Causes and Types of Anaemia

Anaemia is a condition where your blood has fewer red blood cells than normal. Red blood cells contain haemoglobin, which carries oxygen from your lungs to the rest of your body. As a result, when you have anaemia, your body does not get enough oxygen, making it harder to do everyday activities. There are several different types of anaemia, each with its own cause:

Causes of Anaemia

Anaemia occurs due to many reasons, including:

1. Iron deficiency: This is the most common type of anaemia. It happens when there isn't enough iron in the diet to make healthy red blood cells. If you don't eat enough iron-rich foods like meat, poultry, fish, cooked oysters, dark green leafy vegetables, fortified cereals, and beans, you can become iron-deficient. Iron deficiency anaemia may also occur if your body doesn't absorb iron well, such as during pregnancy or after surgery.

2. Vitamin B12 deficiency: A lack of vitamin B12 (cobalamin) can lead to megaloblastic anaemia, another type of anaemia. Vitamin B12 helps your body produce red blood cells. If your diet lacks vitamin B12 from sources like animal products, such as meat, dairy products, shellfish, eggs, and some breakfast cereals, you can develop this form of anaemia.

3. Folic acid deficiency: Folic acid (folate) is a nutrient found naturally in some foods. Folate helps your body produce and maintain new cells, especially red blood cells. Like vitamin B12, folic acid plays an important role in the production of DNA, which is needed for cell division. Therefore, low levels of folic acid can lead to anaemia. Foods high in folic acid include fruits, vegetables (particularly leafy greens), nuts, seeds, legumes, and some fortified foods.

4. Disease: Certain diseases can affect your bone marrow, preventing it from producing enough red blood cells. Examples include kidney disease, cancer, HIV, rheumatoid arthritis, and lupus. Blood loss through bleeding disorders, ulcers, colon polyps, colorectal cancer, or heavy menstruation can also lead to anaemia.

5. Pregnancy: Pregnant women require additional amounts of iron to support their growing baby. Many pregnant women may experience mild anaemia because of this increased need. Pregnant women are more likely to need extra folic acid (vitamin B9).

Types of Anaemia

There are various types of anaemia based on their causes:

1. Microcytic anaemias: These involve small red blood cells. They usually result from iron deficiency, thalassemias, or sideroblastic anaemia.

2. Macrocytic anaemias: These involve large red blood cells. They are often caused by a lack of vitamin B12 or folic acid, or by certain medications.

3. Normocytic anaemias: These involve red blood cells that are a normal size. They can result from blood loss, kidney failure, liver disease, cancer (such as leukemia), or drugs affecting the immune system.

4. Hemolytic anaemias: These arise from premature destruction of red blood cells.

Many people who have anaemia feel tired and weak all the time. They might be dizzy or short of breath. When you have anaemia, even simple things like climbing stairs can leave you out of breath. In children, poor growth and development may be signs of anaemia. If left untreated, anaemia can worsen and lead to serious health problems.