Updated: Mar 30
Are you experiencing prolonged fatigue, shortness of breath, or a sudden decrease in performance? If so, it may be a good idea to check your iron levels to see if your iron stores are low. In this article, we'll look at why iron is so crucial for runners, symptoms of low iron, sources of iron for both meat-eaters and vegetarians/vegans, and how to check your iron level.
Iron is an essential mineral that plays a vital role in the body's ability to produce energy. It is an integral component of hemoglobin, the protein in red blood cells that carries oxygen from the lungs to the muscles and tissues.
During exercise, the muscles use more oxygen, and if the body doesn't have enough iron to deliver oxygen to the muscles, it can lead to fatigue and reduced performance. Iron also produces collagen, essential for maintaining healthy connective tissue such as tendons and ligaments.
Iron deficiency, a condition in which the body doesn't have enough iron to produce enough red blood cells, can be a common problem for some runners, particularly for females, vegetarians, vegans, or with a history of gastrointestinal issues or heavy menstrual periods. These groups may be more at risk of developing iron deficiency due to their diet or other factors that can interfere with iron absorption.
Symptoms of Iron Deficiency
Symptoms of iron deficiency can vary, but some common symptoms in runners may include the following:
Fatigue: Iron deficiency can cause fatigue because the body does not have enough red blood cells to deliver oxygen to the muscles and tissues.
Decreased endurance: Iron deficiency can also lead to decreased endurance because the body does not have enough energy to sustain physical activity.
Shortness of breath: Iron deficiency can cause shortness of breath because the body does not have enough red blood cells to carry oxygen to the lungs.
Dizziness: Iron deficiency can cause dizziness because the brain lacks oxygen.
Pale skin: Iron deficiency can cause the skin to appear pale because there are not enough red blood cells to give it its normal color.
Cold hands and feet: Iron deficiency can cause the hands and feet to feel cold because there are not enough red blood cells to help regulate body temperature.
Heart palpitations: Iron deficiency can cause heart palpitations because the heart has to work harder to pump oxygen-poor blood.
Stages of Iron Deficiency
Alex Hutchinson writes iron deficiency can be divided into three stages:
Stage 1 is characterized by normal hemoglobin and transferrin saturation levels, but low ferritin levels (below 35 micrograms/L). At this stage, there may not be significant negative effects on performance, but it is a warning sign that iron deficiency could become a problem if not addressed.
In Stage 2, also known as iron-deficient non-anemia, hemoglobin levels remain normal (above 115 g/L), but transferrin saturation and ferritin levels are both low (below 16% and 20 micrograms/L, respectively). While some medical professionals may consider this stage without significant concern, sports scientists generally believe that improving iron levels can lead to improved performance.
Stage 3, or iron-deficient anemia, is marked by low levels of transferrin saturation, ferritin (below 12 micrograms/L), and hemoglobin (below 115 g/L). At this stage, it is important to correct iron deficiency as it can significantly negatively affect health and performance.
It's essential for runners to consume enough iron-rich foods and to pay attention to their iron levels, especially if they are experiencing symptoms of iron deficiency.
Good Sources Of Iron for Meat Eaters
Red meat: Beef, lamb, and pork are all high in iron. Three ounces of beef, for example, contains about 2.3 milligrams of iron.
Poultry: Chicken and turkey are good sources of iron. Three ounces of roasted chicken breast contains about 1 milligram of iron.
Fish: Fish, such as tuna, salmon, and sardines, is a good source of iron. Three ounces of canned tuna contains about 1 milligram of iron.
Organ meats: Organ meats, such as liver and kidney, are also high in iron. Three ounces of beef liver contain about 5.2 milligrams of iron.
It's important to note that the body absorbs iron from animal sources more easily than from plant sources. Therefore, people who follow a vegetarian or vegan diet may need to consume more iron-rich plant foods or take iron supplements to meet their needs.
Including vitamin C-rich foods with your iron-rich meals is also a good idea, as vitamin C can help increase iron absorption. Some examples of vitamin C-rich foods include oranges, strawberries, and bell peppers. Vegetarians and vegans may need to avoid consuming calcium-rich foods and drinks simultaneously with iron-rich foods, as calcium can interfere with iron absorption.
Good Sources Of Iron for Vegetarians and Vegans
Legumes: Beans, lentils, and chickpeas are all excellent sources of iron.
Tofu: Tofu is made from soybeans and is a good source of iron and protein.
Nuts and seeds: Pumpkin seeds, sunflower seeds, and almonds are all excellent sources of iron.
Grains: Quinoa, oats, and fortified cereals are all excellent sources of iron for vegetarians.
Dried fruit: Dried apricots, raisins, and prunes are all good sources of iron.
Leafy greens: Spinach, kale, and collard greens are all good sources of iron for vegetarians.
Fortified foods: Many plant-based milks and breakfast cereals are fortified with iron, making them a good source of the mineral for vegetarians.
How to Test for Low Iron
To test for low iron, a healthcare provider will typically order a blood test called a complete blood count (CBC). The CBC measures the levels of various components of the blood, including red blood cells, white blood cells, and platelets. It can also measure the amount of hemoglobin, a protein in red blood cells that carries oxygen from the lungs to the rest of the body, and the hematocrit, a measure of the volume of red blood cells in the blood.
Low hemoglobin and hematocrit levels can be a sign of iron deficiency anemia. If a CBC indicates that you have low iron levels, your healthcare provider may order additional tests to confirm the diagnosis and determine the cause of the deficiency. These tests may include a ferritin test, which measures the amount of iron stored in the body, or a serum iron test, which measures the amount of iron in the blood.
It's important to note that various factors, including poor nutrition, blood loss, and certain medical conditions, can cause low iron levels. Suppose you are experiencing symptoms of iron deficiency anemia or are concerned about your iron levels. In that case, it's a good idea to speak with a healthcare provider for guidance on optimizing your iron intake and addressing any underlying health issues.