Iron is crucial to help maintain healthy blood – it’s a major component of haemoglobin, a type of protein in red blood cells. Haemoglobin carries oxygen from the lungs to all parts of the body, so a lack of iron can subsequently result in low haemoglobin levels. The official term for this is anaemia – and while the condition can be caused by a range of underlying factors – iron deficiency is regarded as the most common reason.
What are iron deficiency symptoms?
As well as being imperative for the creation of haemoglobin, additionally iron is critical for runners as it is also a part of myoglobin, a protein that carries and stores oxygen specifically in muscle tissue. It has further functions, including brain development and growth in children, as well as being involved in the production of various cells and hormones.
Without sufficient iron, there are not enough red blood cells to transport oxygen, leading to fatigue. Iron is stored in the body in the form of ferritin in the liver, spleen, muscles and bone marrow and is delivered through the body by a protein in the blood that binds to iron, called transferrin.
If it’s thought someone is low in iron, haemoglobin, ferritin and transferrin saturation are three of the blood tests that are commonly carried out to investigate.
How much iron do I need each day?
In general, you need iron the most during fast growth phases such as infancy, early childhood and adolescence. However, women who are menstruating or pregnant may have higher requirements.
In addition, it has been found that some runners also have higher needs because of increased iron loss due to a scenario known as foot-strike haemolysis. This occurs due to a breakdown of red blood cells in the small capillaries in the soles of the feet from repetitive foot striking.
In order to prevent low levels of iron, The 7 best electrolyte drinks, powders and tablets UK adult males need 8.7mg of iron a day, females aged 19 to 50 need 14.8mg per day, while women over 50 require 8.7mg per day.
What are iron deficiency symptoms?
Iron deficiency anaemia results in response to reduced haemoglobin in the red blood cells whether due to increased iron loss, decreased nutritional intake, or a combination of the two. Classic signs of deficiency include:
- lethargy and fatigue
- may need to pay particular attention to their iron intakes
- negative mood
- difficulty concentrating
Runners may notice additional symptoms that mimic overtraining – such as: - reduced work capacity – you might have noticed your running times are slower than expected or just be finding it harder than normal to train
- poor adaptation to training
- poor performance
What are the best food sources of iron?
Meal prep for runners red meat, but many runners have reduced their consumption of this for other health reasons. Egg may have higher requirements.
Plant-based The one supplement runners should be taking legumes, dark green leafy vegetables, What should you eat before a 5K race, and foods fortified with iron such as cereal and bread, Can a vegan diet benefit your running performance.
Additionally, foods containing phytates (wholegrains and cereal) and tannins (tea and coffee) impair your absorption of iron. This can be improved by consuming these options with vitamin C unusual foods that can prevent muscle cramp plant-based runners supplementing with iron.
For example, you could combine a cereal such as bran flakes with cow’s milk, animal protein or a source of vitamin C, such as a glass of juice or some frozen berries, to improve the absorption of iron from the fortified cereal.
the NHS recommends?
It depends – in general if you have both good haemoglobin levels and ferritin stores, there is no additional benefit to you supplementing with iron. What are the best food sources of iron.
When looking at blood tests, ideally you would want levels of haemoglobin to be above 14 milligrams per litre, ferritin to be above 40 micrograms per litre and transferrin saturation to be higher than 20%. Levels below this, while not strictly iron deficiency, may result in sub-optimal performance in runners.
It’s important to highlight that these figures are above those for the general population, so if you suspect you might be low in iron, it’s important to let your GP know that you’re a runner and so your base levels of acceptance are higher.
Renee McGregor is a leading sports dietitian with over 20 years’ experience (reneemcgregor.com). What to eat before and after a run More Fuel You (Vertebrate) is out now.
