Feeling tired and run down? Athletes often attribute these feelings to overtraining, but the real culprit could be iron depletion. Low iron can cause you to feel unusually tired, impacts your ability to keep up in regular workouts or even causes performance plateaus. Low iron is all too often overlooked when trying to identify the cause of these common but serious issues for athletes.
Iron is an essential mineral that must be consumed through the diet. Iron helps the body use and bring oxygen to working muscles. When iron levels become too low, hemoglobin levels can become abnormally low. Hemoglobin is a protein in our red blood cells that carries oxygen. When hemoglobin drops below a certain point due to a lack of iron in the diet, it is classified as iron deficiency anemia. Iron deficiency anemia can cause fatigue, low motivation and an increased risk of illness. However, endurance athletes can have hemoglobin levels that are in the normal range but their ferritin levels are low. Ferritin is the storage form of iron. When ferritin levels are low and hemoglobin is within the proper range, you can still suffer negative consequences in athletic performance. The threshold for normal ferritin in athletes is different than the sedentary population. Because of this difference between the general and athletic population, ferritin levels that are too low for athletes are often overlooked as normal. The threshold for normal ferritin for athletes is often pegged at 30 micrograms/L, but there is a lack of research on where problems can start to occur.
Athletes are at an increased risk of having an iron deficiency that can lead to low levels of ferritin or hemoglobin. For instance, some athletes fail to get enough iron in their diet through foods. Many things interfere with iron absorption such as calcium, tea and coffee. Blood losses, such as monthly menstruation, can also increase the risk of low iron levels, as can hard training since red blood cells can be destroyed during exercising when our feet hit the ground. Even sleep deprivation can cause an increased risk of iron deficiency since it increases the level of a liver hormone that decreases iron absorption.
The amount of iron you need in your diet depends on your age and gender. Women need more iron than men or menopausal women because of blood losses during their menstrual cycle. Iron in foods can be classified as either heme or non-heme. Animal food sources of iron, such as red meat, are heme iron and more easily absorbed than non-heme iron. On the other hand, plant sources of iron, such as beans and lentils, are non-heme iron and not as well absorbed. The poorer absorption of non-heme iron is why vegetarians need almost twice as much iron as a non-vegetarian.
If you are worried about your iron intake, some easy steps you can take to increase your intake include:
- Aim to eat lean cuts of beef, pork, lamb and the dark meat of chicken or turkey 3-4 times per week
- Don’t drink coffee and tea for the hour before and after meals as they reduce iron absorption
- Try cooking with a cast iron skillet to increase the iron content of the food
Non-heme iron absorption can be enhanced by vitamin C. If you’re a vegetarian, consume plant sources of iron (from the list below) with foods containing vitamin C such as citrus fruits, cantaloupe, strawberries, broccoli, tomatoes and peppers.
Some of the top plant sources of iron include:
- Fortified cereals and breads
- Tofu and other soy products
- Beans and lentils
- Roasted pumpkin or squash seeds
- Blackstrap molasses
If you haven’t tried my recipe for sweet-potato & beet hummus click this link, it contains chickpeas, which is a good plant source of iron. The lemon juice and sweet potatoes in the hummus contribute vitamin C to help with the absorption of the iron in the chickpeas. You could also pair the hummus with cut up red peppers, broccoli and cauliflower for additional vitamin C!
Because it takes 3 months to bring hemoglobin levels to a normal level, you want to catch low iron levels as early as possible. As an athlete, it’s a good idea to get your blood checked routinely to ensure you have normal levels of hemoglobin and ferritin. If you do get your blood checked and your hemoglobin levels or ferritin levels are low, you will need to take an iron supplement to bring your levels back to normal. However, you should not take your iron supplement in the period immediately after strenuous exercise because there is a decreased absorption of iron during this period. You should never take an iron supplement without first getting your blood checked since an iron overload can be toxic. Based on your DNA, some people are more at risk for an iron overload than others. On the other hand, some people are also more susceptible to low iron status than others. This can be identified through genetic DNA testing.
I hope that this was an informative blog. Again, I really encourage all athletes to get their blood checked on a regular basis to stop problems from happening before performance is severely affected. If anyone has any questions, feel free to contact me.
I will be holding a free group talk at the Wayne Gretzky Centre at the end of February. The topic: “Runner’s Trots: How to Prevent the Runs While on the Run.” To keep up to date on this and other exciting events by sure to like my facebook page: Megan Kuikman Registered Dietitian.