What Is Iron-Deficiency Anaemia?
This is a health condition caused by a shortage of iron in the body. In the majority of cases it is easily treated, but it is nonetheless the foremost diagnosed category of anaemia. The levels of iron in the body are able to be decreased by means of blood loss, not consuming enough iron from your diet or problems related to absorption, which prevent iron being absorbed from food.
Anaemia is an umbrella term employed for a number of conditions that arise as a result of a low proportion of red blood cells or a shortage of haemoglobin in the red blood cells. Haemoglobin is a protein which is rich in iron, it is the red component of red blood cells and it plays a vital role in the transportation of oxygen by way of the lungs to other areas of the body. An individual with anaemia will have a shortage of haemoglobin in the blood, which means that not enough oxygen is being transported around the body. The red blood cells are also involved in the removal of carbon dioxide from the cells.
Red blood cells, otherwise known as erythrocytes or RBCs, are of equal size and resemble a doughnut shape without the central hole. They are created in the bone marrow and usually live for around 120 days. At the time they expire the iron is taken from the haemoglobin component and recycled to produce new red blood cells.
Numerous forms of anaemia exist but iron deficiency anaemia is the one most commonly diagnosed. The main reasons for anaemia are decreased manufacture of red blood cells, loss of blood and conditions that result in damage of red blood cells. There are other forms of blood cells found in the body, including white blood cells (responsible for fighting infections and disease) and platelets (involved in the blood clotting process). Some forms of anaemia cause a lack each type of blood cell. Anaemia is most commonly associated with feeling very tired because there is a shortage of oxygen travelling around the body.
Iron deficiency anaemia
The condition comes into being when there is insufficient iron within the body to create haemoglobin. This, in turn, causes a shortage of haemoglobin in the red blood cells, which decreases the amount of oxygen transported by way of the lungs to other areas in the body. We intake iron from foods such as shellfish and meat and you can also buy food fortified in iron, including breakfast cereals. The body needs to take in a stable contribution of iron in order to produce strong red blood cells and maintain stable levels of haemoglobin to ensure the supply of oxygen around the body.
There are three causes of low levels of iron in the body, including:
- Blood loss: this can be caused by a health condition, injury or accident.
- Iron shortage in the diet.
- Problems with absorbing iron from food.
Iron deficiency anaemia can also happen when the body requires greater levels of iron (during pregnancy, for example).
How does iron deficiency anaemia affect the body?
Iron deficiency anaemia affects people in different ways; it can be mild or severe and symptoms will vary according to the harshness of the condition. Mild cases usually cause tiredness, lethargy and generally feeling unwell, while severe cases can cause weakness, fatigue and heart problems. The condition can be particularly serious in pregnant women and children.
Children can suffer from developmental delay, delayed growth and heart murmurs. There is also evidence to suggest that children with the condition hold an elevated danger of developing infections, lead poisoning and behavioural problems.
Iron deficiency anaemia in women can cause complications during pregnancy, including a higher risk of premature birth and a baby being born underweight. Babies that have low birth weight have a heightened chance of developing infections and illnesses, and they may also experience delayed growth and development.
When oxygen is lower in the body than normal, this can cause problems for the heart. This is because the heart is forced to function at a higher rate than usual to pump blood around the body and ensure oxygen reaches all parts of the body. This can increases strain on the heart and contribute to irregular heartbeats, an enlarged heard, chest pain and, in extreme cases, heart failure.
Important information about iron deficiency anaemia
Of all the forms of anaemia, iron deficiency anaemia is most often diagnosed and is one of the main nutritional problems. The condition is most common among pregnant females, young children and females of an age appropriate for having children (aged between 20 and 35). Around 50 percent of pregnant women suffer from the condition and 20 percent of females of an age appropriate for having children.
Iron deficiency anaemia can be serious if left untreated. However, it is usually simple to treat and the outlook is positive. In most cases the cause can also be effectively treated.
What are the causes of iron deficiency anaemia?
The condition is caused by a shortage of iron in the body, which can be caused by the following:
- Blood loss (this may be a result of injury, trauma or the complication of a disease).
- Problems with absorbing iron from food.
- Low levels of iron in the diet: if you do not take in enough iron from your diet, iron levels will be too low.
Iron deficiency anaemia can also develop at times when the body requires increased levels of iron, the most common example being pregnancy.
