What is iron-deficiency anemia?
Iron-deficiency anemia is a blood disorder that affects your red blood cells. It’s the most common form of anemia. It happens when your body doesn’t have enough iron to make hemoglobin, a substance in your red blood cell that allows them to carry oxygen throughout your body. As a result, iron deficiency may cause you to feel short of breath or tired. These symptoms develop over time. When iron deficiency is diagnosed, you may be prescribed iron supplements. Healthcare providers will also ask questions and do tests to determine why you developed iron deficiency.
How does iron-deficiency anemia affect my body?
Iron-deficiency anemia symptoms happen over time. Initially, you may have low iron and feel fine or have symptoms that are so mild you don’t notice them. Left untreated, however, iron-deficiency anemia can make you feel tired and weak. You may notice pale skin and cold hands and feet. Iron-deficiency anemia can also cause you to feel dizzy or lightheaded. Occasionally, it can cause chest pain, a fast heartbeat and shortness of breath. Iron deficiency can cause you to have unusual cravings for non-food items such as ice, dirt or paper.
How does iron-deficiency anemia develop?
Normally, your body brings in a steady flow of iron from the food you eat. Your body stores excess iron so it’s available as needed to make hemoglobin. Iron-deficiency anemia develops when your body uses the iron stores faster than they can be refilled, or when the flow of iron into your system has slowed. This occurs in three stages:
- First stage: Iron stores are depleted. In this stage, the supply of iron to make new hemoglobin and red blood cells is dwindling but hasn’t yet affected your red blood cells.
- Second stage: When iron stores are low, the normal process of making red blood cells is altered. You develop what’s called iron-deficient erythropoiesis, sometimes called latent iron deficiency. Erythropoiesis is the medical term for the process of producing new red blood cells. In this stage, your bone marrow makes red blood cells without enough hemoglobin.
- Third stage: Iron-deficiency anemia develops because there isn’t enough iron to make hemoglobin for red blood cells. In this stage, the hemoglobin concentration will drop below the normal range. This is when you may begin noticing iron-deficiency anemia symptoms.
Who’s likely to develop iron-deficiency anemia?
Almost anyone can develop iron-deficiency anemia. That said, women who have menstrual cycles or who are pregnant or breastfeeding are more likely to develop iron-deficiency anemia than women who have gone through menopause or men. Here are other groups of people who have an increased risk of developing iron-deficiency anemia:
- Some infants between ages 6 months and 12 months: Babies are born with iron they received from the person who carried them through gestation. That iron supply runs out after four to six months. Babies who are breastfed only or drink unfortified formula may not get enough iron.
- Children between ages 1 year and 2 years: Many times, young children who drink a lot of cow’s milk may not get enough iron.
- Teenagers: Growth spurts may use up iron reserves more quickly, causing iron deficiency.
- Adults over age 65: Older people may not get as much iron as they need because they’re eating less food.
- Individuals with certain chronic medical conditions, bone marrow disorders or autoimmune disorders.
Symptoms and Causes
What is the most common cause of iron-deficiency anemia?
Losing blood is the most common reason people develop iron-deficiency anemia. Some common reasons include:
- Bleeding in your gastrointestinal (GI) tract, which may cause bright red blood, or dark, tarry or sticky appearing stool. Ulcers, polyps, and colon cancer are common medical conditions that cause GI tract bleeding. Some people develop GI tract bleeding after regular long-term use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen.
- Bleeding in your urinary tract.
- Blood loss due to an injury or surgery.
- Heavy menstrual periods.
- Frequent blood donation.
- Frequent blood tests. This is especially true for infants and small children who have many blood tests.
What are other ways that people develop iron-deficiency anemia?
People can develop iron-deficiency anemia because they don’t get enough iron from food or they have conditions that limit the amount of iron their bodies absorb.
What conditions make it hard for my body to absorb iron?
There are several reasons why your body may not absorb iron, including:
- You have an intestinal or digestive condition like celiac disease, autoimmune gastritis, or inflammatory bowel disease like ulcerative colitis, or Crohn’s disease.
- You have a Helicobacter pylori infection of your stomach.
- You’ve had gastrointestinal surgery, including weight loss surgery, that prevents your body from absorbing enough iron. For example, people who’ve had gastric bypass surgery or a gastrectomy may develop iron-deficiency anemia.
- You have certain rare genetic conditions that disrupt your body’s ability to absorb iron.
What are the symptoms of being deficient in iron?
Iron-deficiency symptoms develop over time and may initially be mild but can worsen over time if not treated. Common iron-deficiency symptoms include:
- Shortness of breath (dyspnea).
- Chest pain.
- Difficulty concentrating.
