Anaemia: Causes, Symptoms, and Treatment

What is Anaemia?

Anaemia develops when there are a low number of red blood cells in circulation, causing oxygen levels to drop and symptoms such as shortness of breath, fatigue, and pale skin.

There are several different types of anaemia, some can be inherited from your parents while others may be caused by a poor diet. Common examples include:

• Iron deficiency anaemia

  The most common form of anaemia worldwide that’s caused by low iron levels^[1]. Iron is critical for the production of haemoglobin, the protein in red blood cells responsible for transporting oxygen around the body.

• Vitamin B12 deficiency anaemia

  A condition that affects the body’s ability to produce healthy red blood cells because of a lack of vitamin B12. It is common amongst people who follow a vegan or vegetarian diet because B12 is exclusively found in animal products^[2].

• Hemolytic anaemia

  This type of anaemia results from red blood cells being destroyed faster than they are made^[3]. There are several causes including medications, autoimmune conditions, inherited disorders such as sickle cell disease and thalassaemia^[4].

According to The National Institute for Health and Care Excellence (NICE) around 3% of men and 8% of women are affected by iron deficiency anaemia^[5]. A study published in 2021, found that 52% of patients admitted to hospital were anaemic on arrival while 16% acquired anaemia during a hospital stay^[6].

Women of childbearing age, 15 to 49 years, are commonly at risk of deficiency because of blood loss experienced during their periods and pregnancy^[7]. From research we carried out earlier in the year, women aged 18 to 29 are the group most likely to be iron deficient, with average ferritin levels 27% lower than average. In men, ferritin levels are more likely to fall within a healthy range. Our research found that 90% of men were within a healthy ferritin range compared to 87% of women.

Anaemia symptoms can make you feel unwell or affect your day-to-day life, but if left untreated, anaemia can be serious, leaving you at risk of complications affecting your heart or lungs or susceptible to infection^[8].

Causes of Anaemia

Anaemia can be caused by a variety of factors, including:

• Iron deficiency: Iron is essential for the production of haemoglobin, and a lack of iron in the diet or an inability to absorb iron can lead to iron deficiency anaemia.

• Vitamin deficiency: Vitamins such as folate, vitamin B12, and vitamin C are also important for red blood cell production. A deficiency in any of these vitamins can lead to anaemia.

• Over-exercise: Iron deficiency is common amongst athletes who take part in endurance sports, particularly among women. High-intensity or endurance exercise can contribute to anaemia by increasing the breakdown of red blood cells, blood loss caused by microscopic lesions that occur during exercise, and through the initiation of pro-inflammatory pathways^[9].

• Chronic diseases: Certain chronic diseases, such as kidney disease, cancer, and HIV/AIDS can affect the body’s ability to produce red blood cells.

• Blood loss: Anaemia can also be caused by blood loss, such as from heavy menstrual periods, surgery, giving birth, or injury.

• Blood donation: Giving blood can cause iron losses of up to 240 mg per session^[10]. Consuming iron-rich foods like green leafy vegetables or lean red meat leading up to and after your donation can help keep you feeling well^[11].

• Inherited disorders: Some inherited disorders, such as sickle cell anaemia and thalassemia, can affect the production of haemoglobin.

• Pregnancy: Pregnant women may develop anaemia due to an increased need for iron and other nutrients.

• Medication: Some medications, such as chemotherapy drugs and certain antibiotics, can affect red blood cell production and lead to anaemia.

Can stress cause anaemia?

Yes, stress can contribute to the onset of anaemia because it can have a significant impact on our mental and physical health. For example, during pregnancy, maternal stress may contribute to iron deficiency anaemia^[12] while animal studies have found that psychological stress may contribute to a reduction in serum and bone marrow iron and in red blood cell production^[12].

Although more research is needed, one of the theories about how stress causes anaemia is that stress affects our diet. When stressed some people may overeat while others may not eat much at all and that can lead to malnutrition, a common cause of iron deficiency anaemia.

