By Jenevieve Roper, MS (@JLynnFit)
It’s extremely important to ensure that your body always has the fuel it needs, which includes optimal levels of vitamins and minerals. These necessary health-enhancers play vital roles in your performance and energy levels, even though certain important ones are often overlooked. Iron, for example, never really seems to get the respect it deserves. You know you need it, but do you actually know your iron levels? Did you know that there are two different types of iron, or that you don’t have to be anemic to suffer the detrimental effects that an iron deficiency has on exercise performance? If you answered “no” to any of these questions, you just proved my point — it’s time to give iron its 15 minutes of fame.
What Is Iron?
Iron is a trace mineral and an essential nutrient, which women unfortunately store less of than men. This puts ladies at a higher risk for iron deficiency, so it’s important to understand how iron affects our bodies and why we need it.
One of the most important things to know is the difference between the two types of iron: heme and non-heme, as well as the different types of foods they come from. Heme iron is found in animal-based foods and is absorbed well by the body. The best natural food source is red meat, which means that vegetarians have to overcompensate in order to meet their body’s requirements, or they need to take supplements. Non-heme iron, on the other hand, is predominantly found in plant foods and is not as well absorbed by the body. However, this absorption rate can be improved when you consume foods filled with vitamin C or calcium at the same time as your non-meat-based iron sources.
Why We Need Iron
Iron has several different functions within our bodies. Among other things, this mighty mineral can single-handedly transport and receive oxygen, produce red blood cells, and affect both immune function and cognitive performance.
Our red blood cells contain a protein called hemoglobin, which has four iron atoms. Oxygen attaches to these atoms in the lungs before being transported throughout the body. Then there is a second iron- and oxygen-binding protein called myoglobin, which transports and stores oxygen from the blood within the muscles, meaning suboptimal iron absorption can have a significantly negative impact on both your oxygen transportation and storage.
In addition to its important role in spreading oxygen throughout the body, iron can also protect against highly reactive and unstable oxygen-containing molecules known as free radicals. They are produced during exercise and, should they come into contact with cell membranes, they can cause damage to both cells and DNA. DNA synthesis is a very precise process, so even small levels of damage can have significant, lasting effects.
Proper iron levels are also required for your immune system to function normally. Supplementing your body with either too much or too little iron can greatly change your immune status. If you’re iron deficient, you’ll have a suboptimal immune response when your body senses a virus or bacteria, which increases your risk of infection. That being said, if you consume too much, you can also increase your risk of infection because bacteria feeds on iron, meaning the more iron they can consume, the more likely they are to cause an infection. Clearly, balance is the key to success.
It may sound less than appetizing, but liver is hands down the best source of dietary iron. If you really can’t stomach it, try other organ delicacies like kidneys and hearts, or more common picks like seafood, lean meat, egg yolks, and poultry.
If the vegetarians among you are starting to panic, never fear! Dried beans, dried fruits, and vegetables are the best iron-filled plant sources, so include blueberries, spinach, potatoes (with their skins), and baked beans in your diet. If you know you’re on the shallow side of the iron pool, pass on corn, milk, and other dairy products. These picks have little to no iron content, meaning you’ll fill yourself up without snagging your dose of that much-needed mineral.
Are You At Risk For Iron Deficiency?
It may surprise you to learn that cross-country runners, those involved in endurance sports, women who suffer heavy menstrual losses, vegetarians, long-distance runners, or people who train in hot climates with heavy sweating face an increased risk of iron deficiency. If any of these sound like you, it is advised that you receive periodic screening to assess your iron status.
There are actually several reasons why athletes are particularly at risk. Sometimes during intense training, gastrointestinal (GI) bleeding can occur, and the more stressful the training, the greater the iron loss. Some GI diseases, like IBS and Crohn’s disease, can also interfere with absorption and cause an iron deficiency, particularly those that involve low-grade, chronic inflammation.
When it comes to an actual iron deficiency, there are three distinct stages. Stage one usually involves reduced or absent iron stores. Iron is typically stored in the liver and bone marrow, and measured by a blood test known as the ferritin test, which refers to an iron-storing protein inside your cells and indirectly measures the levels of iron in your blood. When someone reaches serum ferritin levels of 60 ng/dl or below, they are considered to be in this stage. Stage two usually occurs when there is a reduction of iron going to the red blood cells. This leads to a reduction in the oxygen-carrying capacity of the red blood cells, which can start to affect your abilities. Stage three results in a significant reduction of iron and hemoglobin to the red blood cells, which greatly affects athletic performance.
A fourth stage that is not a full-fledged iron deficiency is known as sports anemia and it occurs at the start of a training program. It causes a decrease in hemoglobin due to an increase in plasma volume, which is a result of endurance exercise. Strenuous training programs may also destroy red blood cells, or, if protein intake is also inadequate, the body’s need to form new muscle could conflict with creating more hemoglobin, which may cause anemia.
Recommended Daily Intake
So how much iron does a properly functioning body need to stay healthy? It has been reported that most female athletes only consume 1,600 to 2,000 calories per day, which typically provides about 12 mg of iron — compare that to the recommended intake for premenopausal women of 18 mg daily. Postmenopausal women have a lower recommendation of 8 mg per day, but that number jumps to 27 mg for those who are pregnant.
Taking the correct amount of iron is something everybody should be conscious of, but it’s particularly important for the female endurance athletes out there. Get your iron levels checked before and after you start a new training program so that you can supplement if necessary and use your iron intake to pump more iron, perform well, and create a healthier, happier you.