Alexandra Cook explains how to look for signs of iron deficiency and how to combat it
You train hard, sleep well and look after yourself, yet you still feel exhausted. Does this sound familiar? Fatigue comes hand in hand with training and for most a good snooze alongside a day’s rest should put things right. Constant tiredness, shortness of breath and reduced performance can be symptoms of many things, but one that must be considered is iron deficiency. It is not uncommon in endurance athletes, especially females. The healthiest athlete can be iron-deficient, so do not worry – if identified early, you will be on top form in no time.
Iron is an essential mineral, which is important to endurance athletes because of its roles in energy metabolism, immune function and providing oxygen to the working muscles. Very important for runners, iron makes haemoglobin, which has the important job of carrying oxygen to the working muscles. Any iron that is not used is stored in the liver in the form of ferritin.
The problems lie in that the body does not produce its own iron, so there is a firm reliance on a good, iron-rich diet to fulfil these roles. Realistically, achieving the perfect diet can be tricky, so what happens if iron intake is low and the levels drop? Well, iron-depletion is continuous and the sooner it is recognised, the easier it is to rectify. If identified early, it will develop from iron depletion (non-anaemic) into iron deficiency anaemia. Advances occur when iron stores have become so low that production of haemoglobin and red blood cells are reduced, causing the body to work more slowly, resulting in symptoms (see below) and a reduction in performance.
Symptoms of iron deficiency
» Lasting fatigue
» Shortness of breath
» Poor performance
» Low motivation
» Heart palpitations
» Pale skin
If iron deficiency is suspected, don’t self-diagnose and treat. A blood test from your GP is needed to rule out anything else and to diagnose levels of iron depletion. Monitoring over time may be needed as false readings can occur due to sports anaemia where training causes a rise in the plasma volume in the blood, resulting in a dilution of haemoglobin and false reading of iron levels. This does not require treatment and is unlikely to affect performance.
Various factors suggest why a runner may develop iron deficiency. Loss of iron through sweat has been postulated alongside iron loss through urine or gastro-intestinal bleeding that occurs in a small percentage of runners. Although plausible, evidence is not conclusive.
There is also a phenomenon called “foot strike haemolysis”, which is a destruction of red blood cells as a result of constant foot pounding on the ground. The lossof cells in this process, however, is not thought significant enough to show up in a blood test. In reality, the most likely cause is not meeting requirements through diet. Men need only 8mg per day, but menstruating, non-pregnant women need 18mgs per day. These increased needs for women are reflected in the fact that iron deficiency is seen more commonly in women.
If diagnosed with iron deficiency anaemia, supplementation, as guided by your healthcare professional is essential to bring levels back up. It can take weeks or months to get a spring back in your step, so be patient. Levels should be re-checked and, when back to normal, supplementation can cease. An increase in iron-rich foods is also needed to maintain iron store levels, although absorption is dependent on the form of iron eaten (whether animal or plant), meal composition and iron levels of the individual. Following a healthy balanced diet containing a variety of high iron foods will help you achieve adequate iron status.
Top tips to increase iron intake
» Iron in animal products such as red meat and liver is better absorbed than iron in plant-based foods and cereals
» Choose lean red meat 2-3 times a week (80-100g)
» Liver, fish, chicken can make up the remaining days
» Ensure breakfast cereals have added iron
» Combine animal and vegetarian sources of iron
» For vegetarians, eat plenty of beans, dark green leafy vegetables and eggs
» Snack on dried fruit such as apricots, prunes, raisins and nuts
» Add to meals vitamin C-rich foods such as fruit, juice, broccoli, and peppers as these enhance the absorption of iron
» Avoid drinking tea or coffee with meals, as the tannins inhibit iron absorption – drink between meals only
Iron deficiency can be hugely detrimental to performance, but awareness is key. If in doubt seek advice from a health care professional or team medic, if only to rule out any other underlying problems.
» Alexandra Cook BSc P.g. Dip RD is a sports dietitian and a club runner with Thames Hare and Hounds. DIET 360 is a private dietetic and nutrition consultancy covering Lincolnshire, Rutland and Leicestershire (diet360.co.uk)