Loss of iron by means of blood loss
Generally speaking if blood is lost then this results in iron being lost. If a person loses a high proportion of blood, the body may not have sufficient iron reserves and consequently incur iron deficiency anaemia. There are many reasons why blood may be lost, including:
- Menstruation in girls and women.
- Fibroids in the uterus (these can bleed and cause blood loss gradually).
- Bleeding ulcers or polyps.
- Colon cancer.
- Bleeding from the urinary tract.
- Hookworm infection.
- Using non-steroidal anti-inflammatory medication on a regular basis.
These tend to result in gradual blood loss.
Blood can also be lost quickly and suddenly in the following circumstances:
- Accidents and injuries.
- Drawing blood on a regular basis.
Shortage of iron in the diet
The body relies on the food you intake for many minerals, vitamins and nutrients, which are essential for bodily functions and good health. Iron is taken into the body through the diet, with good sources including:
- Dairy products.
- Fortified foods (with added iron), such as breakfast cereals.
If you do not consume sufficient food that contains iron, this can contribute to iron deficiency anaemia. People who eat very little, vegetarians and those who exclude certain foods from their diet are more likely to incur the condition.
People who have low fat diets, diets that are high in sugar and high fibre diets are more likely to incur iron deficiency anaemia. This is because low fat diets are frequently light in animal-based products, which tend to be rich in iron, while high fibre diets can cause problems with iron absorption, and diets that are high in sugar are frequently low in iron because very few sugary foods contain iron.
It is not advisable for children under the age of 12 months to have cow’s milk since it has low iron content.
Inability to absorb iron from food
Certain factors and health conditions can cause problems with iron absorption, which means that the body is unable to use iron, despite the fact that it is present in food taken into the body. Causes include:
- Conditions affecting the intestines, such as Crohn’s disease and celiac disease.
- Intestinal surgery.
- Taking prescription medication to reduce stomach acid.
- Decreased levels of folate (also known as folic acid), vitamin C and vitamin B12 in the diet.
Elevated need for iron
At certain times in life the body may require greater supplies of iron. If iron reserves are not sufficient during such times iron deficiency anaemia may develop. Times when the necessity for iron can increase include pregnancy, childbirth and times of rapid growth in teenagers and children. Pregnant women require double the intake of iron to cater for baby growth, blood loss during birth and an increased volume of blood in the body.
How does iron deficiency anaemia develop?
Iron is lost as a result of one of the three causes mentioned above. In most cases iron levels decrease gradually and the individual does not consume sufficient iron to keep levels stable. When iron levels are low the body begins to use iron reserves. Once the reserves have run out the red blood cells will contain a smaller amount of haemoglobin than usual, decreasing the amount of oxygen that can be transported around the body and the number of strong red blood cells produced in the bone marrow. When the proportion of red blood cells drops, this can result in iron deficiency anaemia.
Who is at danger from iron deficiency anaemia?
The most important risk factors are diets low in iron and blood loss. Most cases affect females, young children and patients who have intestinal conditions that cause bleeding.
Populations affected by iron deficiency anaemia
Women: women are much more commonly affected by iron deficiency anaemia than men. Around 1 in 5 females of an age appropriate for having children incur the condition and half of pregnant women suffer from the condition. Women who have heavy or long periods have a higher risk of incurring this health condition.
Children: young children aged between 6 months and 2 years require lots of iron because they are growing and developing so quickly. The iron stored in the womb during foetal development is used within the first 6 months, and it is important that young children take in plenty of iron through the food they eat, in addition to supplements. Babies with low birth weight and premature babies have a heightened danger of developing iron deficiency anaemia as their iron reserves are lower.
Children will also have a higher risk of iron deficiency anaemia in the following circumstances:
- Have a poor diet (anaemia is often more common in low income households).
- Drink cow’s milk before the age of 12 months.
- Breastfed after the age of 4 months without taking in additional iron supplements.
- Have lead in their blood.
Grown-ups with intestinal bleeding: adults who suffer from intestinal problems that cause bleeding have a higher risk of iron deficiency anaemia. Causes may include ulcers, colon cancer and taking medications that can result in bleeding, such as non-steroidal anti-inflammatory medication.
Other adults: other adults with a higher risk of iron deficiency anaemia encompass those with kidney problems that require dialysis, vegetarians and people with poor nutrition.
What are the signs of iron deficiency anaemia?
