Spending significant time at higher altitudes increases the body's demand for iron, primarily because iron is a critical component in the production of red blood cells. Prolonged exposure to altitude stimulates the production of erythropoietin, a hormone that promotes the creation of red blood cells to improve oxygen transport and compensate for lower oxygen levels in the environment. Without adequate iron, this process can be impaired, leading to neutral or negative physiological adaptations to altitude.

Key points to consider:
1. Increased Iron Demand At altitude, the body ramps up the production of red blood cells, thus increasing the requirement for iron. Iron is an essential element for hemoglobin synthesis, which is necessary for oxygen transport in the blood.

2. Iron Deficiency Risk:

Without sufficient iron intake, the body may struggle to produce the additional red blood cells needed at altitude. This can lead to iron deficiency anemia, characterised by fatigue, decreased performance, and impaired recovery.

3. Negative Adaptations: 

In the absence of adequate iron, athletes might experience neutral or even detrimental effects from altitude exposure. Instead of gaining the expected benefits, such as increased Hbmass and improved oxygen transport, they could face reduced physical performance due to insufficient iron stores.

Conclusion:

Ensuring adequate iron intake is crucial for athletes and individuals spending significant time at altitude. Iron supplementation can support the increased iron demands, promoting effective erythropoiesis and optimizing physiological adaptations to altitude. Without adequate iron, the potential benefits of altitude exposure might be compromised, adversely affecting overall performance and health.The study demonstrates that a period of two to four weeks of exposure to low to moderate altitude (1,350–3,000 meters) can increase hemoglobin mass (Hbmass) in well-trained athletes who receive iron supplementation. Key findings include:

Key points to the reference study. 

1. Altitude Exposure and Hbmass: Training or living at altitudes between 1,350 and 3,000 meters boosts Hbmass, enhancing the blood's oxygen-carrying capacity, which is advantageous for athletic performance.

2. Iron Supplementation Efficacy: Athletes who received daily oral iron supplements (105 mg or 210 mg) exhibited improved erythroid iron incorporation. These athletes also had higher serum ferritin levels compared to non-supplemented athletes, indicating better iron status.

3. Iron Stores and Performance: The supplementation not only supports Hbmass production during moderate altitude exposure but also helps replenish iron stores in athletes who might be iron deficient, contributing to better overall athletic health and performance.

Conclusion: Oral iron supplementation is likely beneficial for athletes exposed to moderate altitudes by enhancing Hbmass production and maintaining adequate iron stores. This practice might be particularly advantageous for those who are iron deficient, ensuring they achieve optimal performance benefits from altitude training.
In summary, integrating oral iron supplementation into the training regimen of athletes exposed to moderate altitudes appears to be a strategic approach to maximise physiological adaptations and maintain iron balance, ultimately supporting enhanced athletic performance.

Study reference

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4532405/