Hypochromic Anaemia

Hypochromic anaemia is a blood condition where red blood cells appear paler than normal due to lower levels of haemoglobin, the protein that carries oxygen throughout the body. This condition most commonly occurs because of iron deficiency, though other causes exist, and affects millions of people worldwide, particularly women and young children.

Table of contents

• What is Hypochromic Anaemia?
• What Causes This Condition
• Who is Most Affected
• Signs and Symptoms
• How Doctors Diagnose the Condition
• Treatment Approaches
• Related Blood Disorders

What is Hypochromic Anaemia?

Hypochromic anaemia is a type of anaemia, which means having fewer healthy red blood cells than normal. The term “hypochromic” comes from “hypo” (meaning less) and “chromic” (meaning colour), describing how red blood cells appear paler than usual when examined under a microscope^[2].

This paleness happens because these cells contain less haemoglobin, a protein that gives blood its red colour and carries oxygen to all parts of the body. When haemoglobin levels are low, your body cannot transport enough oxygen to your tissues and organs, which can make you feel tired and weak^[1].

Most hypochromic anaemia also involves microcytic red blood cells, meaning the cells are smaller than normal. Healthcare providers measure this using a test called mean corpuscular volume (MCV). When the MCV is less than 80 femtoliters, the cells are considered microcytic^[6].

Red blood cells contain haemoglobin, which has four chains of proteins and a ring structure that holds iron. Iron is essential for haemoglobin production and is the main carrier of oxygen in your blood. When your body lacks enough iron, it cannot make adequate haemoglobin, leading to this type of anaemia^[1].

What Causes This Condition

The most common cause of hypochromic anaemia is iron deficiency. Your body may not have enough iron for several reasons^[1].

You might not be getting enough iron from the food you eat. This happens when your diet lacks iron-rich foods like meat, fish, beans, and dark green vegetables. Some people’s bodies have trouble absorbing iron from food, even when they eat the right foods. This can occur in conditions like celiac disease (a condition where the body reacts badly to gluten) or infections with certain bacteria^[5].

Blood loss is another major cause. When you lose blood, you also lose the iron it contains. Women who have heavy menstrual periods lose blood every month, putting them at higher risk. Blood loss can also happen inside your body without you knowing it, such as from stomach ulcers, bleeding in the intestines, or cancer in the digestive system^[6].

Sometimes your body needs more iron than usual. Pregnant women need extra iron for their developing baby. People recovering from major injuries or surgery also need more iron as their bodies heal^[1].

Other causes of hypochromic anaemia include inherited blood disorders called thalassemias, which affect how your body makes haemoglobin. Long-term illnesses that cause inflammation in your body, such as cancer, kidney disease, autoimmune diseases like rheumatoid arthritis or lupus, and chronic infections can also lead to this condition^[6].

Less common causes include a rare disorder called sideroblastic anaemia, which affects how your bone marrow makes red blood cells, and long-term exposure to lead^[6].

Who is Most Affected

Hypochromic anaemia, particularly when caused by iron deficiency, is very common worldwide. According to the World Health Organization, about one in four people globally currently has anaemia, with iron deficiency being the main cause^[1].

Women of childbearing age are the most affected group. They lose blood during their monthly periods, which depletes their iron stores. Among pregnant women worldwide, about 41% have anaemia. Among non-pregnant women who have not yet reached menopause, about 30% struggle with anaemia^[1].

Men are generally less likely to develop iron deficiency anaemia because the hormone testosterone helps protect them. However, about 12.7% of adult men around the world still have anaemia^[1].

After women, pre-school-aged children are the next most affected group. This happens mainly because young children’s diets often lack enough iron. While cow’s milk contains more iron than human breast milk, the iron in cow’s milk is harder for the body to absorb and use efficiently^[1].

Signs and Symptoms

In the early stages, hypochromic anaemia can be so mild that you might not notice any symptoms. However, as iron levels drop lower and the anaemia worsens, symptoms become more noticeable^[5].

The most common symptom is extreme tiredness or fatigue. You may feel too tired to manage your daily activities. Many people also experience weakness and feel drained of energy^[6].

You might notice that your skin looks paler than usual. This paleness is especially visible on your palms, in the lining of your eyelids, and under your fingernails and toenails. In people with darker skin, the paleness may be most noticeable in the whites of the eyes and the palms^[5].

Your heart may beat faster than normal, and you might experience palpitations (feeling your heart pounding or racing). Some people feel short of breath, especially during physical activity. Headaches and dizziness are also common^[6].

Other symptoms include feeling irritable or having mood changes. Your hands and feet may feel cold. Some people develop dry skin or skin that bruises more easily than usual^[6].

Changes to your nails can occur. They may lose their pink colour and become pale. In more severe cases, nails can develop a spoon-like shape (curved inward) and become brittle and prone to breaking^[5].

Some people develop unusual cravings to eat things that are not food, such as ice, clay, or flour. This condition is called pica. Others may crave unusual smells, like rubber or cleaning products^[8].

