Anaemia

Anaemia occurs when your body doesn’t have enough healthy red blood cells to carry oxygen throughout your body, leaving you feeling tired, weak, and short of breath. This common blood condition affects millions of people worldwide and can range from mild to severe, but the good news is that most types are treatable.

Table of contents

• What is anaemia?
• Common symptoms
• What causes anaemia?
• Common types of anaemia
• Who is at risk?
• How is anaemia diagnosed?
• Treatment options
• Prevention and lifestyle changes
• Living with anaemia

What is anaemia?

Anaemia is a condition that develops when your blood produces a lower-than-normal amount of healthy red blood cells or when these cells don’t work properly^[1]. Red blood cells carry hemoglobin, an iron-rich protein that attaches to oxygen in the lungs and carries it to tissues throughout the body^[4]. When you have anaemia, your body does not get enough oxygen-rich blood, which is why you may feel tired or weak^[3].

Anaemia is the most common blood disorder and affects more than 3 million people in the United States alone^[2]. Globally, it is estimated that approximately one in three people in the global population are affected^[2]. The condition particularly affects young children, pregnant and postpartum women, and menstruating adolescent girls and women^[5].

Anaemia can be temporary or long-term and can range from mild to severe^[1]. Some forms of anaemia are inherited, meaning you are born with the condition, while others develop during your lifetime^[2]. The condition is not a disease itself but rather a presentation of an underlying problem^[13].

Common symptoms

The symptoms of anaemia depend on the cause and how severe the condition is. Anaemia can be so mild that it causes no symptoms at first, but symptoms usually appear and get worse as the anaemia worsens^[1]. Most patients experience some symptoms when the hemoglobin drops below 7.0 g/dL^[13].

Fatigue — feeling too tired to manage your activities — is the most noticeable anaemia symptom^[2]. Other common symptoms include:

• Weakness
• Shortness of breath
• Dizziness or lightheadedness
• Fast or irregular heartbeat
• Chest pain
• Cold hands and feet
• Headaches
• Pale or yellowish skin, which might be more obvious on white skin than on Black or brown skin^[1]

Less common symptoms of anaemia that are not usually connected to pregnancy include hearing ringing, buzzing or hissing noises inside your head (tinnitus), food tasting strange, feeling itchy, a sore tongue, hair loss, wanting to eat non-food items such as paper or ice (a condition called pica), finding it hard to swallow, painful open sores in the corners of your mouth, nail changes such as spoon-shaped nails, and restless legs syndrome^[14].

When anaemia comes on slowly, the symptoms are often vague, such as tiredness, weakness, shortness of breath, headaches, and a reduced ability to exercise^[8]. When anaemia is acute, symptoms may include confusion, feeling like one is going to pass out, loss of consciousness, and increased thirst^[8].

What causes anaemia?

Many things can cause anaemia. The condition develops when there is not enough iron in your body, when your body cannot make enough red blood cells, when red blood cells are broken down too quickly, or when you lose blood^[3].

Low levels of iron are one of the most common causes of anaemia. Your body needs iron to make hemoglobin, and without enough iron, the body produces fewer and smaller red blood cells^[9]. Bleeding is the most common cause of a lack of iron. You may have heavy menstrual bleeding or bleeding caused by conditions such as ulcers or cancer^[25]. Regular use of aspirin or other anti-inflammatory medicines such as ibuprofen also can cause bleeding in some people^[25].

A lack of iron in your diet also can cause anaemia, especially at times when the body needs more iron, such as during pregnancy, infancy, and the teen years^[25]. Other causes include vitamin deficiencies, particularly vitamin B12 and folate deficiency, which may result from poor dietary intake^[4].

Anaemia can also be caused by chronic diseases. If you have an illness that causes chronic inflammation, it can make it hard for your body to use the iron it needs to make red blood cells^[2]. People with kidney disease may develop anaemia because the kidneys are not making enough of the hormone erythropoietin to signal the bone marrow to make new red blood cells^[4].

Some forms of anaemia are inherited, meaning they are passed down through families. These include conditions like sickle cell anemia, thalassemia, Diamond-Blackfan anemia, and Fanconi anemia^[2].