Indicators of iron deficiency anaemia vary according to the individual. Often, in mild cases, the individual may experience no signs at all. In severe cases, however, symptoms can be dangerous if left untreated. Most signs are similar to those associated with other forms of anaemia.
Common signs of iron anaemia:
The most common sign of all forms of anaemia is tiredness. This is caused by a low proportion of red blood cells, which results in a smaller quantity of oxygen being carried around the body. A shortage of oxygen can result in the following symptoms:
- Feeling light-headed.
- Feeling weak.
- Passing out.
As the heart is forced to function harder to pump blood around the body in cases of anaemia, additional symptoms can include:
- Shortness of breath.
- Chest pain.
- Heart murmur.
Anaemia causes a lack of haemoglobin in the red blood cells, symptoms of which include:
- Pale gums, nail beds and tongue.
Other symptoms of anaemia are:
- Cold feet and hands, caused by poor circulation.
- Brittle nails.
- Swollen, sore tongue and cracks on the side of the mouth.
- Increased susceptibility to infections.
- An enlarged spleen.
Signs of iron deficiency anaemia
Many symptoms of anaemia are common to different forms of the disease. Signs of iron deficiency anaemia are as follows:
- Unusual non-food cravings (such as paint, dirt and ice).
- Restless legs syndrome: this is a condition that causes pain in the legs, which can only be eased through movement. Restless legs syndrome often makes it difficult for people to sleep.
- Delayed development, poor appetite and increased irritability in young children.
Signs of iron deficiency anaemia are sometimes linked to the reason behind the emergence of the condition; blood loss, for example, is a major cause and commonly occurs during menstruation in women. Symptoms of internal bleeding include black stools or bright red blood in the stools.
What is the diagnosis process for iron deficiency anaemia?
Diagnosis is based on symptoms, a physical examination, medical history and diagnostic tests. The tests can also be used to assess the harshness of the condition and the cause. In many cases of mild anaemia there are no symptoms and the condition is often diagnosed during tests for other health conditions.
Primary care doctors (GPs) are usually able to treat and diagnose iron deficiency anaemia. However, in some cases specialists, including paediatricians, obstetricians, haematologists and internal medicine practitioners, may be consulted. If anaemia is caused by problems related to absorption of iron, a gastroenterologist may also be involved in the diagnostic and treatment process.
Family and medical history
If a patient has signs of iron deficiency anaemia, their doctor will ask them about their symptoms, family and medical history. This will help identify any underlying medical conditions that could be contributing to anaemia. Doctors will also ask if a woman is pregnant as this is a widespread cause of anaemia. Doctors may also enquire about diet and lifestyle habits.
A physical examination can enable doctors to reach a diagnosis of iron deficiency anaemia. During the examination a doctor will look out for the following signs and symptoms:
- Paleness in the skin, nail beds and gums.
- A rapid or uneven heartbeat.
- Enlargement of the spleen or liver.
- Rapid or irregular breathing.
- Bleeding: blood loss is the most widespread cause of iron deficiency anaemia.
Numerous tests will also be ordered to fix on the cause of iron deficiency anaemia and the harshness of the condition.
A range of tests can diagnose iron deficiency anaemia. The first test usually carried out is a complete blood count (CBC), also known as a full blood count. This test tells doctors a several important things, including:
- The level of haemoglobin: haemoglobin is a protein rich in iron, which is responsible for transporting oxygen around the body. The standard range of haemoglobin is between 11.1 and 15.0 g/dL; a result lower than this will indicate that the individual has anaemia.
- The haematocrit level: this measures the proportion of red blood cells in the blood. The normal range is between 32 and 43 percent, with a reading lower than this indicating anaemia.
The ranges listed above are rooted in the average population and ‘normal’ ranges may differ according to ethnicity. Your doctor will explain the test results to you before drawing up a treatment plan.
The complete blood count can also be used to assess:
- The proportion of red blood cells: if the test shows a low proportion of red blood cells, this indicates anaemia.
- The number of white cells (responsible for preventing infection).
- The number of platelets (involved in the clotting process).
- The dimension of the red blood cells: the average cell volume gives an indication of the average size of the red blood cells; if the red blood cells are smaller than normal, this may indicate anaemia.
If the complete blood count test indicates that a patient has anaemia, doctors will order further tests to establish the cause and harshness of the condition. One of the tests a doctor may order is a reticulocyte count (immature red blood cells). The results of the test will show if the rate at which red blood cells are being made by the bone marrow is sufficient.
