If exercise is meant to make you healthier, why are some athletes at higher risk of becoming anaemic? In this article, we talk you through the causes of anaemia in the athlete, and how to make sure this problem doesn’t affect you or your kids in your quest to good health!
Anaemia refers to abnormally low red blood cells or haemoglobin in the body. Haemoglobin (which contains iron) is the compound in the blood cells that carries oxygen from the lungs to the muscles and organs in the body. Since we all need oxygen to survive, and the muscles need oxygen to work effectively, having a normal haemoglobin/iron level is very important for an athlete wanting to perform well!
Iron problems can have a big impact on performance. Reduced oxygen carrying capacity will decrease your maximal aerobic capacity (VO2 max), lower endurance, increase fatigue and compromise your immune system. Athletes may complain of less power, getting tired easily, loss of appetite, frequent injury and may have recurring illness like colds.
Athletes at a higher risk of developing iron deficiency anaemia include female athletes, endurance runners and swimmers. An athlete may develop iron deficiency either due to inadequate dietary intake, inadequate absorption or increased iron loss.
1. Inadequate intake
The best source of iron is animal products, such as lean meat, poultry, fish or liver. Iron is also found in plant products, but this iron does not absorb as well as that in animal products. Groups at risk of inadequate intake are vegetarians and any athlete who diets or restricts their calorie intake in order to maintain a slim physique (adolescents, gymnasts, ballet dancers).
2. Inadequate absorption
Iron absorption is decreased significantly if taken in with foods containing caffeine, calcium or zinc. So don’t wash down your meal with coffee or tea but choose orange juice instead! Fruit enhances iron absorption (citrus in particular because of the vitamin C).
3. Increased Iron loss
In females, the biggest loss occurs during menstruation. This is why the recommended daily intake of iron is higher for females (15mg/day) than men (10mg/day). Usually a much higher amount of iron is contained in iron supplements.
Blood loss from the gut and in the urine has been widely documented in endurance runners. Bleeding in the gut and bladder is said to be caused by decreased blood flow to these organs (ischaemia) and by mechanical trauma when running for extended durations, especially runners with a high stamping gait and those who run on hard surfaces. The mechanical trauma would result from organs bumping against each other during the run. There is not much that can be done to prevent this kind of loss, so runners just need to be aware of their bodies increased demand for iron and be sure to take in enough iron with meals. An important note is that blood loss from the gut can also be made worse by using anti-inflammatory drugs, so parents- be careful that you aren’t giving your children anti-inflammatories unnecessarily or for extended durations.
Blood can also be lost in sweat and by a process called haemolysis (swimmers, rowers and runners). Haemolysis is the breakdown of blood cells. In athletes it is believed to be caused by an increased body temperature and altered flow in the blood during vigorous sport.
No conversation about anaemia in the athlete is complete without mention of the phenomenon known as Dilutional or Pseudo Anaemia. One of the ways in which the body adapts to endurance training is by increasing blood volume. Because the red cell mass remains unchanged, there is a relative decreased concentration of haemoglobin: it appears low because of the increased amount of surrounding fluid. This is not a true anaemia as the actual red cell mass and haemoglobin is usually normal. So, to make a diagnosis of true anaemia, doctors therefore also measure additional compounds such as Ferritin and Haematocrit which are also decreased in true anaemia. Pseudo-anaemia does not affect oxygen carrying capacity of the blood.
In summary, if you are aware of the causes of iron deficiency, you can start taking steps to prevent it.
Make sure you:
- Eat foods rich in iron,
- Increase delivery of iron to your body by eating these foods with Vitamin C,
- Avoid eating meals with food or drinks containing caffeine
- Be careful not to take anti-inflammatories unnecessarily or for prolonged duration unless advised by a doctor.
Eat well, train well, be well!
References available on request.
Yours in Health and Exercise!