Iron: The Secret Ingredient


Iron is a very important mineral essential in preventing anemia. Iron helps carry oxygen through our blood and into our muscles. Individuals with iron deficiency experience decreased performance, fatigue, poor recovery, and shortness of breath. Athletes have a higher risk for low iron levels because iron is lost through sweat and red blood cells are destroyed during the mechanical trauma of activities such as running.

There are two types of iron: heme and non-heme. Heme iron is located in animal products such as red meat and dark poultry. Non-heme iron is found in plant sources such as beans, spinach, and dried fruit. Heme iron is much easier for the body to absorb than non-heme iron.

Ferritin is an iron-containing blood cell protein and can be tested to see how much iron the body is storing. If ferritin levels are low, it indicates the body is low in iron. The normal range for ferritin is about 20-250 ng/mL.

My Story

Over the past year, my husband noticed my breathing was particularly heavy when I was running. I occasionally felt fatigued or had low energy, but I did not think anything of it. I knew running challenged me, and I always needed lots of rest. We were eating red meat once every 1-2 weeks and focused on a healthy diet overall. I never had my iron or ferritin levels tested, and this summer I decided it was time to get it done. My ferritin level came back as 18 ng/mL, which is very low.

Since the test, I have been taking an iron supplement almost every day and I increased my intake of heme iron particularly red meat to at least 1-2 times per week. It has been easy to make sure our meal plan has items such as hamburgers, pasta with meat sauce, stuffed peppers, steak fajitas, and turkey meatballs on a regular basis. I have also made an effort to continue to eat non-heme iron sources including beans, greens, and fortified foods.

Furthermore, iron absorption is enhanced by vitamin C and diminished by calcium. I have been focusing on consuming most of my calcium (dairy) in the AM, and then having foods high in vitamin C such as tomatoes and bell peppers in the PM when I consume most of my iron and when I take my supplement.

After three months of these changes, I can notice a significant improvement in my breathing and energy levels when running. I still need lots of sleep, but I definitely notice an extra pep in my step that has made a positive change in how I feel while training and has improved my quality of life.


Consumption of red meat is associated with several health problems including heart disease because it contains moderate amounts of saturated fat and cholesterol. For the general population, a diet containing mostly plant-based foods is ideal. However, for many people (including endurance athletes) having red meat 1-2 times per week is not a detriment to their health. I do try to buy grass-fed meat, serve appropriate portion sizes, and make sure the meat doesn’t act as a substitute for lots of vegetables and fruit and whole grains.

Everyone is different, and there are lots of runners and other individuals eating vegetarian diets without low iron. Some people even have high levels of iron. For me, it made the most sense to take a supplement and increase my iron intake through dietary changes. It will be important to continue to monitor my levels over the years to keep track and adjust as needed.


Ryan, Monique. Sports Nutrition for Endurance Athletes. 3rd ed., Velo, 2012.

Do you eat red meat? Have you ever had your iron level tested?