Common types of anaemia

There are many forms of anaemia, and each has its own cause. Some of the most common types include:

Iron-deficiency anaemia is the most common type. It happens when you do not have enough iron in your body. Iron deficiency is usually due to blood loss but may occasionally be due to poor absorption of iron^[4]. Pregnancy and childbirth consume a great deal of iron and can result in pregnancy-related anaemia^[4].

Vitamin-deficiency anaemia may result from low levels of vitamin B12 or folate (folic acid), usually due to poor dietary intake^[4]. Pernicious anaemia is a condition in which vitamin B12 cannot be absorbed in the gastrointestinal tract; it is an autoimmune condition that prevents your body from absorbing vitamin B12^[2].

Hemolytic anaemia occurs when red blood cells are broken up in the bloodstream or in the spleen. This may be due to mechanical causes such as leaky heart valves or aneurysms, infections, autoimmune disorders, or congenital abnormalities in the red blood cell^[4].

Aplastic anaemia is a rare bone marrow failure disorder in which the bone marrow stops making enough blood cells (red blood cells, white blood cells, and platelets). This occurs as a result of destruction or deficiency of blood-forming stem cells in your bone marrow, particularly when the body’s own immune system attacks the stem cells^[4].

Anaemia of chronic disease can develop if you have an illness that causes chronic inflammation, making it hard for your body to use the iron it needs to make red blood cells^[2].

Who is at risk?

Many people are at risk for anaemia because of poor diet, intestinal disorders, chronic diseases, infections, and other conditions^[4]. The population groups most vulnerable to anaemia include children under 5 years of age, particularly infants and children under 2 years of age, menstruating adolescent girls and women, and pregnant and postpartum women^[5].

Women are at higher risk of iron-deficiency anaemia because of blood loss from their periods and higher blood supply demands during pregnancy^[6]. Women who are menstruating or pregnant and people with chronic medical conditions are most at risk for this disease^[4].

The risk of anaemia increases as people grow older. Older adults have a greater risk of anaemia because they are more likely to have kidney disease or other chronic medical conditions^[6].

If you have any of the following chronic conditions, you might be at greater risk for developing anaemia: rheumatoid arthritis or other autoimmune disease, kidney disease, cancer, liver disease, thyroid disease, or inflammatory bowel disease such as Crohn disease or ulcerative colitis^[4].

Low- and lower-middle income countries bear the greatest burden of anaemia, particularly affecting populations living in rural settings, in poorer households and who have received no formal education^[5]. Globally, it is estimated that 40% of all children aged 6–59 months, 37% of pregnant women and 30% of women 15–49 years of age are affected by anaemia^[5].

How is anaemia diagnosed?

To diagnose anaemia, your health care provider is likely to ask you about your medical and family history, do a physical exam, and order blood tests^[11].

The main test is a complete blood count (CBC). A CBC is used to count the number of blood cells in a sample of blood. For anaemia, the test measures the amount of red blood cells in the blood, called hematocrit, and the level of hemoglobin in the blood^[11]. It is diagnosed when a blood test shows a hemoglobin value of less than 13.5 gm/dl in a man or less than 12.0 gm/dl in a woman^[4]. Normal values for children vary with age^[4].

Typical adult hemoglobin values are generally 14 to 18 grams per deciliter for men and 12 to 16 grams per deciliter for women. Typical adult hematocrit values vary among medical practices but are generally between 40% and 52% for men and 35% and 47% for women^[11].

Your provider may also order a test to show the size and shape of the red blood cells. This looks at the size, shape and color of the red blood cells^[11]. If you get a diagnosis of anaemia, you might need more tests to find the cause. Sometimes, it can be necessary to study a sample of bone marrow to diagnose anaemia^[11].

Treatment options

Treatment for anaemia depends on the type you have and how serious it is. Your treatment will depend on its cause^[3]. Establishing the cause of anaemia permits selection of a specific and effective therapy^[16].

Iron supplements are commonly prescribed if the blood test shows your red blood cell count is low. You’ll need to take them for about 6 months^[14]. Drinking orange juice after you’ve taken a tablet may help your body absorb the iron^[25]. Some people get side effects when taking iron tablets like constipation or diarrhea, tummy pain, heartburn, feeling sick, or darker than usual poo^[14].

Vitamin supplements may be needed. In consultation with healthcare professionals, consider incorporating iron supplements or vitamin B12 supplements into your routine^[12]. People who have trouble absorbing vitamin B-12 from food might need vitamin B-12 shots^[11].

