mg of elemental iron per day has been recommended. The best way to take the supplement so that you absorb the greatest amount of iron is to take it in two or more doses during the day. However, extended-release iron products may be taken once a day.

Please note the following:

  • Although the supplements work best on an empty stomach, you may want to take them with food so that they don't upset your stomach.
  • You shouldn't take iron supplements with milk, caffeine, antacids, or calcium supplements. These can decrease the amount of iron that is absorbed.
  • Try to take your iron supplement with vitamin C (for example, a glass of orange juice) to increase absorption.

When will I start to feel better?

When you should start to feel better depends on your particular situation. Normally, it may take from a week to a month (after you start your iron supplement) before you start to feel better. Continue to watch your symptoms and take note of side effects that might be caused by the supplements. If you have any questions or concerns, talk to your healthcare provider.

What are the side effects of oral iron supplements?

Oral iron supplements can cause the following side effects:

How long will I have to take an oral iron supplement?

Your doctor will let you know how long you will have to take the iron supplement. Usually, after your hemoglobin and iron levels are back to normal, you will continue to take the iron supplement for another six months. Afterward, you will have regular blood tests to measure your iron level.

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