Iron, the Least Talked About Mineral in Sport Nutrition

by Alister Gardner , 4-6 minute read

Iron is a common nutrient deficiency

In sports, we hear a lot about protein, carbohydrates, hydration and electrolytes, all of which play a critical role in the day to day of an active, healthy lifestyle. Iron (the same iron as in your iron skillet) is also an essential part of our nutrition needs, especially for endurance athletes. Iron is used by red blood cells to transport oxygen from our lungs to the mitochondria (the power stations of our cells) in our heart and muscles. It is considered by many as the most critical mineral associated with sports performance and is also the most common nutrient deficiency worldwide.


What foods can I get iron from?

There are two types of iron available from food; heme iron, which comes only from animal sources and non-heme iron which is in both plants and animal sources. The iron in meat is made up of around 40% heme and 60% non-heme iron. Eggs and dairy only have non-heme iron. The absorption of heme iron is not greatly affected by other foods we eat, whereas non-heme iron can be affected in both a positive and negative way.


How Low Iron Levels Evolve

Whereas a sports drink or protein bar will have an impact on our performance and recovery that same day, changes in our iron levels happen gradually and the effects of low iron levels are seen over months and years. Our bodies are good at recycling iron but athletes still need a healthy intake of iron to be sure to avoid low levels. Low iron levels start with a drop in our body’s iron reserves which does not affect performance, but as that reserve becomes depleted it inhibits our production of red blood cells which in turn affects oxygen transport, reducing our VO2 max and our ability to perform. Less oxygen to the muscles means a lower aerobic performance!

Symptoms of low iron levels

The main symptoms of low iron levels are a slight shortness of breath and fatigue. This is a bit of a dilemma as both these symptoms are common sensations associated with endurance sports. In severe conditions a feeling of dizziness can arrive during longer workouts. If the symptoms appear for no apparent reason, especially for seasoned athletes then it is important to see your doctor about a blood test. It is not something to be self-diagnosed, a blood test is the definitive method of knowing your iron levels.


What causes iron loss in athletes?

We regularly lose a little iron each time we sweat, which means people who train very regularly (as often as twice a day, 5 days a week) are prone to lose more than the average person
In women, menstruation losses and often lower dietary intake means female athletes are often at a higher risk of iron deficiency.
For runners, the impact of running increases the damage to red blood cells and can contribute to low iron levels
Dietary factors include drinking caffeine with meals which inhibits the absorption of iron. Also, diets low in iron rich foods will mean not enough supplementation.
There are also genetic factors which can play a big part in an individual’s iron absorption as well any illness or inflammation in the digestive system, for example Celiac disease.


Preventing Iron deficiency

For the majority of people, it is important to include iron rich foods in your diet. Dark leafy greens and beans are a great source. As well as iron fortified cereals, breads and pastas. For athletes a daily supplement is recommended too.
Vitamin C helps with non-heme iron absorption so combining iron rich foods with food with plenty of sources of vitamin C is good (a glass of orange juice with breakfast for example).
Avoid drinking coffee and tea with your meals, allow 45-60 minutes either before or after you eat. It is often recommended to athletes who train regularly to take an iron supplement, a good time is just before going to bed.

Why do we to fortify E-Beet XACT ENERGY with Iron?

The issue of low iron levels was raised by several of our female athletes and it didn’t take us long to realize that adding iron to a XACT ENERGY fruit bar made perfect sense. We were already supplementing energy so why not iron at the same time? Et voilà! XACT ENERGY E-Beet’s benefits to endurance athletes was taken to the next level! For many of our athletes, the XACT ENERGY E-Beet is considered as their energy bar for training, eaten regularly throughout the week while on long runs and rides, and so as months of training go by they are reassured that they’re getting iron from an additional source. Often they may switch to the XACT ENERGY blackcurrant for races in order to leverage the benefits of caffeine during the times where maximum performance is most needed. XACT ENERGY E-Beet has 40% of the RDA (recommended daily allowance) of iron. So a regularly using E-Beet can be a helpful contribution of iron to both endurance athletes and folks leading active lifestyles.

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Alister is an elite runner and has a diploma in sport nutrition. He is co-owner at Course et Cie, an independent run store in Granby, Québec as well as co-owner of XACT nutrition. 
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