The Importance of Iron for Performance

Iron is one of the most essential trace minerals for athletic performance and the general population. As a college athlete, your body demands extra nutrients, including iron. According to the Academy of Nutrition and Dietetics (AND) endurance athletes, especially long distance runners, have iron needs that are 70% higher than the general population. Iron is also one of the most common nutrient deficiencies seen in athletes, especially women.

Why is iron important?
Iron is essential for energy production, metabolism and to help carry oxygen to the cells. It is also essential for growth, development and the immune system to function normally.

Common causes of iron deficiency:

• Individuals on vegetarian or vegan diets. Iron is less available in plant-based products.
• Inadequate energy intake. 
• Iron loss in sweat, feces, urine, menstrual bleeding, GI bleed, foot-strike hemolysis (with every foot strike we break red blood cells), injury, and blood donation. 
• Medical disorder that prevents absorption of iron
• Pregnancy. More demands due to a growing fetus
• Growth spurt

Symptoms of iron deficiency:

• Fatigue, irritability, shortness of breath, dizziness, headache, coldness in your hands and feet, pale skin, chest pain and weakness. 

Consequences of iron deficiency: 

• Reduced endurance
• Muscle function weakens and ability to work is limited. 
• Can lead to iron deficiency anemia, which can take 3-6 months to reverse.

Possible benefits of improving iron deficiency: 

• Improved work volume and endurance. 
• Improved oxygen uptake. 
• Decreased lactate concentrations. 
• Decreased muscle fatigue. 

How to figure out of you are deficient:

A simple blood test allows to figure if you are deficient or not. The most common test is hemoglobin. However, low hemoglobin of < 12 g/dL for women and < 13.5 g/dL for men indicates iron deficiency anemia, which will require supplementation. You can be iron deficient with no anemia. In this case, it is highly recommended to test ferritin levels. Ferritin helps store iron in the body. If it is low, we have low iron stores as well. Although the normal lab values are 12-300 ng/dL in men and 12-150 ng/dL in women, it is found that ferritin below 35 ng/dL in athletes can affect performance and supplementation may be recommended. 

How to improve iron status:

Eat a balanced diet that meets your dietary needs. Women (19-50 years) need a minimum of 18 mg of iron each day and men 8 mg. Consult your doctor or health professional about taking an iron supplement if you do not feel that you can meet your iron needs by diet alone. 

Rich dietary sources of iron: 

• The most bio-available (best absorbed) sources of iron (also called heme iron): meat, poultry, and fish. 
• Other sources (plant derived sources are not absorbed as well. Called non-heme Iron): Ready-to-eat cereal, beans, tofu, nuts and dark leafy greens. 

Tips: 

• Choose breakfast cereals that are fortified with iron 
• Choose lean meat sources (e.g. Ground beef with less than 10% fat) 
• Consume iron rich foods with foods high in vitamin C to help your body absorb the iron better (e.g. Oranges, tomatoes, red peppers). 
• Avoid drinking tea with your iron containing meals. Substances in tea reduce the absorption of iron. 
• Avoid drinking milk with your iron containing meal.
• Oxalates and polyphenols are compounds found in certain fruits, herbs, nuts, chocolate and vegetables such as: spinach, kale, tea, beets, strawberries and rhubarb to name a few, that limit absorption of iron from non-heme sources. Cooking the vegetables may assist in preventing this from occuring.  

Guest Contributor: Emily Seidl, MS, RD