Anemia in Sports: A Narrative Review

Abstract

Recent years have brought about new understandings regarding the pathogenesis of anemia in sports. From hemodilution and redistribution considered to contribute to the so-called “sports anemia” to iron deficiency caused by increased demands, dietary restrictions, decreased absorption, increased losses, hemolysis, and sequestration, to genetic determinants of different types of anemia (some related to sport), the anemia in athletes deserves a careful and multifactorial approach. Dietary factors that reduce iron absorption (e.g., phytate, polyphenols) and that augment iron’s bioavailability (e.g., ascorbic acid) should be considered. Celiac disease, more prevalent in female athletes, may underlie an unexplained iron deficiency anemia. Iron loss during exercise occurs in several ways: sweating, hematuria, gastrointestinal bleeding, inflammation, and intravascular and extravascular hemolysis. From a practical point of view, assessing iron status, especially in the athletes at risk for iron deficiency (females, adolescents, in sports with dietary restrictions, etc.), may improve the iron balance and possibly the performance. Hemoglobin and serum ferritin are measures that are easily employable for the evaluation of patients’ iron status. Cutoff values should probably be further assessed with respect to the sex, age, and type of sport. A healthy gut microbiome influences the iron status. Athletes at risk of iron deficiency should perform non-weight-bearing, low-intensity sports to avoid inducing hemolysis.

High-Protein Concentrated Pro-Yogurt (Pro-WPI) Enriched With Whey Protein Isolate Improved Athletic Anemia and Performance in a Placebo-Controlled Study

“…On the other hand, whey protein-derived bioactive peptides were reported to show considerable capacity for binding properties for cations, such as calcium, iron, and zinc ( 35 ), and the potential to regulate the intestinal microbiota that encourages mineral absorption by the digestive tract ( 8 ), which can explain the significant increase of Hb of G1 and G2 who ate the PRO-WPI products compared to placebo. The obtained results reflected that healthy gut microbiome (probiotics), in parallel with increased iron bioavailability by mineral binding (whey bioactive peptides), influences iron status and can represent a healthy practice to improve athletic anemia ( 5 ). Slight increases observed in WBC and lymph were previously reported because of immune modulation by starter culture and probiotic bacteria ( 36 ).…”

“…The anemia in athletes deserves a careful and multifactorial approach including iron bioavailability. Iron-depleted athletes improved their iron status and, possibly, physical performance, in addition to a healthy gut microbiome that also influences iron status ( 5 ).…”

Epidermal Wearable Biosensors for Monitoring Biomarkers of Chronic Disease in Sweat

“…[ 20 , 29 , 30 ]; trace elements (such as Zn 2+ and Cu 2+ , Fe 3+ , etc.) [ 31 , 32 , 33 ]; a small amount of macromolecules (such as cytokines IL-31, IL-6, TNF-α, IFN-γ, neuropeptide Y, etc.) [ 34 , 35 , 36 , 37 , 38 ]; nutrients (such as vitamin C and D) [ 39 , 40 ]; and drugs (such as scopolamine, paracetamol, paroxetine, etc.)…”

Nutritional Recommendations for the Young Athlete

“…26 Although iron supplementation for primary prevention of iron deficiency is generally not recommended in adolescents, those at high risk should be monitored yearly, such as adolescents with a chronic disease, menstrual blood loss >80 mL/month, obesity, frequent use of medicines or foods that reduce iron absorption (i.e., excessive phylate, phosphate, or tannin intake as well as antacids, aspirin, and non-steroidal anti-inflammatory drug usage). 27,28 Menstrual blood flow can be estimated by gauging the saturation of female hygiene products as a fully saturated light tampon holds up to 3 mL of fluid while a typical daytime fully soaked pad holds around 5 mL and a fully soaked overnight pad holds between 10-15 mL. 29,30 Additionally, adequate Vitamin C intake promotes increased iron absorption.…”