Tests to assess iron levels in the body
Iron is required to make haemoglobin, a protein which gives red blood cells their colour and transports oxygen around the body. Many tests can calculate iron levels in the body, including:
- Serum iron: this examination establishes the sum of iron in the blood. The test result may be standard, even if there is a shortage of iron in the body, which is why additional tests are carried out.
- Serum ferritin: ferritin is a protein used to stock iron in the body. The test result gives doctors a guide as to how much iron the body has in reserve.
- Transferrin level (also known as total iron-binding capacity): transferrin is a protein which transports iron in the bloodstream. The test measures how much transferrin is not transporting iron. If there are high levels of transferrin not transporting iron, this indicates anaemia.
- Other blood tests: doctors may also order additional blood tests, including thyroid hormone and other hormone tests. A test to measure the levels of erythrocyte protoporphyrin, the chemical used to produce haemoglobin, may also be conducted.
Tests to diagnose gastrointestinal bleeding
Various tests can be carried out to check for gastrointestinal bleeding if a doctor suspects that anaemia is caused by internal bleeding. These include:
- Faecal occult blood test: this test checks for indicators of blood in the faeces. It can also detect tiny amounts of blood caused by bleeding in the intestines. It is typically the primary test to be carried out and if blood is discovered in the stool additional tests will be ordered; as follows:
- Colonoscopy: this test requires the passage of a thin, supple tube up the rectum and into the colon. The tube is fitted with a light source and camera to enable doctors to see detailed images of the inside of the organs.
- Upper GI endoscopy: this test involves using a thin, supple tube to see inside the upper part of the intestines and the stomach.
- Pelvic ultrasound: an ultrasound (high frequency sound waves) will be used to inspect the pelvis and uterus. It can detect the causes of vaginal bleeding including fibroids.
What treatment is there for iron deficiency anaemia?
Aims of treatment
The aims of treatment are to increase iron levels, reinstate regular proportions of red blood cells and haemoglobin and to treat the source of iron deficiency anaemia.
Types of treatment
The type of treatment recommended by doctors will depend on the individual case. Factors including the harshness of the condition and initial cause will impact the treatment pathway. In most cases treatment is designed to stop bleeding and re-establish regular levels of iron and red blood cells by altering diet and adding supplements. In severe cases more intensive treatment may be required.
Treatment to stop bleeding
This will depend on the cause of bleeding and its location. Bleeding must be stemmed in order to treat anaemia.
More iron in the diet
If you are diagnosed with iron deficiency anaemia it is likely that your doctor will advise you to adopt a diet with foods that are high in iron content. They will also advise the intake of foods rich in vitamin C and folate (folic acid). Beneficial sources of iron include:
- Red meat (especially liver and beef).
- Dairy products.
- Leafy green vegetables (including spinach, watercress and rocket).
- Nuts and pulses.
- Dried fruits.
- Fortified cereals and bread.
Foods high in vitamin C include:
- Fruits, especially citrus fruits, and fruit juices.
- Vegetables, including broccoli, cabbage and leafy greens.
In addition your doctor may also recommend iron supplements, which can usually restore iron levels to normal within 2 months if taken correctly. Iron supplements are available in tablet form for adults and drops for children. Vitamin C supplements may also be recommended. Iron supplements can be unsafe if taken in excess, so make sure that you follow dosage instructions carefully. Possible side-effects of Vitamin C and iron supplements include heartburn, mild stomach upset, constipation and dark stools.
Treatment for severe anaemia
If anaemia is severe it can be life-threatening if left untreated. Severe cases of anaemia require hospital treatment, which may involve iron injections and blood transfusions.
What can be done to prevent iron deficiency anaemia?
The best way to avert iron deficiency anaemia is to eat a healthy, balanced diet. Red meat has good iron content but there are plenty of other foods to consider:
- Fish and shellfish.
- Leafy green vegetables.
- Lentils, beans and pulses.
- Fortified cereals, bread and pasta (look out for labels saying ‘fortified with iron’).
- Dried fruits.
Fad dieting and eating very little often contribute to iron deficiency anaemia. It is advisable to avoid high sugar, low fat and high fibre diets, as these all tend to lack iron. Adults who have a good, balanced diet do not usually require iron supplements. However, such supplements may be advisable for people who have problems with iron absorption and vegetarians.
