From the Guidelines
Anemia is defined as a decreased red blood cell mass or hemoglobin concentration, with the World Health Organization defining it based on hemoglobin concentrations, specifically for women ≥ 15 years old, as mild anemia with a hemoglobin 11.0–11.9 ng dL −1, moderate anemia with a hemoglobin 8.0–10.9 ng dL −1, and severe anemia with a hemoglobin < 8.0 ng dL −1 1.
Key Points
- Anemia and iron deficiency are not synonymous, as it is possible for an individual to be iron deficient but not anemic, a condition known as “iron deficiency” or “iron deficiency without anemia” 1.
- The diagnosis of anemia involves a full iron panel, including a complete blood count with reticulocyte count, ferritin, serum iron, transferrin, transferrin saturation, and total iron binding capacity, as ferritin alone can be misleading due to its role as an acute-phase reactant 1.
- Certain populations, such as female athletes with restrictive diets, high amounts of repetitive ground strikes, endurance training, or heavy menstrual bleeding, are at a higher risk for iron deficiency and anemia 1.
- Treatment and prevention strategies include optimizing dietary iron intake, with iron from meat (heme iron) being better absorbed than plant-based iron (non-heme iron), and considering supplementation for individuals at high risk or with diagnosed iron deficiency or anemia 1.
Considerations
- The current USDA recommended daily allowance for iron may not be sufficient for athletes with risk factors, suggesting the need for personalized nutrition plans 1.
- Athletes should consult a sports dietitian to optimize their daily nutrition plans for iron intake, especially if they have restrictive diets that make adequate consumption of iron difficult 1.
From the Research
Definition of Anemias
- Anemia is a condition characterized by low hemoglobin levels, which can be caused by various factors, including iron deficiency 2.
- Iron-deficiency anemia is defined as low hemoglobin due to low iron stores, affecting approximately 1.2 billion people worldwide, including 10 million in the US 2.
- Absolute iron deficiency, which can progress to iron-deficiency anemia, is defined as low iron stores with or without anemia, affecting approximately 2 billion people worldwide and 14% of adults in the US 2.
Types of Anemias
- Iron-deficiency anemia: caused by low iron stores, often due to bleeding, impaired iron absorption, inadequate dietary iron intake, or pregnancy 2.
- Nonanemic iron deficiency: a condition where individuals have low iron stores but do not yet have anemia, which can still cause symptoms such as fatigue, irritability, and depression 2.
Diagnosis and Screening
- Testing for iron deficiency is indicated for patients with anemia and/or symptoms of iron deficiency, such as fatigue, pica, or restless legs syndrome 2.
- Diagnosis is typically made by measuring low serum ferritin (typically <30 ng/mL) in individuals without inflammatory conditions or by transferrin saturation (iron/total iron binding capacity × 100) less than 20% 2.