Q How do I know if I’m iron deficient? How does it affect training? Jane Trench
A First of all, let’s clear up the common misconception that iron deficiency equals anaemia – this isn’t the case. Anaemia is a more severe form of iron deficiency, and can be caused by a lack of other vitamins or a symptom of other medical issues.
Iron deficiency without anaemia (IDWA) occurs when ferritin (a protein in the blood that contains iron levels) levels fall below 30μg/l. It’s possible to feel symptoms even with normal Hb (hemoglobin levels) and not meet the criteria for anaemia.
A simple blood test at your GP to check your ferritin levels will determine whether you’re deficient. From there you can discuss the results and treatment plan. They may still suggest iron supplementation if you aren’t anaemic, should your ferritin levels be below 30μg/l.
The symptoms of iron deficiency include fatigue, headaches, dizziness, brain fog, heavy periods, hair loss/thinning, restless leg syndrome, heart palpitations, shortness of breath and pale skin.
Female athletes are more susceptible due to blood loss during menstruation, with those who have heavy periods or short cycle lengths at the highest risk. Others at risk also include vegans, vegetarians, and those who restrict nutrient intake during phases of dieting.
Iron is a key component in hemoglobin and myoglobin, the molecules that carry oxygen in red blood cells to the muscles. Low iron levels can therefore result in reduced transportation of oxygen around the body and fatigue.
Iron is also responsible for energy production at a cellular level and is vital for cognitive and immune function. Athletes are at a greater risk of iron deficiency than the general population because the inflammatory response post-exercise can reduce the body’s ability to absorb it.
Of course, fatigue can be caused by many other factors, such as overtraining and under-recovery (poor nutrition, sleep, hydration), but athletes would be wise to get a blood test. If diagnosed with iron deficiency you may be offered supplements or sometimes an injection, or you may be advised to make dietary changes.
But not all iron is created equally, for example heme iron is found in animal and fish sources and is more bioavailable/ readily absorbed and utilised by the body.
Non-heme iron is found in plant sources – beans, pulses, wholegrains and dark leafy greens – and isn’t as easily absorbed, so larger amounts are required for the same benefit. Bread, cereal and pasta are useful as they’re often fortified with iron.
Vitamin C can help promote the absorption of iron within the body when consumed at the same time, so drinking a glass of orange juice with supplements/food is advised. Conversely, drinking caffeinated beverages can inhibit the absorption of iron, so having these with a meal should be avoided.