Preventing iron deficiency anaemia in young children
Regular testing is the most effective means of preventing young children from developing iron deficiency anaemia. Testing is especially important for premature babies, babies aged between 6 and 12 months and babies aged between 15 and 18 months. Babies take in iron better from breast milk; breastfed babies can absorb up to 50% of the iron in the milk, compared to just 12 percent in formula milk.
Doctors do not advise parents to give their babies cow’s milk until the age of 12 months. Cow’s milk has low iron content and drinking too much may prevent children from eating foods higher in iron.
As babies grow they need more iron, so it is advisable for those not breastfed to have formula milk that is fortified with iron. Fortified formula milk usually contains between 4 and 12 milligrams of iron. Once babies start eating solid foods they will benefit from iron fortified foods, including cereal.
Doctors can provide advice about children’s nutrition. If a child requires iron supplements, drops are available. Always make sure that you read the dosage instructions carefully and store medication away from the reach of children, as overdosing on iron can be potentially serious.
Preventing iron deficiency anaemia in females of childbearing age
Teenage girls and females at an age appropriate for having children are more likely to incur iron deficiency anaemia as a result of blood loss caused by menstruation. It is advisable for girls and women to be checked for anaemia on a regular basis (every 5 to 10 years). It is important that you visit your GP if you experience any symptoms linked to anaemia, including tiredness, weakness, paleness and feeling light-headed. Women with a high risk of anaemia, including those with a history of the condition, women with heavy periods and women with a low-iron diet, should have annual tests.
Preventing iron deficiency anaemia in pregnant women
Around half of pregnant females incur iron deficiency anaemia as a result of increased blood volume and growth of the unborn baby. Anaemia when pregnant can be very serious and result in premature birth.
Pregnant women require double the usual intake of iron. This can be achieved by increasing the sum of iron-rich foods in their diet and taking iron supplements. Pregnant women should also be checked for signs of anaemia and screened.
Doctors providing prenatal care may recommend iron supplements. It is important that pregnant women tell their doctor if they experience symptoms such as constipation and dark stools, as these are side-effects of supplements. Your doctor will also be able to offer nutritional advice about increasing your iron intake.
The prevention of anaemia in older people
Older people may have a heightened danger of incurring iron deficiency anaemia as a result of poor diet or underlying health conditions. Anaemia can cause tiredness, a lack of motivation and energy and it can also make indications of other health conditions worse. The prevention of anaemia can be promoted by eating foods rich in iron and taking iron supplements. Doctors can offer advice about diet and prescribe iron tablets.
Life with iron deficiency anaemia
Anaemia can be serious if left untreated. However, with appropriate treatment most people live fulfilling and healthy lives.
Ongoing medical needs
If you have been diagnosed and treated for anaemia, you will be advised to attend regular appointments with your doctor so that they can monitor your progress and check for signs of the condition returning. Your iron levels will be monitored closely and your doctor will discuss diet and treatment you may require.
While receiving treatment you may still feel tired and lethargic, as it will take time for your iron levels to return to normal. It is important that you inform your doctor if your symptoms become worse or you develop new symptoms.
Follow your doctor’s instructions carefully. Do not take iron supplements without talking to your doctor first, as this may cause an overload of iron in the body.
Pregnant women who have anaemia are usually tested again around 4 weeks after giving birth.
- Iron deficiency anaemia happens when there is insufficient iron in the body.
- Iron is important for the production of strong red blood cells and haemoglobin, a protein which is responsible for carrying oxygen around the body.
- There are three main reasons why an individual may have low levels of iron in their body; these include blood loss, a diet short in iron and problems which affect iron absorption. Iron deficiency can also come about when the body requires a higher level of iron, during pregnancy for example.
- 1 in 5 females of an age appropriate for having children suffer from the condition.
- Half of pregnant women incur the condition.
- Young children have a higher risk of iron deficiency anaemia.
- The most common signs include tiredness and feeling weak and lethargic.
- It can be treated by stopping blood loss, increasing iron intake through diet and taking supplements, in addition to treating conditions which cause problems with the absorption of iron.
- Eating a healthy, balanced diet is the most effective means of preventing iron deficiency anaemia; beneficial sources of iron include meat, poultry and fish, eggs, fortified cereals and bread, leafy green vegetables and dairy products.
- The condition is highly treatable and most people are able to live a very long and healthy life.