Dietary changes are important. If your diet is partly causing your iron deficiency anaemia, your healthcare provider will tell you what foods are rich in iron so you can eat more of them^[14]. This includes dark-green leafy vegetables like watercress and curly kale, cereals and bread with extra iron in them (fortified), meat, dried fruit like apricots, prunes and raisins, and pulses (beans, peas and lentils)^[14].

Blood transfusion is a common, safe medical procedure in which healthy blood is given to you through an intravenous (IV) line. Blood transfusions replace blood that is lost through surgery or injury, or provide blood if your body is not making it properly^[12].

Medicines may be prescribed to help your bone marrow make more red blood cells. If your anaemia is caused by an autoimmune disease, you may need medicines to suppress your immune system^[12].

Surgery may be useful to control bleeding that is causing anaemia, most commonly bleeding from the gastrointestinal tract, uterus, or bladder^[16]. In some inherited conditions like hereditary spherocytosis and hereditary elliptocytosis, splenectomy (surgical removal of the spleen) has been advantageous^[13].

For some types of mild to moderate anaemia, treatment may be as simple as dietary changes and supplements. For other types, more intensive treatments like blood transfusions or bone marrow transplants may be necessary^[3].

Prevention and lifestyle changes

Some forms of anaemia can be prevented by eating a healthy diet. A well-balanced diet for anaemia includes whole grains, animal protein such as chicken, beef, pork and fish, nuts, beans and legumes, and iron-rich fruits and vegetables like broccoli, collard greens, peas, raisins, spinach, strawberries, and tomatoes^[20].

Foods high in vitamin C allow easier iron absorption. This makes fish with lemon juice, marinara sauce, and enriched pasta beneficial pairings for people with anaemia^[20]. A study found that cooking food in a cast iron skillet increases its iron content^[20].

You should limit or avoid certain foods and drinks that can make iron absorption harder. Despite being high in calcium, milk and dairy products like ice cream, butter, and cow’s milk can make iron absorption harder^[20]. Tannin has the same effect. Examples of high-tannin foods and drinks include pomegranate, dark chocolate, coffee, black tea, and red wine^[20]. You do not have to forgo these completely, but wait a few hours after eating an iron-rich meal to consume them^[20].

Staying adequately hydrated is crucial for overall health and can positively impact anaemia. Water supports the circulatory system, ensuring that red blood cells can efficiently transport oxygen throughout the body^[21].

Chronic stress can contribute to anaemia and worsen its symptoms. Incorporate stress-reducing activities such as meditation, yoga, or deep breathing exercises into your daily routine to promote overall well-being^[21].

Exercise is an effective way to reduce the symptoms of anaemia, but take it easy and do not push through symptoms when working out. Stop immediately if dizziness, chest pain, and shortness of breath occur^[20]. Low-impact aerobics like walking, swimming, dancing, bicycling, and resistance training like squats and planks may be recommended^[20].

Living with anaemia

Living with anaemia means making certain adjustments to manage your symptoms and maintain your health. Take time to rest, which involves getting enough sleep every night and resting as needed. Anaemia can make you feel fatigued, weak, and dizzy. For your safety, always take breaks when symptoms flare up^[20].

Follow your healthcare provider’s advice about taking your medicines. If your doctor recommends iron pills, take them as directed: try to take the pills on an empty stomach about 1 hour before or 2 hours after meals. But you may need to take iron with food to avoid an upset stomach^[25]. Do not take antacids or drink milk or caffeine drinks (such as coffee, tea, or cola) at the same time or within 2 hours of the time that you take your iron, as they can make it hard for your body to absorb the iron^[25].

Keep iron supplement tablets out of the reach of children. An overdose of iron in a young child can be fatal^[14].

It’s important to attend all follow-up appointments with your healthcare provider. Your doctor may carry out repeat blood tests over the next few months to check that your iron level is getting back to normal^[14]. Follow-up care is a key part of your treatment and safety^[25].

Call your doctor if you have new or increased shortness of breath, if you are dizzy or light-headed or feel like you may faint, if you have new or worse nausea and vomiting, if your fatigue and weakness continue or get worse, or if you have any abnormal bleeding^[25].

Some types of anaemia have mild symptoms that ease with treatment, while other types are more serious and may cause lifelong medical issues. However, with proper treatment and management, many people with anaemia can lead healthy, active lives^[2].