If you or someone in your family experiences these symptoms and they do not go away within two weeks, you should see a doctor. Seek medical attention immediately if you experience severe shortness of breath or dizziness^[5].

How Doctors Diagnose the Condition

To diagnose hypochromic anaemia, your doctor will ask about your medical history and any symptoms you have been experiencing. They will also perform a physical examination^[6].

The main way to diagnose this condition is through blood tests. The most important test is called a complete blood count (CBC). This test measures how many red blood cells you have and checks the level of haemoglobin in your blood. It also measures hematocrit, which is the ratio of red blood cells to the total volume of your blood^[1].

The CBC also provides information about the size of your red blood cells. This measurement is called the mean corpuscular volume (MCV). If your MCV is less than 80 femtoliters, it means your red blood cells are smaller than normal^[6].

Another important test is a peripheral blood smear. For this test, a laboratory technician examines your blood cells under a microscope. They can see if your red blood cells are smaller than normal (microcytic) and paler than normal (hypochromic)^[6].

To find out why you have hypochromic anaemia, your doctor may order additional tests. Iron studies check how your body is storing and using iron. These tests include checking your serum ferritin level, which shows how much iron your body has stored. The total iron-binding capacity (TIBC) test measures how well your blood can carry iron^[6].

It is important not to start taking iron supplements before these tests are done, as this can make it harder to identify the true cause of your anaemia. Treatment should not begin until doctors know what is causing your condition^[4].

If your doctor suspects that blood loss is causing your anaemia, they may order additional tests to find where the bleeding is coming from. These might include tests to check for bleeding in your digestive system^[6].

Treatment Approaches

Treatment for hypochromic anaemia depends on what is causing it. Doctors treat the condition by addressing the underlying cause^[6].

When iron deficiency is the cause, the main treatment is taking iron supplements and improving your diet. Iron supplements help restore your body’s iron levels. Most people take these supplements by mouth, usually in the form of ferrous sulfate tablets. The traditional dose is one 325 mg tablet (containing 65 mg of elemental iron) three times a day, though lower doses may work just as well and cause fewer side effects^[12].

Some people cannot take iron pills because they cause stomach upset, or their bodies cannot absorb iron well from pills. In these cases, doctors may give iron through an intravenous infusion (directly into a vein)^[6].

Improving your diet is also important. Foods rich in iron include red meat, chicken, pork, fish, beans and legumes (like lentils and chickpeas), nuts, and iron-rich vegetables like broccoli, spinach, peas, and tomatoes. Whole grains and fortified cereals also provide iron^[18].

How you pair foods can affect how well your body absorbs iron. Foods high in vitamin C help your body absorb iron better. Good combinations include fish with lemon juice or pasta with tomato sauce. Some studies suggest that cooking in cast iron skillets can increase the iron content of your food^[18].

You should limit certain foods when trying to increase iron absorption. Dairy products like milk, cheese, and ice cream can make it harder for your body to absorb iron. Foods and drinks high in tannins (a natural substance found in plants) can also interfere with iron absorption. These include coffee, black tea, dark chocolate, red wine, and pomegranates. You do not need to avoid these completely, but wait a few hours after eating iron-rich foods before consuming them^[18].

If bleeding is causing your anaemia, finding and stopping the source of bleeding is essential. This might require treatment for conditions like ulcers, or in some cases, surgery^[6].

When hypochromic anaemia is caused by chronic diseases or inflammation, treating the underlying illness is important. In some cases, people may need different types of treatment beyond iron supplements^[6].

While being treated, it is important to rest when you feel tired and to take breaks when symptoms like dizziness occur. Light exercise like walking, swimming, or bicycling can be helpful, but stop immediately if you experience chest pain or severe shortness of breath^[18].

Related Blood Disorders

microcytic hypochromic anemia, green sickness, chlorosis

Several other blood disorders are closely related to hypochromic anaemia or can cause similar symptoms.

Iron deficiency anaemia is the most common cause of hypochromic anaemia. It develops when your body does not have enough iron to make adequate haemoglobin^[6].

Thalassemia is an inherited blood disorder that affects how your body makes haemoglobin. People with thalassemia may have microcytic hypochromic red blood cells similar to those seen in iron deficiency, but their iron levels may be normal or even high^[5].

Anemia of chronic disease can develop in people with long-term illnesses that cause inflammation in the body. Conditions like cancer, chronic kidney disease, inflammatory bowel disease, and chronic infections can interfere with how the body uses iron, leading to anaemia^[6].

Sideroblastic anemia is a rare blood disorder where the bone marrow cannot make normal red blood cells, even though iron is available^[6].

A rare hereditary form called hypochromic microcytic anemia with iron overload is caused by genetic changes that affect how cells transport iron. In this condition, red blood cells cannot access iron properly, leading to anaemia, while unused iron accumulates in the liver and can damage it over time^[3].