Symptoms of Anaemia

Anaemia can affect the whole body because it reduces the amount of oxygen being carried to the body’s tissues. The lack of oxygen-rich blood can leave you feeling weak and tired as well as cause headaches, dizziness, and pale skin.

Depending on the underlying cause and severity of anaemia, the symptoms can vary from person to person, but the common signs include:

• Fatigue and weakness

• Shortness of breath

• Dizziness or lightheadedness

• Headaches

• Pale skin

• Heart palpitations (noticing your heartbeat)

• Cold hands and feet

• Irregular heartbeat

• Restless legs syndrome

• Poor sleep

• Weak and damaged hair

• Difficulty concentrating or thinking clearly

• Sore tongue

• Vision issues

• Anxiety and depression

• Reduced appetite

Does anaemia make you cold?

Yes, anaemia can make your hands and feet cold because of poor circulation. When you are anaemic, the amount of oxygen reaching the body’s tissues is reduced because less blood reaches the extremities, making you feel cold.

Treatment and Prevention

Although it can be serious, there is treatment available for anaemia to help correct your blood levels.

Treatment for anaemia depends on the underlying cause but can include:

• Dietary changes

  If your diet is lacking in specific vitamins and minerals, such as iron, vitamin B12, or folate, it can leave you at an increased risk of deficiency and anaemia. Therefore, it is important to include iron and B12-rich food sources like dark leafy green vegetables, lean red meat, seafood, and lentils in your diet to keep your levels topped up^[14].

• Supplements

  If anaemia is caused by a nutrient deficiency, an iron, B12, or folate supplement, may be prescribed to help bring your levels to within a normal range.

• Infusions and transfusions

  In some cases, treatments such as iron infusions or blood transfusions may be necessary to correct iron levels or increase the number of red blood cells in circulation.

• Treating underlying conditions

  If anaemia is caused by an underlying medical condition, treating it may help to restore the red blood cell count.

• Lifestyle changes

  As well as eating a healthy, balanced diet, other lifestyle factors may need to be addressed to treat or prevent anaemia, such as ensuring you do not over-exercise, factoring in rest periods, limiting alcohol intake, quitting smoking, and managing health conditions.

How to prevent anaemia

1. Pair iron-rich foods with vitamin C

   Vitamin C is important for helping the body to absorb iron. So, pairing iron-rich foods like dark, green leafy veg with foods such as oranges, strawberries, tomatoes, or lemon juice will encourage your body to extract the iron from food^[15].

2. Consider supplements

   If you follow a vegan or vegetarian diet, you are at a greater risk of vitamin B12 deficiency because the nutrient is not made by plants^[16]. So, because vitamin B12 is predominantly found in animal-based sources, it may be necessary to supplement your diet to reduce the risk of deficiency.

3. Avoid tea and coffee at meal times

   Drinks like tea, coffee, beer, cider, and wine contain tannins and phosphates and should be avoided at mealtimes. That’s because tannins can prevent the absorption of iron, especially non-haem iron found in plant-based foods^[17]. Ideally, you should wait 30 minutes to 1 hour before consuming tea after eating a meal. If you are thirsty while you are eating, consider drinking water or maybe a glass of orange juice to promote iron absorption.

4. Avoid over-exercising

   Intense or rigorous training can increase the risk of exercise-induced anaemia, particularly as iron can be lost through sweating, blood loss, and increased red blood cell breakdown^[18]. Therefore, it is important to assess the intensity and frequency of your exercise routine and factor in adequate rest periods to allow your body to recover and replenish.

5. Increase iron intake during menstruation

   Some research claims that up to 90% of women who experience heavy periods are deficient in iron and up to 60% are anaemic^[19]. Therefore, increasing your iron intake during menstruation or considering a daily iron supplement may increase haemoglobin levels and reduce the risk of iron deficiency and anaemia^[19].

If you are experiencing any of the symptoms of anaemia or are concerned your test result suggests you are anaemic, you should contact your GP. They will discuss your symptoms and your current health and lifestyle with you and may carry out further tests to identify the cause of your symptoms.