Do I have Iron Deficiency Anemia?
Iron is an essential mineral for athletes, particularly those focused on endurance events, following plant based diet and or are female. For many athletes, iron deficiency is not uncommon. Iron is well known for its role in oxygen transportation and delivery to help you power up hills, exercise at altitude, or crush an aerobic workout. In addition to its performance boosting capabilities, it also is essential at the mitochondrial level to produce energy and support your cognitive and immune function.
Those At The Greatest Risk of Iron Defiency
In comparison to the general population, athletes are at greater risk of being iron deficient. Up to ~35% of female athletes have iron deficiency versus ~5% in the general population. Regular exercise can increase your risk due to an increased inflammatory response in your body which decreases your ability to absorb iron for 3-6 hours after exercise. This inflammatory response increases your levels of the hormone hepcidin, a key regulator of iron. With increased levels of hepcidin, iron transport and absorption are reduced.
Female athletes, particularly those with heavy menstrual cycles.
Plant based athletes due to higher intakes of non-heme iron which has a lower absorption rate compared to heme iron found in animal products.
Athletes with low energy intakes that are not sufficient to meet energy demands of their body and training.
Adolescent athletes who have increased iron requirements during this period of life.
Endurance athletes (running, cycling, etc.) and weight regulated sports (rowing, gymnastics, jockeys, martial arts, etc.)
What is iron deficiency anemia?
Iron deficiency anemia occurs when the body does not have enough hemoglobin (Hb) to produce healthy red blood cells. The presence of microcytosis, or small red blood cells (RBCs), is a characteristic of anemia which is a result of decreased Hb production. The Hb molecule is made with iron and is a required component of your RBCs; within the Hb molecule, is the iron atoms that carry oxygen to your body’s tissues. In summary, without enough iron on board your body has a reduced capacity to produce healthy red blood cells which are essential for the transportation of oxygen to your muscles so you can exercise longer aerobically.
During the early stages of iron deficiency when your stores are reduced, yet not depleted, you can experience a slightly negative impact on your performance. As your stores become further depleted into iron deficient non-anemia (IDNA) and iron-deficient anemia (IDA) there will be a greater impact on your aerobic based athletic performance due to the decrease in the transport and deliverability of oxygen.
Table 1. Stages of Iron Deficiency
Symptoms of Iron Defiency
Symptoms can be mild or more acute, whether you are an athlete or coach, it is important to be aware of the symptoms to prevent poor exercise performance. I recommend regular testing at least once a year to prevent potential deficiencies or for early detection. Early detection allows you to quickly put interventions, such as diet and supplementation, into place to prevent any further decline towards IDA.
- Tiredness, fatigue or lack of energy
- Shortness of breath
- Poor recovery
- Decreased oxygen uptake
- Decreased endurance performance
- Decline in cognitive and physical performance
- Especially if training load is constant or during a recovery phase
What are the causes?
Iron deficiency anemia in young athletes can be multifactorial. This includes increased dietary needs, lack of dietary iron, periods of a growth spurt, vitamin D deficiency, and chronic illnesses such as celiac disease or Helicobacter pylori infection. In adolescents, a significant increase in blood volume in male and female athletes during puberty can be another cause of increased iron needs.
Other factors include the overuse of Non-steroidal anti-inflammatory drugs (NSAIDs: aspirin, ibuprofen, naproxen, Voltaren, Celebrex, etc.), footstrike hemolysis (common for runners), vegetarian diets, training at altitude, acute inflammation, heavy menstrual blood losses, gastrointestinal bleeding, chronic disease, intravascular hemolysis, or hematuria.
Diagnosing Iron Deficency Anemia
Iron deficiency is diagnosed with a blood test panel that includes serum ferritin, hemoglobin concentration and transferrin saturation. Ensure you work with an experienced sports dietitian (like Eleanor) or physician and have your labs completed with a reputable testing company. To improve the validity of your test follow these protocols:
- complete your blood draw in the morning
- ensure you are well hydrated
- complete the sample 12-24 hours after exercising preferably in a rested state
- eccentric exercise which can damage your muscles should not be completed 2-3 days before the test due to increases in inflammation
- we want to ensure the test results reflect your potential deficiency and not stress or inflammation in your body from a workout
- if you feel ill, wait to take the test until you are well again
- Ferritin: a blood protein that contains iron and helps us understand how much iron your body is storing
- Hematocrit: the percentage of your blood made up by RBCs. With anemia your RBCs will be smaller and paler than normal.
- Hemoglobin: 70% of the iron in your body is in the form of hemoglobin
- Transferrin: a protein that binds to iron and transports it throughout your blood to various body tissues
- Hepcidin (optional): elevated levels of this marker can be a sign that you are overreaching or over training.
- Plays a key role in iron regulation. If its elevated, you iron absorption and transportation will be low.
- This marker is impacted by exercise. Ensure you are 12-24 hours from your last workout when having your blood drawn for an accurate analysis.
If you think you might have iron deficiency anemia, I encourage you to book a complimentary call so we can assess your risk together and provide you with care options to help you take the next step with treatment. Heal from the inside out with accurate testing, nutrition and supplementation strategies.
For food sources and supplement recommendations for anemia, check out my next blog post Treating Iron Deficiency Anemia coming soon!
Karpinski, C., & Rosenbloom, C. (2017). Sports nutrition: A handbook for professionals. Academy of Nutrition and Dietetics.
Wonznik, P. (2023, April 10). The most important and up-to-date scientific evidence to answer your iron deficiency anemia questions.: Health conditions. Examine. https://examine.com/conditions/iron-deficiency-anemia/