- Pica (a condition in which people crave non-food items like ice, chalk, paint, clay or starch).
- Restless legs syndrome.
What are common signs of iron-deficiency anemia?
Some common signs you may have this condition include:
- Your nails are brittle or spoon. This is a condition called koilonychia. Your nails look concave, like spoons, instead of growing flat.
- You have cracks at the corners of your mouth.
- You have pale skin, or your skin is paler than usual.
- Your tongue hurts or feels sore.
- Your hands feel cold to others.
Diagnosis and Tests
How do healthcare providers diagnose iron-deficiency anemia?
Iron-deficiency anemia is diagnosed with blood tests. If you have iron-deficiency anemia, your healthcare provider may do additional tests to find the cause. Steps your healthcare provider might take to diagnose iron-deficiency anemia include:
- They may examine your red blood cells under a microscope. If you have iron-deficiency anemia, your red blood cells will be pale instead of bright red and smaller than usual.
- They’ll measure iron levels in your blood.
- They’ll measure the amount of transferrin in your blood. Transferrin is the protein that carries iron.
- They’ll measure the amount of ferritin in your blood. Ferritin is a protein that stores iron.
- They may recommend a colonoscopy or other testing to determine why your iron is low.
Management and Treatment
How do you fix iron-deficiency anemia?
Iron deficiency can be treated with iron supplements, usually as pills and sometimes with an IV. Your healthcare provider will try to identify why you’re low in iron. Most of the time, people have iron-deficiency anemia because they’re losing blood or they’re not absorbing iron in their diet. Healthcare providers treat iron-deficiency anemia by diagnosing and, if possible, treating the underlying cause while treating the iron deficiency.
If I have iron-deficiency anemia, will my healthcare provider prescribe iron supplements?
Everyone’s situation may be a bit different. Your healthcare provider may prescribe iron supplements to restore iron lost from excessive bleeding or if you’re not getting enough iron from food. If you have a condition that keeps you from absorbing iron, they may prescribe intravenous (IV) iron supplements.
What are iron supplement side effects?
Sometimes, iron supplements can cause constipation or make your poop look dark or black. If you’re having trouble with constipation, your healthcare provider will have suggestions for ways to soften it.
How soon will I feel better after taking iron supplements?
It can take three to six weeks before iron supplements begin building up your iron reserves. Your healthcare provider will monitor your iron levels and let you know when your iron levels have improved. Even then, they may recommend taking iron supplements for at least six months so your body can replenish its iron stores.
How can I reduce my risk of developing iron-deficiency anemia?
Most people develop iron-deficiency anemia because they’re losing blood or not absorbing it from their diet. If you think you have these issues, ask your healthcare provider what you can do to avoid iron-deficiency anemia.
I don’t have any underlying conditions. What I can do to prevent iron-deficiency anemia?
You can reduce your risk by eating an iron-rich diet. Here are some iron-rich food groups to consider:
- Legumes: Peas, beans, tofu and tempeh.
- Breads and cereals: Whole wheat bread, enriched white bread, rye bread, bran cereals and cereals with wheat.
- Vegetables: Spinach, broccoli, string beans, dark leafy greens, potatoes, cabbage, Brussels sprouts and tomatoes.
- Protein: Beef, poultry, eggs, liver and fish, including shellfish.
- Fruit: Figs, dates and raisins.
I follow a vegan or vegetarian diet. What should I do to boost my iron intake?
If you follow a vegan or vegetarian diet, look for iron-fortified breads and cereals. There are several non-meat options for boosting your iron intake, like beans, tofu, dried fruits and dark leafy greens. You may want to take an iron supplement. Ask your healthcare provider about appropriate iron supplements so you don’t overload on iron.
Outlook / Prognosis
What can I expect if I have iron-deficiency anemia?
Healthcare providers typically treat iron-deficiency anemia by prescribing iron supplements and suggesting ways you can add iron to your diet. There are times, however, when iron deficiency anemia is a symptom of a serious medical condition. You may be losing blood or your body can’t absorb iron. If that’s your situation, your healthcare provider will focus on treating the condition. Your healthcare provider is your best resource for information.
When should I see my healthcare provider?
Depending on your situation, you should see your healthcare provider regularly so they can monitor your iron levels and your overall health. You might see your healthcare provider every three months for a year or longer.
A note from Cleveland Clinic
We all have days when our daily responsibilities outweigh the amount of energy we have to get things done. But if you have feelings of fatigue that you just can't shake, talk to your healthcare provider. They’ll find out what’s draining your energy. Iron-deficiency anemia symptoms develop over time. Left untreated, iron-deficiency anemia can cause serious medical issues. Fortunately, most people who have iron-deficiency anemia feel better after taking iron supplements.
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