1. The Importance of Iron Supplementation for Female Athletes
Marissa Uhlhorn
Aramark Dietetic intern
4/20/17

2. Iron’s Role in the Body
Essential micronutrient involved in blood production
70% of the body’s iron is found in red blood cells (hemoglobin) and muscle cells (myoglobin)
 Hemoglobin: Transfers oxygen in blood from the lungs to the tissues
Myoglobin: Accepts, stores, transports, and releases oxygen in muscle
6% of body’s iron is a component of proteins essential for respiration and energy metabolism
25% is stored as ferritin (protein that binds to iron)- found in liver, spleen, muscle, bone marrow

3. Dietary Sources of Iron
To maintain sufficient iron levels, recommended daily allowance (RDA) for healthy premenopausal women is 18 mg/ day
LENTILS
1 cup = 6.59 mg of iron
SPINACH
1 cup = 6.43 mg of iron
BEEF
3 ounces = 5.24 mg of iron
Dark chocolate
1 square = 5 mg of iron
cashews
1 ounce= 1.7 mg of iron
Kidney beans
1 cup = 5.2 mg of iron
OYSTERS
3 ounces= 5.91 mg of iron
TOMATOES
1 cup = 3.39 mg of iron
CHICKPEAS
1 cup = 4.74 mg of iron
Pumpkin seeds
1 ounce = 4 mg of iron
Vitamin C enhances the bioavailability of nonheme iron
Nonheme- Non meat sources
Meat sources- heme + nonheme

4. Iron and Hemoglobin Levels
Normal Hemoglobin Levels:
Men: g/dL
Women: g/dL
(ND uses g/dL)
Normal Ferritin Levels (sFer):
Men: ng/mL
Women: ng/mL
ND uses ng/mL
Hepcidin: Circulating Hormone-negative regulator of iron status
Upregulated by inflammation
Increased levels linked to decreased iron levels and prevention of iron absorption
Decreased levels linked to increased iron levels and facilitation of iron absorption

5. Causes of Iron deficiency in Athletes
Hemolysis (physical sheering of red blood cells –foot strike & impact)
Poor dietary intake
Increased iron losses: Intestinal bleeding, hematuria (blood lost in urine), sweat
Altered intestinal iron absorption caused by effects of inflammation due to training.
Menstrual losses (in females)

6. iron deficiency and Anemia
Functional or Subclinical Iron Deficiency (ID)
When iron stores have become depleted but Hgb has not yet declined to an anemic level:
Tissue oxidative capacity is affected , endurance performance is impaired
Hgb synthesis and O2 transport are not affected
Severe Iron Deficiency (ID)
Hgb synthesis compromised- depleted iron stores – Iron Deficiency Anemia (IDA)
Reduced O2 transports (V02 Max), Reduced tissue oxidative capacity (endurance capacity, energetic efficiency)
SUMMARY:
 Limits the body’s capacity to carry and deliver oxygen
Decreasing maximal oxygen uptake (VO2max) Decreased performance levels
Associated with higher blood lactate concentrations during exercise
Increased fatigue
Immune abnormalities

7. Iron Overload
Definition: Increased total body Fe stores with or without organ dysfunction
Primary iron overload: defect in regulation of iron balance
Secondary iron overload: Excess iron intake (dietary or supplementation)
Long term effects: organ and cellular damage due to oxidative stress & formation of free radicals
Tolerable Upper Level: 45 mg/day elemental Iron with already normal levels

8. Current Practices at Notre Dame
Female athletes are screened 2x/year for iron deficiency
Serum Ferritin levels checked- most common index of body Fe stores
ND’s Normal Ferritin Range: ng/mL
ND’s Normal Hemoglobin Range: g/dL
If Ferritin levels are below 40 ng/mL:
One 65 mg supplement of Nature Made Iron Tablet given daily Mon-Sun (equivalent to 325 mg Ferrous Sulfate/day)
If Ferritin levels below 20 ng/mL:
Two 65 mg supplements of Nature Made Iron Tablets given daily Mon-Fri (equivalent to 740 mg Ferrous Sulfate/day)
OR 1-2 Vitron C (elemental iron + Vitamin C) given daily Mon-Sun (1 tablet contains 65 mg elemental Fe)
If stomach issues- slow releasing iron supplement can be given (50mg) OR Easy Iron Chewables (20 mg)

9. Current Evidence-Based Recommendations
Iron Supplementation for:
Those with IDA (Hgb <12 g/dL, sFer <12 ng/L)
Athletes with consistent suboptimal dietary intake (e.g., vegetarians/vegans, weight-control sports, endurance runners, etc.).
Individuals with normal Fe status (Hgb >12 to 13 g/dL, sFer >30 ng/L) likely will not benefit from supplementation
If Iron deficient (decreased Ferritin levels):
Supplement with 100 mg Ferrous Sulfate daily (20 mg elemental iron)
Monitor iron status throughout training season
Monitor compliance to supplementation and encourage dietary intake
Absorption:
Most efficient/absorbable when consumed daily with source of Vitamin C (citrus juice)
Less absorbable when consumed with polyphenolic compounds such as coffee or tea
Less absorbable when consumed with calcium rich foods or calcium supplements (including Tums)

10. Current Evidence-Based Recommendations Summary
Low to moderate iron supplementation (100mg/d) among female athletes has been shown to:
Improve endurance times( longer time to exhaustion)
Improve time-trial times (completed same amount of work using less energy)
Increase maximal oxygen uptake (VO2max) therefore improving overall performance
Female athletes most at risk of ID should be screened using Hgb and sFer.
Monitor Fe status, treatment, and counseling to ensure sufficient dietary intakes and prevent further decrements in Fe status with training.

11. References Journal Articles:

12. Questions??